Age Owner Branch data TLA Line data Source code
1 : : /*-------------------------------------------------------------------------
2 : : *
3 : : * xlog.c
4 : : * PostgreSQL write-ahead log manager
5 : : *
6 : : * The Write-Ahead Log (WAL) functionality is split into several source
7 : : * files, in addition to this one:
8 : : *
9 : : * xloginsert.c - Functions for constructing WAL records
10 : : * xlogrecovery.c - WAL recovery and standby code
11 : : * xlogreader.c - Facility for reading WAL files and parsing WAL records
12 : : * xlogutils.c - Helper functions for WAL redo routines
13 : : *
14 : : * This file contains functions for coordinating database startup and
15 : : * checkpointing, and managing the write-ahead log buffers when the
16 : : * system is running.
17 : : *
18 : : * StartupXLOG() is the main entry point of the startup process. It
19 : : * coordinates database startup, performing WAL recovery, and the
20 : : * transition from WAL recovery into normal operations.
21 : : *
22 : : * XLogInsertRecord() inserts a WAL record into the WAL buffers. Most
23 : : * callers should not call this directly, but use the functions in
24 : : * xloginsert.c to construct the WAL record. XLogFlush() can be used
25 : : * to force the WAL to disk.
26 : : *
27 : : * In addition to those, there are many other functions for interrogating
28 : : * the current system state, and for starting/stopping backups.
29 : : *
30 : : *
31 : : * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group
32 : : * Portions Copyright (c) 1994, Regents of the University of California
33 : : *
34 : : * src/backend/access/transam/xlog.c
35 : : *
36 : : *-------------------------------------------------------------------------
37 : : */
38 : :
39 : : #include "postgres.h"
40 : :
41 : : #include <ctype.h>
42 : : #include <math.h>
43 : : #include <time.h>
44 : : #include <fcntl.h>
45 : : #include <sys/stat.h>
46 : : #include <sys/time.h>
47 : : #include <unistd.h>
48 : :
49 : : #include "access/clog.h"
50 : : #include "access/commit_ts.h"
51 : : #include "access/heaptoast.h"
52 : : #include "access/multixact.h"
53 : : #include "access/rewriteheap.h"
54 : : #include "access/subtrans.h"
55 : : #include "access/timeline.h"
56 : : #include "access/transam.h"
57 : : #include "access/twophase.h"
58 : : #include "access/xact.h"
59 : : #include "access/xlog_internal.h"
60 : : #include "access/xlogarchive.h"
61 : : #include "access/xloginsert.h"
62 : : #include "access/xlogreader.h"
63 : : #include "access/xlogrecovery.h"
64 : : #include "access/xlogutils.h"
65 : : #include "access/xlogwait.h"
66 : : #include "backup/basebackup.h"
67 : : #include "catalog/catversion.h"
68 : : #include "catalog/pg_control.h"
69 : : #include "catalog/pg_database.h"
70 : : #include "common/controldata_utils.h"
71 : : #include "common/file_utils.h"
72 : : #include "executor/instrument.h"
73 : : #include "miscadmin.h"
74 : : #include "pg_trace.h"
75 : : #include "pgstat.h"
76 : : #include "port/atomics.h"
77 : : #include "postmaster/bgwriter.h"
78 : : #include "postmaster/startup.h"
79 : : #include "postmaster/walsummarizer.h"
80 : : #include "postmaster/walwriter.h"
81 : : #include "replication/origin.h"
82 : : #include "replication/slot.h"
83 : : #include "replication/slotsync.h"
84 : : #include "replication/snapbuild.h"
85 : : #include "replication/walreceiver.h"
86 : : #include "replication/walsender.h"
87 : : #include "storage/bufmgr.h"
88 : : #include "storage/fd.h"
89 : : #include "storage/ipc.h"
90 : : #include "storage/large_object.h"
91 : : #include "storage/latch.h"
92 : : #include "storage/predicate.h"
93 : : #include "storage/proc.h"
94 : : #include "storage/procarray.h"
95 : : #include "storage/reinit.h"
96 : : #include "storage/spin.h"
97 : : #include "storage/sync.h"
98 : : #include "utils/guc_hooks.h"
99 : : #include "utils/guc_tables.h"
100 : : #include "utils/injection_point.h"
101 : : #include "utils/pgstat_internal.h"
102 : : #include "utils/ps_status.h"
103 : : #include "utils/relmapper.h"
104 : : #include "utils/snapmgr.h"
105 : : #include "utils/timeout.h"
106 : : #include "utils/timestamp.h"
107 : : #include "utils/varlena.h"
108 : : #include "utils/wait_event.h"
109 : :
110 : : #ifdef WAL_DEBUG
111 : : #include "utils/memutils.h"
112 : : #endif
113 : :
114 : : /* timeline ID to be used when bootstrapping */
115 : : #define BootstrapTimeLineID 1
116 : :
117 : : /* User-settable parameters */
118 : : int max_wal_size_mb = 1024; /* 1 GB */
119 : : int min_wal_size_mb = 80; /* 80 MB */
120 : : int wal_keep_size_mb = 0;
121 : : int XLOGbuffers = -1;
122 : : int XLogArchiveTimeout = 0;
123 : : int XLogArchiveMode = ARCHIVE_MODE_OFF;
124 : : char *XLogArchiveCommand = NULL;
125 : : bool EnableHotStandby = false;
126 : : bool fullPageWrites = true;
127 : : bool wal_log_hints = false;
128 : : int wal_compression = WAL_COMPRESSION_NONE;
129 : : char *wal_consistency_checking_string = NULL;
130 : : bool *wal_consistency_checking = NULL;
131 : : bool wal_init_zero = true;
132 : : bool wal_recycle = true;
133 : : bool log_checkpoints = true;
134 : : int wal_sync_method = DEFAULT_WAL_SYNC_METHOD;
135 : : int wal_level = WAL_LEVEL_REPLICA;
136 : : int CommitDelay = 0; /* precommit delay in microseconds */
137 : : int CommitSiblings = 5; /* # concurrent xacts needed to sleep */
138 : : int wal_retrieve_retry_interval = 5000;
139 : : int max_slot_wal_keep_size_mb = -1;
140 : : int wal_decode_buffer_size = 512 * 1024;
141 : : bool track_wal_io_timing = false;
142 : :
143 : : #ifdef WAL_DEBUG
144 : : bool XLOG_DEBUG = false;
145 : : #endif
146 : :
147 : : int wal_segment_size = DEFAULT_XLOG_SEG_SIZE;
148 : :
149 : : /*
150 : : * Number of WAL insertion locks to use. A higher value allows more insertions
151 : : * to happen concurrently, but adds some CPU overhead to flushing the WAL,
152 : : * which needs to iterate all the locks.
153 : : */
154 : : #define NUM_XLOGINSERT_LOCKS 8
155 : :
156 : : /*
157 : : * Max distance from last checkpoint, before triggering a new xlog-based
158 : : * checkpoint.
159 : : */
160 : : int CheckPointSegments;
161 : :
162 : : /* Estimated distance between checkpoints, in bytes */
163 : : static double CheckPointDistanceEstimate = 0;
164 : : static double PrevCheckPointDistance = 0;
165 : :
166 : : /*
167 : : * Track whether there were any deferred checks for custom resource managers
168 : : * specified in wal_consistency_checking.
169 : : */
170 : : static bool check_wal_consistency_checking_deferred = false;
171 : :
172 : : /*
173 : : * GUC support
174 : : */
175 : : const struct config_enum_entry wal_sync_method_options[] = {
176 : : {"fsync", WAL_SYNC_METHOD_FSYNC, false},
177 : : #ifdef HAVE_FSYNC_WRITETHROUGH
178 : : {"fsync_writethrough", WAL_SYNC_METHOD_FSYNC_WRITETHROUGH, false},
179 : : #endif
180 : : {"fdatasync", WAL_SYNC_METHOD_FDATASYNC, false},
181 : : #ifdef O_SYNC
182 : : {"open_sync", WAL_SYNC_METHOD_OPEN, false},
183 : : #endif
184 : : #ifdef O_DSYNC
185 : : {"open_datasync", WAL_SYNC_METHOD_OPEN_DSYNC, false},
186 : : #endif
187 : : {NULL, 0, false}
188 : : };
189 : :
190 : :
191 : : /*
192 : : * Although only "on", "off", and "always" are documented,
193 : : * we accept all the likely variants of "on" and "off".
194 : : */
195 : : const struct config_enum_entry archive_mode_options[] = {
196 : : {"always", ARCHIVE_MODE_ALWAYS, false},
197 : : {"on", ARCHIVE_MODE_ON, false},
198 : : {"off", ARCHIVE_MODE_OFF, false},
199 : : {"true", ARCHIVE_MODE_ON, true},
200 : : {"false", ARCHIVE_MODE_OFF, true},
201 : : {"yes", ARCHIVE_MODE_ON, true},
202 : : {"no", ARCHIVE_MODE_OFF, true},
203 : : {"1", ARCHIVE_MODE_ON, true},
204 : : {"0", ARCHIVE_MODE_OFF, true},
205 : : {NULL, 0, false}
206 : : };
207 : :
208 : : /*
209 : : * Statistics for current checkpoint are collected in this global struct.
210 : : * Because only the checkpointer or a stand-alone backend can perform
211 : : * checkpoints, this will be unused in normal backends.
212 : : */
213 : : CheckpointStatsData CheckpointStats;
214 : :
215 : : /*
216 : : * During recovery, lastFullPageWrites keeps track of full_page_writes that
217 : : * the replayed WAL records indicate. It's initialized with full_page_writes
218 : : * that the recovery starting checkpoint record indicates, and then updated
219 : : * each time XLOG_FPW_CHANGE record is replayed.
220 : : */
221 : : static bool lastFullPageWrites;
222 : :
223 : : /*
224 : : * Local copy of the state tracked by SharedRecoveryState in shared memory,
225 : : * It is false if SharedRecoveryState is RECOVERY_STATE_DONE. True actually
226 : : * means "not known, need to check the shared state".
227 : : */
228 : : static bool LocalRecoveryInProgress = true;
229 : :
230 : : /*
231 : : * Local state for XLogInsertAllowed():
232 : : * 1: unconditionally allowed to insert XLOG
233 : : * 0: unconditionally not allowed to insert XLOG
234 : : * -1: must check RecoveryInProgress(); disallow until it is false
235 : : * Most processes start with -1 and transition to 1 after seeing that recovery
236 : : * is not in progress. But we can also force the value for special cases.
237 : : * The coding in XLogInsertAllowed() depends on the first two of these states
238 : : * being numerically the same as bool true and false.
239 : : */
240 : : static int LocalXLogInsertAllowed = -1;
241 : :
242 : : /*
243 : : * ProcLastRecPtr points to the start of the last XLOG record inserted by the
244 : : * current backend. It is updated for all inserts. XactLastRecEnd points to
245 : : * end+1 of the last record, and is reset when we end a top-level transaction,
246 : : * or start a new one; so it can be used to tell if the current transaction has
247 : : * created any XLOG records.
248 : : *
249 : : * While in parallel mode, this may not be fully up to date. When committing,
250 : : * a transaction can assume this covers all xlog records written either by the
251 : : * user backend or by any parallel worker which was present at any point during
252 : : * the transaction. But when aborting, or when still in parallel mode, other
253 : : * parallel backends may have written WAL records at later LSNs than the value
254 : : * stored here. The parallel leader advances its own copy, when necessary,
255 : : * in WaitForParallelWorkersToFinish.
256 : : */
257 : : XLogRecPtr ProcLastRecPtr = InvalidXLogRecPtr;
258 : : XLogRecPtr XactLastRecEnd = InvalidXLogRecPtr;
259 : : XLogRecPtr XactLastCommitEnd = InvalidXLogRecPtr;
260 : :
261 : : /*
262 : : * RedoRecPtr is this backend's local copy of the REDO record pointer
263 : : * (which is almost but not quite the same as a pointer to the most recent
264 : : * CHECKPOINT record). We update this from the shared-memory copy,
265 : : * XLogCtl->Insert.RedoRecPtr, whenever we can safely do so (ie, when we
266 : : * hold an insertion lock). See XLogInsertRecord for details. We are also
267 : : * allowed to update from XLogCtl->RedoRecPtr if we hold the info_lck;
268 : : * see GetRedoRecPtr.
269 : : *
270 : : * NB: Code that uses this variable must be prepared not only for the
271 : : * possibility that it may be arbitrarily out of date, but also for the
272 : : * possibility that it might be set to InvalidXLogRecPtr. We used to
273 : : * initialize it as a side effect of the first call to RecoveryInProgress(),
274 : : * which meant that most code that might use it could assume that it had a
275 : : * real if perhaps stale value. That's no longer the case.
276 : : */
277 : : static XLogRecPtr RedoRecPtr;
278 : :
279 : : /*
280 : : * doPageWrites is this backend's local copy of (fullPageWrites ||
281 : : * runningBackups > 0). It is used together with RedoRecPtr to decide whether
282 : : * a full-page image of a page need to be taken.
283 : : *
284 : : * NB: Initially this is false, and there's no guarantee that it will be
285 : : * initialized to any other value before it is first used. Any code that
286 : : * makes use of it must recheck the value after obtaining a WALInsertLock,
287 : : * and respond appropriately if it turns out that the previous value wasn't
288 : : * accurate.
289 : : */
290 : : static bool doPageWrites;
291 : :
292 : : /*----------
293 : : * Shared-memory data structures for XLOG control
294 : : *
295 : : * LogwrtRqst indicates a byte position that we need to write and/or fsync
296 : : * the log up to (all records before that point must be written or fsynced).
297 : : * The positions already written/fsynced are maintained in logWriteResult
298 : : * and logFlushResult using atomic access.
299 : : * In addition to the shared variable, each backend has a private copy of
300 : : * both in LogwrtResult, which is updated when convenient.
301 : : *
302 : : * The request bookkeeping is simpler: there is a shared XLogCtl->LogwrtRqst
303 : : * (protected by info_lck), but we don't need to cache any copies of it.
304 : : *
305 : : * info_lck is only held long enough to read/update the protected variables,
306 : : * so it's a plain spinlock. The other locks are held longer (potentially
307 : : * over I/O operations), so we use LWLocks for them. These locks are:
308 : : *
309 : : * WALBufMappingLock: must be held to replace a page in the WAL buffer cache.
310 : : * It is only held while initializing and changing the mapping. If the
311 : : * contents of the buffer being replaced haven't been written yet, the mapping
312 : : * lock is released while the write is done, and reacquired afterwards.
313 : : *
314 : : * WALWriteLock: must be held to write WAL buffers to disk (XLogWrite or
315 : : * XLogFlush).
316 : : *
317 : : * ControlFileLock: must be held to read/update control file or create
318 : : * new log file.
319 : : *
320 : : *----------
321 : : */
322 : :
323 : : typedef struct XLogwrtRqst
324 : : {
325 : : XLogRecPtr Write; /* last byte + 1 to write out */
326 : : XLogRecPtr Flush; /* last byte + 1 to flush */
327 : : } XLogwrtRqst;
328 : :
329 : : typedef struct XLogwrtResult
330 : : {
331 : : XLogRecPtr Write; /* last byte + 1 written out */
332 : : XLogRecPtr Flush; /* last byte + 1 flushed */
333 : : } XLogwrtResult;
334 : :
335 : : /*
336 : : * Inserting to WAL is protected by a small fixed number of WAL insertion
337 : : * locks. To insert to the WAL, you must hold one of the locks - it doesn't
338 : : * matter which one. To lock out other concurrent insertions, you must hold
339 : : * of them. Each WAL insertion lock consists of a lightweight lock, plus an
340 : : * indicator of how far the insertion has progressed (insertingAt).
341 : : *
342 : : * The insertingAt values are read when a process wants to flush WAL from
343 : : * the in-memory buffers to disk, to check that all the insertions to the
344 : : * region the process is about to write out have finished. You could simply
345 : : * wait for all currently in-progress insertions to finish, but the
346 : : * insertingAt indicator allows you to ignore insertions to later in the WAL,
347 : : * so that you only wait for the insertions that are modifying the buffers
348 : : * you're about to write out.
349 : : *
350 : : * This isn't just an optimization. If all the WAL buffers are dirty, an
351 : : * inserter that's holding a WAL insert lock might need to evict an old WAL
352 : : * buffer, which requires flushing the WAL. If it's possible for an inserter
353 : : * to block on another inserter unnecessarily, deadlock can arise when two
354 : : * inserters holding a WAL insert lock wait for each other to finish their
355 : : * insertion.
356 : : *
357 : : * Small WAL records that don't cross a page boundary never update the value,
358 : : * the WAL record is just copied to the page and the lock is released. But
359 : : * to avoid the deadlock-scenario explained above, the indicator is always
360 : : * updated before sleeping while holding an insertion lock.
361 : : *
362 : : * lastImportantAt contains the LSN of the last important WAL record inserted
363 : : * using a given lock. This value is used to detect if there has been
364 : : * important WAL activity since the last time some action, like a checkpoint,
365 : : * was performed - allowing to not repeat the action if not. The LSN is
366 : : * updated for all insertions, unless the XLOG_MARK_UNIMPORTANT flag was
367 : : * set. lastImportantAt is never cleared, only overwritten by the LSN of newer
368 : : * records. Tracking the WAL activity directly in WALInsertLock has the
369 : : * advantage of not needing any additional locks to update the value.
370 : : */
371 : : typedef struct
372 : : {
373 : : LWLock lock;
374 : : pg_atomic_uint64 insertingAt;
375 : : XLogRecPtr lastImportantAt;
376 : : } WALInsertLock;
377 : :
378 : : /*
379 : : * All the WAL insertion locks are allocated as an array in shared memory. We
380 : : * force the array stride to be a power of 2, which saves a few cycles in
381 : : * indexing, but more importantly also ensures that individual slots don't
382 : : * cross cache line boundaries. (Of course, we have to also ensure that the
383 : : * array start address is suitably aligned.)
384 : : */
385 : : typedef union WALInsertLockPadded
386 : : {
387 : : WALInsertLock l;
388 : : char pad[PG_CACHE_LINE_SIZE];
389 : : } WALInsertLockPadded;
390 : :
391 : : /*
392 : : * Session status of running backup, used for sanity checks in SQL-callable
393 : : * functions to start and stop backups.
394 : : */
395 : : static SessionBackupState sessionBackupState = SESSION_BACKUP_NONE;
396 : :
397 : : /*
398 : : * Shared state data for WAL insertion.
399 : : */
400 : : typedef struct XLogCtlInsert
401 : : {
402 : : slock_t insertpos_lck; /* protects CurrBytePos and PrevBytePos */
403 : :
404 : : /*
405 : : * CurrBytePos is the end of reserved WAL. The next record will be
406 : : * inserted at that position. PrevBytePos is the start position of the
407 : : * previously inserted (or rather, reserved) record - it is copied to the
408 : : * prev-link of the next record. These are stored as "usable byte
409 : : * positions" rather than XLogRecPtrs (see XLogBytePosToRecPtr()).
410 : : */
411 : : uint64 CurrBytePos;
412 : : uint64 PrevBytePos;
413 : :
414 : : /*
415 : : * Make sure the above heavily-contended spinlock and byte positions are
416 : : * on their own cache line. In particular, the RedoRecPtr and full page
417 : : * write variables below should be on a different cache line. They are
418 : : * read on every WAL insertion, but updated rarely, and we don't want
419 : : * those reads to steal the cache line containing Curr/PrevBytePos.
420 : : */
421 : : char pad[PG_CACHE_LINE_SIZE];
422 : :
423 : : /*
424 : : * fullPageWrites is the authoritative value used by all backends to
425 : : * determine whether to write full-page image to WAL. This shared value,
426 : : * instead of the process-local fullPageWrites, is required because, when
427 : : * full_page_writes is changed by SIGHUP, we must WAL-log it before it
428 : : * actually affects WAL-logging by backends. Checkpointer sets at startup
429 : : * or after SIGHUP.
430 : : *
431 : : * To read these fields, you must hold an insertion lock. To modify them,
432 : : * you must hold ALL the locks.
433 : : */
434 : : XLogRecPtr RedoRecPtr; /* current redo point for insertions */
435 : : bool fullPageWrites;
436 : :
437 : : /*
438 : : * runningBackups is a counter indicating the number of backups currently
439 : : * in progress. lastBackupStart is the latest checkpoint redo location
440 : : * used as a starting point for an online backup.
441 : : */
442 : : int runningBackups;
443 : : XLogRecPtr lastBackupStart;
444 : :
445 : : /*
446 : : * WAL insertion locks.
447 : : */
448 : : WALInsertLockPadded *WALInsertLocks;
449 : : } XLogCtlInsert;
450 : :
451 : : /*
452 : : * Total shared-memory state for XLOG.
453 : : */
454 : : typedef struct XLogCtlData
455 : : {
456 : : XLogCtlInsert Insert;
457 : :
458 : : /* Protected by info_lck: */
459 : : XLogwrtRqst LogwrtRqst;
460 : : XLogRecPtr RedoRecPtr; /* a recent copy of Insert->RedoRecPtr */
461 : : XLogRecPtr asyncXactLSN; /* LSN of newest async commit/abort */
462 : : XLogRecPtr replicationSlotMinLSN; /* oldest LSN needed by any slot */
463 : :
464 : : XLogSegNo lastRemovedSegNo; /* latest removed/recycled XLOG segment */
465 : :
466 : : /* Fake LSN counter, for unlogged relations. */
467 : : pg_atomic_uint64 unloggedLSN;
468 : :
469 : : /* Time and LSN of last xlog segment switch. Protected by WALWriteLock. */
470 : : pg_time_t lastSegSwitchTime;
471 : : XLogRecPtr lastSegSwitchLSN;
472 : :
473 : : /* These are accessed using atomics -- info_lck not needed */
474 : : pg_atomic_uint64 logInsertResult; /* last byte + 1 inserted to buffers */
475 : : pg_atomic_uint64 logWriteResult; /* last byte + 1 written out */
476 : : pg_atomic_uint64 logFlushResult; /* last byte + 1 flushed */
477 : :
478 : : /*
479 : : * Latest initialized page in the cache (last byte position + 1).
480 : : *
481 : : * To change the identity of a buffer (and InitializedUpTo), you need to
482 : : * hold WALBufMappingLock. To change the identity of a buffer that's
483 : : * still dirty, the old page needs to be written out first, and for that
484 : : * you need WALWriteLock, and you need to ensure that there are no
485 : : * in-progress insertions to the page by calling
486 : : * WaitXLogInsertionsToFinish().
487 : : */
488 : : XLogRecPtr InitializedUpTo;
489 : :
490 : : /*
491 : : * These values do not change after startup, although the pointed-to pages
492 : : * and xlblocks values certainly do. xlblocks values are protected by
493 : : * WALBufMappingLock.
494 : : */
495 : : char *pages; /* buffers for unwritten XLOG pages */
496 : : pg_atomic_uint64 *xlblocks; /* 1st byte ptr-s + XLOG_BLCKSZ */
497 : : int XLogCacheBlck; /* highest allocated xlog buffer index */
498 : :
499 : : /*
500 : : * InsertTimeLineID is the timeline into which new WAL is being inserted
501 : : * and flushed. It is zero during recovery, and does not change once set.
502 : : *
503 : : * If we create a new timeline when the system was started up,
504 : : * PrevTimeLineID is the old timeline's ID that we forked off from.
505 : : * Otherwise it's equal to InsertTimeLineID.
506 : : *
507 : : * We set these fields while holding info_lck. Most that reads these
508 : : * values knows that recovery is no longer in progress and so can safely
509 : : * read the value without a lock, but code that could be run either during
510 : : * or after recovery can take info_lck while reading these values.
511 : : */
512 : : TimeLineID InsertTimeLineID;
513 : : TimeLineID PrevTimeLineID;
514 : :
515 : : /*
516 : : * SharedRecoveryState indicates if we're still in crash or archive
517 : : * recovery. Protected by info_lck.
518 : : */
519 : : RecoveryState SharedRecoveryState;
520 : :
521 : : /*
522 : : * InstallXLogFileSegmentActive indicates whether the checkpointer should
523 : : * arrange for future segments by recycling and/or PreallocXlogFiles().
524 : : * Protected by ControlFileLock. Only the startup process changes it. If
525 : : * true, anyone can use InstallXLogFileSegment(). If false, the startup
526 : : * process owns the exclusive right to install segments, by reading from
527 : : * the archive and possibly replacing existing files.
528 : : */
529 : : bool InstallXLogFileSegmentActive;
530 : :
531 : : /*
532 : : * WalWriterSleeping indicates whether the WAL writer is currently in
533 : : * low-power mode (and hence should be nudged if an async commit occurs).
534 : : * Protected by info_lck.
535 : : */
536 : : bool WalWriterSleeping;
537 : :
538 : : /*
539 : : * During recovery, we keep a copy of the latest checkpoint record here.
540 : : * lastCheckPointRecPtr points to start of checkpoint record and
541 : : * lastCheckPointEndPtr points to end+1 of checkpoint record. Used by the
542 : : * checkpointer when it wants to create a restartpoint.
543 : : *
544 : : * Protected by info_lck.
545 : : */
546 : : XLogRecPtr lastCheckPointRecPtr;
547 : : XLogRecPtr lastCheckPointEndPtr;
548 : : CheckPoint lastCheckPoint;
549 : :
550 : : /*
551 : : * lastFpwDisableRecPtr points to the start of the last replayed
552 : : * XLOG_FPW_CHANGE record that instructs full_page_writes is disabled.
553 : : */
554 : : XLogRecPtr lastFpwDisableRecPtr;
555 : :
556 : : slock_t info_lck; /* locks shared variables shown above */
557 : : } XLogCtlData;
558 : :
559 : : /*
560 : : * Classification of XLogInsertRecord operations.
561 : : */
562 : : typedef enum
563 : : {
564 : : WALINSERT_NORMAL,
565 : : WALINSERT_SPECIAL_SWITCH,
566 : : WALINSERT_SPECIAL_CHECKPOINT
567 : : } WalInsertClass;
568 : :
569 : : static XLogCtlData *XLogCtl = NULL;
570 : :
571 : : /* a private copy of XLogCtl->Insert.WALInsertLocks, for convenience */
572 : : static WALInsertLockPadded *WALInsertLocks = NULL;
573 : :
574 : : /*
575 : : * We maintain an image of pg_control in shared memory.
576 : : */
577 : : static ControlFileData *ControlFile = NULL;
578 : :
579 : : /*
580 : : * Calculate the amount of space left on the page after 'endptr'. Beware
581 : : * multiple evaluation!
582 : : */
583 : : #define INSERT_FREESPACE(endptr) \
584 : : (((endptr) % XLOG_BLCKSZ == 0) ? 0 : (XLOG_BLCKSZ - (endptr) % XLOG_BLCKSZ))
585 : :
586 : : /* Macro to advance to next buffer index. */
587 : : #define NextBufIdx(idx) \
588 : : (((idx) == XLogCtl->XLogCacheBlck) ? 0 : ((idx) + 1))
589 : :
590 : : /*
591 : : * XLogRecPtrToBufIdx returns the index of the WAL buffer that holds, or
592 : : * would hold if it was in cache, the page containing 'recptr'.
593 : : */
594 : : #define XLogRecPtrToBufIdx(recptr) \
595 : : (((recptr) / XLOG_BLCKSZ) % (XLogCtl->XLogCacheBlck + 1))
596 : :
597 : : /*
598 : : * These are the number of bytes in a WAL page usable for WAL data.
599 : : */
600 : : #define UsableBytesInPage (XLOG_BLCKSZ - SizeOfXLogShortPHD)
601 : :
602 : : /*
603 : : * Convert values of GUCs measured in megabytes to equiv. segment count.
604 : : * Rounds down.
605 : : */
606 : : #define ConvertToXSegs(x, segsize) XLogMBVarToSegs((x), (segsize))
607 : :
608 : : /* The number of bytes in a WAL segment usable for WAL data. */
609 : : static int UsableBytesInSegment;
610 : :
611 : : /*
612 : : * Private, possibly out-of-date copy of shared LogwrtResult.
613 : : * See discussion above.
614 : : */
615 : : static XLogwrtResult LogwrtResult = {0, 0};
616 : :
617 : : /*
618 : : * Update local copy of shared XLogCtl->log{Write,Flush}Result
619 : : *
620 : : * It's critical that Flush always trails Write, so the order of the reads is
621 : : * important, as is the barrier. See also XLogWrite.
622 : : */
623 : : #define RefreshXLogWriteResult(_target) \
624 : : do { \
625 : : _target.Flush = pg_atomic_read_u64(&XLogCtl->logFlushResult); \
626 : : pg_read_barrier(); \
627 : : _target.Write = pg_atomic_read_u64(&XLogCtl->logWriteResult); \
628 : : } while (0)
629 : :
630 : : /*
631 : : * openLogFile is -1 or a kernel FD for an open log file segment.
632 : : * openLogSegNo identifies the segment, and openLogTLI the corresponding TLI.
633 : : * These variables are only used to write the XLOG, and so will normally refer
634 : : * to the active segment.
635 : : *
636 : : * Note: call Reserve/ReleaseExternalFD to track consumption of this FD.
637 : : */
638 : : static int openLogFile = -1;
639 : : static XLogSegNo openLogSegNo = 0;
640 : : static TimeLineID openLogTLI = 0;
641 : :
642 : : /*
643 : : * Local copies of equivalent fields in the control file. When running
644 : : * crash recovery, LocalMinRecoveryPoint is set to InvalidXLogRecPtr as we
645 : : * expect to replay all the WAL available, and updateMinRecoveryPoint is
646 : : * switched to false to prevent any updates while replaying records.
647 : : * Those values are kept consistent as long as crash recovery runs.
648 : : */
649 : : static XLogRecPtr LocalMinRecoveryPoint;
650 : : static TimeLineID LocalMinRecoveryPointTLI;
651 : : static bool updateMinRecoveryPoint = true;
652 : :
653 : : /* For WALInsertLockAcquire/Release functions */
654 : : static int MyLockNo = 0;
655 : : static bool holdingAllLocks = false;
656 : :
657 : : #ifdef WAL_DEBUG
658 : : static MemoryContext walDebugCxt = NULL;
659 : : #endif
660 : :
661 : : static void CleanupAfterArchiveRecovery(TimeLineID EndOfLogTLI,
662 : : XLogRecPtr EndOfLog,
663 : : TimeLineID newTLI);
664 : : static void CheckRequiredParameterValues(void);
665 : : static void XLogReportParameters(void);
666 : : static int LocalSetXLogInsertAllowed(void);
667 : : static void CreateEndOfRecoveryRecord(void);
668 : : static XLogRecPtr CreateOverwriteContrecordRecord(XLogRecPtr aborted_lsn,
669 : : XLogRecPtr pagePtr,
670 : : TimeLineID newTLI);
671 : : static void CheckPointGuts(XLogRecPtr checkPointRedo, int flags);
672 : : static void KeepLogSeg(XLogRecPtr recptr, XLogSegNo *logSegNo);
673 : :
674 : : static void AdvanceXLInsertBuffer(XLogRecPtr upto, TimeLineID tli,
675 : : bool opportunistic);
676 : : static void XLogWrite(XLogwrtRqst WriteRqst, TimeLineID tli, bool flexible);
677 : : static bool InstallXLogFileSegment(XLogSegNo *segno, char *tmppath,
678 : : bool find_free, XLogSegNo max_segno,
679 : : TimeLineID tli);
680 : : static void XLogFileClose(void);
681 : : static void PreallocXlogFiles(XLogRecPtr endptr, TimeLineID tli);
682 : : static void RemoveTempXlogFiles(void);
683 : : static void RemoveOldXlogFiles(XLogSegNo segno, XLogRecPtr lastredoptr,
684 : : XLogRecPtr endptr, TimeLineID insertTLI);
685 : : static void RemoveXlogFile(const struct dirent *segment_de,
686 : : XLogSegNo recycleSegNo, XLogSegNo *endlogSegNo,
687 : : TimeLineID insertTLI);
688 : : static void UpdateLastRemovedPtr(char *filename);
689 : : static void ValidateXLOGDirectoryStructure(void);
690 : : static void CleanupBackupHistory(void);
691 : : static void UpdateMinRecoveryPoint(XLogRecPtr lsn, bool force);
692 : : static bool PerformRecoveryXLogAction(void);
693 : : static void InitControlFile(uint64 sysidentifier, uint32 data_checksum_version);
694 : : static void WriteControlFile(void);
695 : : static void ReadControlFile(void);
696 : : static void UpdateControlFile(void);
697 : : static char *str_time(pg_time_t tnow, char *buf, size_t bufsize);
698 : :
699 : : static int get_sync_bit(int method);
700 : :
701 : : static void CopyXLogRecordToWAL(int write_len, bool isLogSwitch,
702 : : XLogRecData *rdata,
703 : : XLogRecPtr StartPos, XLogRecPtr EndPos,
704 : : TimeLineID tli);
705 : : static void ReserveXLogInsertLocation(int size, XLogRecPtr *StartPos,
706 : : XLogRecPtr *EndPos, XLogRecPtr *PrevPtr);
707 : : static bool ReserveXLogSwitch(XLogRecPtr *StartPos, XLogRecPtr *EndPos,
708 : : XLogRecPtr *PrevPtr);
709 : : static XLogRecPtr WaitXLogInsertionsToFinish(XLogRecPtr upto);
710 : : static char *GetXLogBuffer(XLogRecPtr ptr, TimeLineID tli);
711 : : static XLogRecPtr XLogBytePosToRecPtr(uint64 bytepos);
712 : : static XLogRecPtr XLogBytePosToEndRecPtr(uint64 bytepos);
713 : : static uint64 XLogRecPtrToBytePos(XLogRecPtr ptr);
714 : :
715 : : static void WALInsertLockAcquire(void);
716 : : static void WALInsertLockAcquireExclusive(void);
717 : : static void WALInsertLockRelease(void);
718 : : static void WALInsertLockUpdateInsertingAt(XLogRecPtr insertingAt);
719 : :
720 : : /*
721 : : * Insert an XLOG record represented by an already-constructed chain of data
722 : : * chunks. This is a low-level routine; to construct the WAL record header
723 : : * and data, use the higher-level routines in xloginsert.c.
724 : : *
725 : : * If 'fpw_lsn' is valid, it is the oldest LSN among the pages that this
726 : : * WAL record applies to, that were not included in the record as full page
727 : : * images. If fpw_lsn <= RedoRecPtr, the function does not perform the
728 : : * insertion and returns InvalidXLogRecPtr. The caller can then recalculate
729 : : * which pages need a full-page image, and retry. If fpw_lsn is invalid, the
730 : : * record is always inserted.
731 : : *
732 : : * 'flags' gives more in-depth control on the record being inserted. See
733 : : * XLogSetRecordFlags() for details.
734 : : *
735 : : * 'topxid_included' tells whether the top-transaction id is logged along with
736 : : * current subtransaction. See XLogRecordAssemble().
737 : : *
738 : : * The first XLogRecData in the chain must be for the record header, and its
739 : : * data must be MAXALIGNed. XLogInsertRecord fills in the xl_prev and
740 : : * xl_crc fields in the header, the rest of the header must already be filled
741 : : * by the caller.
742 : : *
743 : : * Returns XLOG pointer to end of record (beginning of next record).
744 : : * This can be used as LSN for data pages affected by the logged action.
745 : : * (LSN is the XLOG point up to which the XLOG must be flushed to disk
746 : : * before the data page can be written out. This implements the basic
747 : : * WAL rule "write the log before the data".)
748 : : */
749 : : XLogRecPtr
3370 andres@anarazel.de 750 :CBC 16071080 : XLogInsertRecord(XLogRecData *rdata,
751 : : XLogRecPtr fpw_lsn,
752 : : uint8 flags,
753 : : int num_fpi,
754 : : uint64 fpi_bytes,
755 : : bool topxid_included)
756 : : {
9124 bruce@momjian.us 757 : 16071080 : XLogCtlInsert *Insert = &XLogCtl->Insert;
758 : : pg_crc32c rdata_crc;
759 : : bool inserted;
4147 heikki.linnakangas@i 760 : 16071080 : XLogRecord *rechdr = (XLogRecord *) rdata->data;
3418 tgl@sss.pgh.pa.us 761 : 16071080 : uint8 info = rechdr->xl_info & ~XLR_INFO_MASK;
878 rhaas@postgresql.org 762 : 16071080 : WalInsertClass class = WALINSERT_NORMAL;
763 : : XLogRecPtr StartPos;
764 : : XLogRecPtr EndPos;
2740 akapila@postgresql.o 765 : 16071080 : bool prevDoPageWrites = doPageWrites;
766 : : TimeLineID insertTLI;
767 : :
768 : : /* Does this record type require special handling? */
878 rhaas@postgresql.org 769 [ + + ]: 16071080 : if (unlikely(rechdr->xl_rmid == RM_XLOG_ID))
770 : : {
771 [ + + ]: 238303 : if (info == XLOG_SWITCH)
772 : 816 : class = WALINSERT_SPECIAL_SWITCH;
773 [ + + ]: 237487 : else if (info == XLOG_CHECKPOINT_REDO)
774 : 933 : class = WALINSERT_SPECIAL_CHECKPOINT;
775 : : }
776 : :
777 : : /* we assume that all of the record header is in the first chunk */
4133 heikki.linnakangas@i 778 [ - + ]: 16071080 : Assert(rdata->len >= SizeOfXLogRecord);
779 : :
780 : : /* cross-check on whether we should be here or not */
6106 tgl@sss.pgh.pa.us 781 [ - + ]: 16071080 : if (!XLogInsertAllowed())
6106 tgl@sss.pgh.pa.us 782 [ # # ]:UBC 0 : elog(ERROR, "cannot make new WAL entries during recovery");
783 : :
784 : : /*
785 : : * Given that we're not in recovery, InsertTimeLineID is set and can't
786 : : * change, so we can read it without a lock.
787 : : */
1586 rhaas@postgresql.org 788 :CBC 16071080 : insertTLI = XLogCtl->InsertTimeLineID;
789 : :
790 : : /*----------
791 : : *
792 : : * We have now done all the preparatory work we can without holding a
793 : : * lock or modifying shared state. From here on, inserting the new WAL
794 : : * record to the shared WAL buffer cache is a two-step process:
795 : : *
796 : : * 1. Reserve the right amount of space from the WAL. The current head of
797 : : * reserved space is kept in Insert->CurrBytePos, and is protected by
798 : : * insertpos_lck.
799 : : *
800 : : * 2. Copy the record to the reserved WAL space. This involves finding the
801 : : * correct WAL buffer containing the reserved space, and copying the
802 : : * record in place. This can be done concurrently in multiple processes.
803 : : *
804 : : * To keep track of which insertions are still in-progress, each concurrent
805 : : * inserter acquires an insertion lock. In addition to just indicating that
806 : : * an insertion is in progress, the lock tells others how far the inserter
807 : : * has progressed. There is a small fixed number of insertion locks,
808 : : * determined by NUM_XLOGINSERT_LOCKS. When an inserter crosses a page
809 : : * boundary, it updates the value stored in the lock to the how far it has
810 : : * inserted, to allow the previous buffer to be flushed.
811 : : *
812 : : * Holding onto an insertion lock also protects RedoRecPtr and
813 : : * fullPageWrites from changing until the insertion is finished.
814 : : *
815 : : * Step 2 can usually be done completely in parallel. If the required WAL
816 : : * page is not initialized yet, you have to grab WALBufMappingLock to
817 : : * initialize it, but the WAL writer tries to do that ahead of insertions
818 : : * to avoid that from happening in the critical path.
819 : : *
820 : : *----------
821 : : */
5177 heikki.linnakangas@i 822 : 16071080 : START_CRIT_SECTION();
823 : :
878 rhaas@postgresql.org 824 [ + + ]: 16071080 : if (likely(class == WALINSERT_NORMAL))
825 : : {
887 826 : 16069331 : WALInsertLockAcquire();
827 : :
828 : : /*
829 : : * Check to see if my copy of RedoRecPtr is out of date. If so, may
830 : : * have to go back and have the caller recompute everything. This can
831 : : * only happen just after a checkpoint, so it's better to be slow in
832 : : * this case and fast otherwise.
833 : : *
834 : : * Also check to see if fullPageWrites was just turned on or there's a
835 : : * running backup (which forces full-page writes); if we weren't
836 : : * already doing full-page writes then go back and recompute.
837 : : *
838 : : * If we aren't doing full-page writes then RedoRecPtr doesn't
839 : : * actually affect the contents of the XLOG record, so we'll update
840 : : * our local copy but not force a recomputation. (If doPageWrites was
841 : : * just turned off, we could recompute the record without full pages,
842 : : * but we choose not to bother.)
843 : : */
844 [ + + ]: 16069331 : if (RedoRecPtr != Insert->RedoRecPtr)
845 : : {
846 [ - + ]: 6901 : Assert(RedoRecPtr < Insert->RedoRecPtr);
847 : 6901 : RedoRecPtr = Insert->RedoRecPtr;
848 : : }
849 [ + + + + ]: 16069331 : doPageWrites = (Insert->fullPageWrites || Insert->runningBackups > 0);
850 : :
851 [ + + ]: 16069331 : if (doPageWrites &&
852 [ + + + + ]: 15819606 : (!prevDoPageWrites ||
129 alvherre@kurilemu.de 853 [ + + ]:GNC 15004186 : (XLogRecPtrIsValid(fpw_lsn) && fpw_lsn <= RedoRecPtr)))
854 : : {
855 : : /*
856 : : * Oops, some buffer now needs to be backed up that the caller
857 : : * didn't back up. Start over.
858 : : */
887 rhaas@postgresql.org 859 :CBC 7604 : WALInsertLockRelease();
860 [ - + ]: 7604 : END_CRIT_SECTION();
861 : 7604 : return InvalidXLogRecPtr;
862 : : }
863 : :
864 : : /*
865 : : * Reserve space for the record in the WAL. This also sets the xl_prev
866 : : * pointer.
867 : : */
4147 heikki.linnakangas@i 868 : 16061727 : ReserveXLogInsertLocation(rechdr->xl_tot_len, &StartPos, &EndPos,
869 : : &rechdr->xl_prev);
870 : :
871 : : /* Normal records are always inserted. */
4633 872 : 16061727 : inserted = true;
873 : : }
878 rhaas@postgresql.org 874 [ + + ]: 1749 : else if (class == WALINSERT_SPECIAL_SWITCH)
875 : : {
876 : : /*
877 : : * In order to insert an XLOG_SWITCH record, we need to hold all of
878 : : * the WAL insertion locks, not just one, so that no one else can
879 : : * begin inserting a record until we've figured out how much space
880 : : * remains in the current WAL segment and claimed all of it.
881 : : *
882 : : * Nonetheless, this case is simpler than the normal cases handled
883 : : * below, which must check for changes in doPageWrites and RedoRecPtr.
884 : : * Those checks are only needed for records that can contain buffer
885 : : * references, and an XLOG_SWITCH record never does.
886 : : */
129 alvherre@kurilemu.de 887 [ - + ]:GNC 816 : Assert(!XLogRecPtrIsValid(fpw_lsn));
887 rhaas@postgresql.org 888 :CBC 816 : WALInsertLockAcquireExclusive();
889 : 816 : inserted = ReserveXLogSwitch(&StartPos, &EndPos, &rechdr->xl_prev);
890 : : }
891 : : else
892 : : {
878 893 [ - + ]: 933 : Assert(class == WALINSERT_SPECIAL_CHECKPOINT);
894 : :
895 : : /*
896 : : * We need to update both the local and shared copies of RedoRecPtr,
897 : : * which means that we need to hold all the WAL insertion locks.
898 : : * However, there can't be any buffer references, so as above, we need
899 : : * not check RedoRecPtr before inserting the record; we just need to
900 : : * update it afterwards.
901 : : */
129 alvherre@kurilemu.de 902 [ - + ]:GNC 933 : Assert(!XLogRecPtrIsValid(fpw_lsn));
878 rhaas@postgresql.org 903 :CBC 933 : WALInsertLockAcquireExclusive();
904 : 933 : ReserveXLogInsertLocation(rechdr->xl_tot_len, &StartPos, &EndPos,
905 : : &rechdr->xl_prev);
906 : 933 : RedoRecPtr = Insert->RedoRecPtr = StartPos;
907 : 933 : inserted = true;
908 : : }
909 : :
4633 heikki.linnakangas@i 910 [ + + ]: 16063476 : if (inserted)
911 : : {
912 : : /*
913 : : * Now that xl_prev has been filled in, calculate CRC of the record
914 : : * header.
915 : : */
4133 916 : 16063409 : rdata_crc = rechdr->xl_crc;
917 : 16063409 : COMP_CRC32C(rdata_crc, rechdr, offsetof(XLogRecord, xl_crc));
4149 918 : 16063409 : FIN_CRC32C(rdata_crc);
4633 919 : 16063409 : rechdr->xl_crc = rdata_crc;
920 : :
921 : : /*
922 : : * All the record data, including the header, is now ready to be
923 : : * inserted. Copy the record in the space reserved.
924 : : */
878 rhaas@postgresql.org 925 : 16063409 : CopyXLogRecordToWAL(rechdr->xl_tot_len,
926 : : class == WALINSERT_SPECIAL_SWITCH, rdata,
927 : : StartPos, EndPos, insertTLI);
928 : :
929 : : /*
930 : : * Unless record is flagged as not important, update LSN of last
931 : : * important record in the current slot. When holding all locks, just
932 : : * update the first one.
933 : : */
3370 andres@anarazel.de 934 [ + + ]: 16063409 : if ((flags & XLOG_MARK_UNIMPORTANT) == 0)
935 : : {
3224 bruce@momjian.us 936 [ + + ]: 15940856 : int lockno = holdingAllLocks ? 0 : MyLockNo;
937 : :
3370 andres@anarazel.de 938 : 15940856 : WALInsertLocks[lockno].l.lastImportantAt = StartPos;
939 : : }
940 : : }
941 : : else
942 : : {
943 : : /*
944 : : * This was an xlog-switch record, but the current insert location was
945 : : * already exactly at the beginning of a segment, so there was no need
946 : : * to do anything.
947 : : */
948 : : }
949 : :
950 : : /*
951 : : * Done! Let others know that we're finished.
952 : : */
4377 heikki.linnakangas@i 953 : 16063476 : WALInsertLockRelease();
954 : :
4633 955 [ - + ]: 16063476 : END_CRIT_SECTION();
956 : :
1594 akapila@postgresql.o 957 : 16063476 : MarkCurrentTransactionIdLoggedIfAny();
958 : :
959 : : /*
960 : : * Mark top transaction id is logged (if needed) so that we should not try
961 : : * to log it again with the next WAL record in the current subtransaction.
962 : : */
963 [ + + ]: 16063476 : if (topxid_included)
964 : 219 : MarkSubxactTopXidLogged();
965 : :
966 : : /*
967 : : * Update shared LogwrtRqst.Write, if we crossed page boundary.
968 : : */
4633 heikki.linnakangas@i 969 [ + + ]: 16063476 : if (StartPos / XLOG_BLCKSZ != EndPos / XLOG_BLCKSZ)
970 : : {
4192 andres@anarazel.de 971 [ + + ]: 1714177 : SpinLockAcquire(&XLogCtl->info_lck);
972 : : /* advance global request to include new block(s) */
973 [ + + ]: 1714177 : if (XLogCtl->LogwrtRqst.Write < EndPos)
974 : 1638033 : XLogCtl->LogwrtRqst.Write = EndPos;
975 : 1714177 : SpinLockRelease(&XLogCtl->info_lck);
709 alvherre@alvh.no-ip. 976 : 1714177 : RefreshXLogWriteResult(LogwrtResult);
977 : : }
978 : :
979 : : /*
980 : : * If this was an XLOG_SWITCH record, flush the record and the empty
981 : : * padding space that fills the rest of the segment, and perform
982 : : * end-of-segment actions (eg, notifying archiver).
983 : : */
878 rhaas@postgresql.org 984 [ + + ]: 16063476 : if (class == WALINSERT_SPECIAL_SWITCH)
985 : : {
986 : : TRACE_POSTGRESQL_WAL_SWITCH();
4633 heikki.linnakangas@i 987 : 816 : XLogFlush(EndPos);
988 : :
989 : : /*
990 : : * Even though we reserved the rest of the segment for us, which is
991 : : * reflected in EndPos, we return a pointer to just the end of the
992 : : * xlog-switch record.
993 : : */
994 [ + + ]: 816 : if (inserted)
995 : : {
996 : 749 : EndPos = StartPos + SizeOfXLogRecord;
997 [ - + ]: 749 : if (StartPos / XLOG_BLCKSZ != EndPos / XLOG_BLCKSZ)
998 : : {
3099 andres@anarazel.de 999 :UBC 0 : uint64 offset = XLogSegmentOffset(EndPos, wal_segment_size);
1000 : :
1001 [ # # ]: 0 : if (offset == EndPos % XLOG_BLCKSZ)
4633 heikki.linnakangas@i 1002 : 0 : EndPos += SizeOfXLogLongPHD;
1003 : : else
1004 : 0 : EndPos += SizeOfXLogShortPHD;
1005 : : }
1006 : : }
1007 : : }
1008 : :
1009 : : #ifdef WAL_DEBUG
1010 : : if (XLOG_DEBUG)
1011 : : {
1012 : : static XLogReaderState *debug_reader = NULL;
1013 : : XLogRecord *record;
1014 : : DecodedXLogRecord *decoded;
1015 : : StringInfoData buf;
1016 : : StringInfoData recordBuf;
1017 : : char *errormsg = NULL;
1018 : : MemoryContext oldCxt;
1019 : :
1020 : : oldCxt = MemoryContextSwitchTo(walDebugCxt);
1021 : :
1022 : : initStringInfo(&buf);
1023 : : appendStringInfo(&buf, "INSERT @ %X/%08X: ", LSN_FORMAT_ARGS(EndPos));
1024 : :
1025 : : /*
1026 : : * We have to piece together the WAL record data from the XLogRecData
1027 : : * entries, so that we can pass it to the rm_desc function as one
1028 : : * contiguous chunk.
1029 : : */
1030 : : initStringInfo(&recordBuf);
1031 : : for (; rdata != NULL; rdata = rdata->next)
1032 : : appendBinaryStringInfo(&recordBuf, rdata->data, rdata->len);
1033 : :
1034 : : /* We also need temporary space to decode the record. */
1035 : : record = (XLogRecord *) recordBuf.data;
1036 : : decoded = (DecodedXLogRecord *)
1037 : : palloc(DecodeXLogRecordRequiredSpace(record->xl_tot_len));
1038 : :
1039 : : if (!debug_reader)
1040 : : debug_reader = XLogReaderAllocate(wal_segment_size, NULL,
1041 : : XL_ROUTINE(.page_read = NULL,
1042 : : .segment_open = NULL,
1043 : : .segment_close = NULL),
1044 : : NULL);
1045 : : if (!debug_reader)
1046 : : {
1047 : : appendStringInfoString(&buf, "error decoding record: out of memory while allocating a WAL reading processor");
1048 : : }
1049 : : else if (!DecodeXLogRecord(debug_reader,
1050 : : decoded,
1051 : : record,
1052 : : EndPos,
1053 : : &errormsg))
1054 : : {
1055 : : appendStringInfo(&buf, "error decoding record: %s",
1056 : : errormsg ? errormsg : "no error message");
1057 : : }
1058 : : else
1059 : : {
1060 : : appendStringInfoString(&buf, " - ");
1061 : :
1062 : : debug_reader->record = decoded;
1063 : : xlog_outdesc(&buf, debug_reader);
1064 : : debug_reader->record = NULL;
1065 : : }
1066 : : elog(LOG, "%s", buf.data);
1067 : :
1068 : : pfree(decoded);
1069 : : pfree(buf.data);
1070 : : pfree(recordBuf.data);
1071 : : MemoryContextSwitchTo(oldCxt);
1072 : : }
1073 : : #endif
1074 : :
1075 : : /*
1076 : : * Update our global variables
1077 : : */
4633 heikki.linnakangas@i 1078 :CBC 16063476 : ProcLastRecPtr = StartPos;
1079 : 16063476 : XactLastRecEnd = EndPos;
1080 : :
1081 : : /* Report WAL traffic to the instrumentation. */
2171 akapila@postgresql.o 1082 [ + + ]: 16063476 : if (inserted)
1083 : : {
1084 : 16063409 : pgWalUsage.wal_bytes += rechdr->xl_tot_len;
1085 : 16063409 : pgWalUsage.wal_records++;
2140 1086 : 16063409 : pgWalUsage.wal_fpi += num_fpi;
137 michael@paquier.xyz 1087 :GNC 16063409 : pgWalUsage.wal_fpi_bytes += fpi_bytes;
1088 : :
1089 : : /* Required for the flush of pending stats WAL data */
230 michael@paquier.xyz 1090 :CBC 16063409 : pgstat_report_fixed = true;
1091 : : }
1092 : :
4633 heikki.linnakangas@i 1093 : 16063476 : return EndPos;
1094 : : }
1095 : :
1096 : : /*
1097 : : * Reserves the right amount of space for a record of given size from the WAL.
1098 : : * *StartPos is set to the beginning of the reserved section, *EndPos to
1099 : : * its end+1. *PrevPtr is set to the beginning of the previous record; it is
1100 : : * used to set the xl_prev of this record.
1101 : : *
1102 : : * This is the performance critical part of XLogInsert that must be serialized
1103 : : * across backends. The rest can happen mostly in parallel. Try to keep this
1104 : : * section as short as possible, insertpos_lck can be heavily contended on a
1105 : : * busy system.
1106 : : *
1107 : : * NB: The space calculation here must match the code in CopyXLogRecordToWAL,
1108 : : * where we actually copy the record to the reserved space.
1109 : : *
1110 : : * NB: Testing shows that XLogInsertRecord runs faster if this code is inlined;
1111 : : * however, because there are two call sites, the compiler is reluctant to
1112 : : * inline. We use pg_attribute_always_inline here to try to convince it.
1113 : : */
1114 : : static pg_attribute_always_inline void
1115 : 16062660 : ReserveXLogInsertLocation(int size, XLogRecPtr *StartPos, XLogRecPtr *EndPos,
1116 : : XLogRecPtr *PrevPtr)
1117 : : {
4192 andres@anarazel.de 1118 : 16062660 : XLogCtlInsert *Insert = &XLogCtl->Insert;
1119 : : uint64 startbytepos;
1120 : : uint64 endbytepos;
1121 : : uint64 prevbytepos;
1122 : :
4633 heikki.linnakangas@i 1123 : 16062660 : size = MAXALIGN(size);
1124 : :
1125 : : /* All (non xlog-switch) records should contain data. */
1126 [ - + ]: 16062660 : Assert(size > SizeOfXLogRecord);
1127 : :
1128 : : /*
1129 : : * The duration the spinlock needs to be held is minimized by minimizing
1130 : : * the calculations that have to be done while holding the lock. The
1131 : : * current tip of reserved WAL is kept in CurrBytePos, as a byte position
1132 : : * that only counts "usable" bytes in WAL, that is, it excludes all WAL
1133 : : * page headers. The mapping between "usable" byte positions and physical
1134 : : * positions (XLogRecPtrs) can be done outside the locked region, and
1135 : : * because the usable byte position doesn't include any headers, reserving
1136 : : * X bytes from WAL is almost as simple as "CurrBytePos += X".
1137 : : */
1138 [ + + ]: 16062660 : SpinLockAcquire(&Insert->insertpos_lck);
1139 : :
1140 : 16062660 : startbytepos = Insert->CurrBytePos;
1141 : 16062660 : endbytepos = startbytepos + size;
1142 : 16062660 : prevbytepos = Insert->PrevBytePos;
1143 : 16062660 : Insert->CurrBytePos = endbytepos;
1144 : 16062660 : Insert->PrevBytePos = startbytepos;
1145 : :
1146 : 16062660 : SpinLockRelease(&Insert->insertpos_lck);
1147 : :
1148 : 16062660 : *StartPos = XLogBytePosToRecPtr(startbytepos);
1149 : 16062660 : *EndPos = XLogBytePosToEndRecPtr(endbytepos);
1150 : 16062660 : *PrevPtr = XLogBytePosToRecPtr(prevbytepos);
1151 : :
1152 : : /*
1153 : : * Check that the conversions between "usable byte positions" and
1154 : : * XLogRecPtrs work consistently in both directions.
1155 : : */
1156 [ - + ]: 16062660 : Assert(XLogRecPtrToBytePos(*StartPos) == startbytepos);
1157 [ - + ]: 16062660 : Assert(XLogRecPtrToBytePos(*EndPos) == endbytepos);
1158 [ - + ]: 16062660 : Assert(XLogRecPtrToBytePos(*PrevPtr) == prevbytepos);
1159 : 16062660 : }
1160 : :
1161 : : /*
1162 : : * Like ReserveXLogInsertLocation(), but for an xlog-switch record.
1163 : : *
1164 : : * A log-switch record is handled slightly differently. The rest of the
1165 : : * segment will be reserved for this insertion, as indicated by the returned
1166 : : * *EndPos value. However, if we are already at the beginning of the current
1167 : : * segment, *StartPos and *EndPos are set to the current location without
1168 : : * reserving any space, and the function returns false.
1169 : : */
1170 : : static bool
1171 : 816 : ReserveXLogSwitch(XLogRecPtr *StartPos, XLogRecPtr *EndPos, XLogRecPtr *PrevPtr)
1172 : : {
4192 andres@anarazel.de 1173 : 816 : XLogCtlInsert *Insert = &XLogCtl->Insert;
1174 : : uint64 startbytepos;
1175 : : uint64 endbytepos;
1176 : : uint64 prevbytepos;
4133 heikki.linnakangas@i 1177 : 816 : uint32 size = MAXALIGN(SizeOfXLogRecord);
1178 : : XLogRecPtr ptr;
1179 : : uint32 segleft;
1180 : :
1181 : : /*
1182 : : * These calculations are a bit heavy-weight to be done while holding a
1183 : : * spinlock, but since we're holding all the WAL insertion locks, there
1184 : : * are no other inserters competing for it. GetXLogInsertRecPtr() does
1185 : : * compete for it, but that's not called very frequently.
1186 : : */
4633 1187 [ - + ]: 816 : SpinLockAcquire(&Insert->insertpos_lck);
1188 : :
1189 : 816 : startbytepos = Insert->CurrBytePos;
1190 : :
1191 : 816 : ptr = XLogBytePosToEndRecPtr(startbytepos);
3099 andres@anarazel.de 1192 [ + + ]: 816 : if (XLogSegmentOffset(ptr, wal_segment_size) == 0)
1193 : : {
4633 heikki.linnakangas@i 1194 : 67 : SpinLockRelease(&Insert->insertpos_lck);
1195 : 67 : *EndPos = *StartPos = ptr;
1196 : 67 : return false;
1197 : : }
1198 : :
1199 : 749 : endbytepos = startbytepos + size;
1200 : 749 : prevbytepos = Insert->PrevBytePos;
1201 : :
1202 : 749 : *StartPos = XLogBytePosToRecPtr(startbytepos);
1203 : 749 : *EndPos = XLogBytePosToEndRecPtr(endbytepos);
1204 : :
3099 andres@anarazel.de 1205 : 749 : segleft = wal_segment_size - XLogSegmentOffset(*EndPos, wal_segment_size);
1206 [ + - ]: 749 : if (segleft != wal_segment_size)
1207 : : {
1208 : : /* consume the rest of the segment */
4633 heikki.linnakangas@i 1209 : 749 : *EndPos += segleft;
1210 : 749 : endbytepos = XLogRecPtrToBytePos(*EndPos);
1211 : : }
1212 : 749 : Insert->CurrBytePos = endbytepos;
1213 : 749 : Insert->PrevBytePos = startbytepos;
1214 : :
1215 : 749 : SpinLockRelease(&Insert->insertpos_lck);
1216 : :
1217 : 749 : *PrevPtr = XLogBytePosToRecPtr(prevbytepos);
1218 : :
3099 andres@anarazel.de 1219 [ - + ]: 749 : Assert(XLogSegmentOffset(*EndPos, wal_segment_size) == 0);
4633 heikki.linnakangas@i 1220 [ - + ]: 749 : Assert(XLogRecPtrToBytePos(*EndPos) == endbytepos);
1221 [ - + ]: 749 : Assert(XLogRecPtrToBytePos(*StartPos) == startbytepos);
1222 [ - + ]: 749 : Assert(XLogRecPtrToBytePos(*PrevPtr) == prevbytepos);
1223 : :
1224 : 749 : return true;
1225 : : }
1226 : :
1227 : : /*
1228 : : * Subroutine of XLogInsertRecord. Copies a WAL record to an already-reserved
1229 : : * area in the WAL.
1230 : : */
1231 : : static void
1232 : 16063409 : CopyXLogRecordToWAL(int write_len, bool isLogSwitch, XLogRecData *rdata,
1233 : : XLogRecPtr StartPos, XLogRecPtr EndPos, TimeLineID tli)
1234 : : {
1235 : : char *currpos;
1236 : : int freespace;
1237 : : int written;
1238 : : XLogRecPtr CurrPos;
1239 : : XLogPageHeader pagehdr;
1240 : :
1241 : : /*
1242 : : * Get a pointer to the right place in the right WAL buffer to start
1243 : : * inserting to.
1244 : : */
1245 : 16063409 : CurrPos = StartPos;
1591 rhaas@postgresql.org 1246 : 16063409 : currpos = GetXLogBuffer(CurrPos, tli);
4633 heikki.linnakangas@i 1247 [ + - ]: 16063409 : freespace = INSERT_FREESPACE(CurrPos);
1248 : :
1249 : : /*
1250 : : * there should be enough space for at least the first field (xl_tot_len)
1251 : : * on this page.
1252 : : */
1253 [ - + ]: 16063409 : Assert(freespace >= sizeof(uint32));
1254 : :
1255 : : /* Copy record data */
1256 : 16063409 : written = 0;
1257 [ + + ]: 76446720 : while (rdata != NULL)
1258 : : {
558 peter@eisentraut.org 1259 : 60383311 : const char *rdata_data = rdata->data;
4633 heikki.linnakangas@i 1260 : 60383311 : int rdata_len = rdata->len;
1261 : :
1262 [ + + ]: 62212474 : while (rdata_len > freespace)
1263 : : {
1264 : : /*
1265 : : * Write what fits on this page, and continue on the next page.
1266 : : */
1267 [ + + - + ]: 1829163 : Assert(CurrPos % XLOG_BLCKSZ >= SizeOfXLogShortPHD || freespace == 0);
1268 : 1829163 : memcpy(currpos, rdata_data, freespace);
1269 : 1829163 : rdata_data += freespace;
1270 : 1829163 : rdata_len -= freespace;
1271 : 1829163 : written += freespace;
1272 : 1829163 : CurrPos += freespace;
1273 : :
1274 : : /*
1275 : : * Get pointer to beginning of next page, and set the xlp_rem_len
1276 : : * in the page header. Set XLP_FIRST_IS_CONTRECORD.
1277 : : *
1278 : : * It's safe to set the contrecord flag and xlp_rem_len without a
1279 : : * lock on the page. All the other flags were already set when the
1280 : : * page was initialized, in AdvanceXLInsertBuffer, and we're the
1281 : : * only backend that needs to set the contrecord flag.
1282 : : */
1591 rhaas@postgresql.org 1283 : 1829163 : currpos = GetXLogBuffer(CurrPos, tli);
4633 heikki.linnakangas@i 1284 : 1829163 : pagehdr = (XLogPageHeader) currpos;
1285 : 1829163 : pagehdr->xlp_rem_len = write_len - written;
1286 : 1829163 : pagehdr->xlp_info |= XLP_FIRST_IS_CONTRECORD;
1287 : :
1288 : : /* skip over the page header */
3099 andres@anarazel.de 1289 [ + + ]: 1829163 : if (XLogSegmentOffset(CurrPos, wal_segment_size) == 0)
1290 : : {
4633 heikki.linnakangas@i 1291 : 1206 : CurrPos += SizeOfXLogLongPHD;
1292 : 1206 : currpos += SizeOfXLogLongPHD;
1293 : : }
1294 : : else
1295 : : {
1296 : 1827957 : CurrPos += SizeOfXLogShortPHD;
1297 : 1827957 : currpos += SizeOfXLogShortPHD;
1298 : : }
1299 [ + - ]: 1829163 : freespace = INSERT_FREESPACE(CurrPos);
1300 : : }
1301 : :
1302 [ - + - - ]: 60383311 : Assert(CurrPos % XLOG_BLCKSZ >= SizeOfXLogShortPHD || rdata_len == 0);
1303 : 60383311 : memcpy(currpos, rdata_data, rdata_len);
1304 : 60383311 : currpos += rdata_len;
1305 : 60383311 : CurrPos += rdata_len;
1306 : 60383311 : freespace -= rdata_len;
1307 : 60383311 : written += rdata_len;
1308 : :
1309 : 60383311 : rdata = rdata->next;
1310 : : }
1311 [ - + ]: 16063409 : Assert(written == write_len);
1312 : :
1313 : : /*
1314 : : * If this was an xlog-switch, it's not enough to write the switch record,
1315 : : * we also have to consume all the remaining space in the WAL segment. We
1316 : : * have already reserved that space, but we need to actually fill it.
1317 : : */
3099 andres@anarazel.de 1318 [ + + + - ]: 16063409 : if (isLogSwitch && XLogSegmentOffset(CurrPos, wal_segment_size) != 0)
1319 : : {
1320 : : /* An xlog-switch record doesn't contain any data besides the header */
4633 heikki.linnakangas@i 1321 [ - + ]: 749 : Assert(write_len == SizeOfXLogRecord);
1322 : :
1323 : : /* Assert that we did reserve the right amount of space */
3099 andres@anarazel.de 1324 [ - + ]: 749 : Assert(XLogSegmentOffset(EndPos, wal_segment_size) == 0);
1325 : :
1326 : : /* Use up all the remaining space on the current page */
4633 heikki.linnakangas@i 1327 : 749 : CurrPos += freespace;
1328 : :
1329 : : /*
1330 : : * Cause all remaining pages in the segment to be flushed, leaving the
1331 : : * XLog position where it should be, at the start of the next segment.
1332 : : * We do this one page at a time, to make sure we don't deadlock
1333 : : * against ourselves if wal_buffers < wal_segment_size.
1334 : : */
1335 [ + + ]: 743260 : while (CurrPos < EndPos)
1336 : : {
1337 : : /*
1338 : : * The minimal action to flush the page would be to call
1339 : : * WALInsertLockUpdateInsertingAt(CurrPos) followed by
1340 : : * AdvanceXLInsertBuffer(...). The page would be left initialized
1341 : : * mostly to zeros, except for the page header (always the short
1342 : : * variant, as this is never a segment's first page).
1343 : : *
1344 : : * The large vistas of zeros are good for compressibility, but the
1345 : : * headers interrupting them every XLOG_BLCKSZ (with values that
1346 : : * differ from page to page) are not. The effect varies with
1347 : : * compression tool, but bzip2 for instance compresses about an
1348 : : * order of magnitude worse if those headers are left in place.
1349 : : *
1350 : : * Rather than complicating AdvanceXLInsertBuffer itself (which is
1351 : : * called in heavily-loaded circumstances as well as this lightly-
1352 : : * loaded one) with variant behavior, we just use GetXLogBuffer
1353 : : * (which itself calls the two methods we need) to get the pointer
1354 : : * and zero most of the page. Then we just zero the page header.
1355 : : */
1591 rhaas@postgresql.org 1356 : 742511 : currpos = GetXLogBuffer(CurrPos, tli);
2907 tgl@sss.pgh.pa.us 1357 [ + - + - : 2970044 : MemSet(currpos, 0, SizeOfXLogShortPHD);
+ - + - +
+ ]
1358 : :
4633 heikki.linnakangas@i 1359 : 742511 : CurrPos += XLOG_BLCKSZ;
1360 : : }
1361 : : }
1362 : : else
1363 : : {
1364 : : /* Align the end position, so that the next record starts aligned */
4133 1365 : 16062660 : CurrPos = MAXALIGN64(CurrPos);
1366 : : }
1367 : :
4633 1368 [ - + ]: 16063409 : if (CurrPos != EndPos)
711 dgustafsson@postgres 1369 [ # # ]:UBC 0 : ereport(PANIC,
1370 : : errcode(ERRCODE_DATA_CORRUPTED),
1371 : : errmsg_internal("space reserved for WAL record does not match what was written"));
4633 heikki.linnakangas@i 1372 :CBC 16063409 : }
1373 : :
1374 : : /*
1375 : : * Acquire a WAL insertion lock, for inserting to WAL.
1376 : : */
1377 : : static void
4377 1378 : 16069343 : WALInsertLockAcquire(void)
1379 : : {
1380 : : bool immed;
1381 : :
1382 : : /*
1383 : : * It doesn't matter which of the WAL insertion locks we acquire, so try
1384 : : * the one we used last time. If the system isn't particularly busy, it's
1385 : : * a good bet that it's still available, and it's good to have some
1386 : : * affinity to a particular lock so that you don't unnecessarily bounce
1387 : : * cache lines between processes when there's no contention.
1388 : : *
1389 : : * If this is the first time through in this backend, pick a lock
1390 : : * (semi-)randomly. This allows the locks to be used evenly if you have a
1391 : : * lot of very short connections.
1392 : : */
1393 : : static int lockToTry = -1;
1394 : :
1395 [ + + ]: 16069343 : if (lockToTry == -1)
752 1396 : 8026 : lockToTry = MyProcNumber % NUM_XLOGINSERT_LOCKS;
4377 1397 : 16069343 : MyLockNo = lockToTry;
1398 : :
1399 : : /*
1400 : : * The insertingAt value is initially set to 0, as we don't know our
1401 : : * insert location yet.
1402 : : */
3880 andres@anarazel.de 1403 : 16069343 : immed = LWLockAcquire(&WALInsertLocks[MyLockNo].l.lock, LW_EXCLUSIVE);
4377 heikki.linnakangas@i 1404 [ + + ]: 16069343 : if (!immed)
1405 : : {
1406 : : /*
1407 : : * If we couldn't get the lock immediately, try another lock next
1408 : : * time. On a system with more insertion locks than concurrent
1409 : : * inserters, this causes all the inserters to eventually migrate to a
1410 : : * lock that no-one else is using. On a system with more inserters
1411 : : * than locks, it still helps to distribute the inserters evenly
1412 : : * across the locks.
1413 : : */
4183 1414 : 21031 : lockToTry = (lockToTry + 1) % NUM_XLOGINSERT_LOCKS;
1415 : : }
4633 1416 : 16069343 : }
1417 : :
1418 : : /*
1419 : : * Acquire all WAL insertion locks, to prevent other backends from inserting
1420 : : * to WAL.
1421 : : */
1422 : : static void
4377 1423 : 4644 : WALInsertLockAcquireExclusive(void)
1424 : : {
1425 : : int i;
1426 : :
1427 : : /*
1428 : : * When holding all the locks, all but the last lock's insertingAt
1429 : : * indicator is set to 0xFFFFFFFFFFFFFFFF, which is higher than any real
1430 : : * XLogRecPtr value, to make sure that no-one blocks waiting on those.
1431 : : */
4183 1432 [ + + ]: 37152 : for (i = 0; i < NUM_XLOGINSERT_LOCKS - 1; i++)
1433 : : {
3880 andres@anarazel.de 1434 : 32508 : LWLockAcquire(&WALInsertLocks[i].l.lock, LW_EXCLUSIVE);
1435 : 32508 : LWLockUpdateVar(&WALInsertLocks[i].l.lock,
1436 : 32508 : &WALInsertLocks[i].l.insertingAt,
1437 : : PG_UINT64_MAX);
1438 : : }
1439 : : /* Variable value reset to 0 at release */
1440 : 4644 : LWLockAcquire(&WALInsertLocks[i].l.lock, LW_EXCLUSIVE);
1441 : :
4377 heikki.linnakangas@i 1442 : 4644 : holdingAllLocks = true;
4633 1443 : 4644 : }
1444 : :
1445 : : /*
1446 : : * Release our insertion lock (or locks, if we're holding them all).
1447 : : *
1448 : : * NB: Reset all variables to 0, so they cause LWLockWaitForVar to block the
1449 : : * next time the lock is acquired.
1450 : : */
1451 : : static void
4377 1452 : 16073987 : WALInsertLockRelease(void)
1453 : : {
1454 [ + + ]: 16073987 : if (holdingAllLocks)
1455 : : {
1456 : : int i;
1457 : :
4183 1458 [ + + ]: 41796 : for (i = 0; i < NUM_XLOGINSERT_LOCKS; i++)
3880 andres@anarazel.de 1459 : 37152 : LWLockReleaseClearVar(&WALInsertLocks[i].l.lock,
1460 : 37152 : &WALInsertLocks[i].l.insertingAt,
1461 : : 0);
1462 : :
4377 heikki.linnakangas@i 1463 : 4644 : holdingAllLocks = false;
1464 : : }
1465 : : else
1466 : : {
3880 andres@anarazel.de 1467 : 16069343 : LWLockReleaseClearVar(&WALInsertLocks[MyLockNo].l.lock,
1468 : 16069343 : &WALInsertLocks[MyLockNo].l.insertingAt,
1469 : : 0);
1470 : : }
4633 heikki.linnakangas@i 1471 : 16073987 : }
1472 : :
1473 : : /*
1474 : : * Update our insertingAt value, to let others know that we've finished
1475 : : * inserting up to that point.
1476 : : */
1477 : : static void
4377 1478 : 2505029 : WALInsertLockUpdateInsertingAt(XLogRecPtr insertingAt)
1479 : : {
1480 [ + + ]: 2505029 : if (holdingAllLocks)
1481 : : {
1482 : : /*
1483 : : * We use the last lock to mark our actual position, see comments in
1484 : : * WALInsertLockAcquireExclusive.
1485 : : */
4183 1486 : 742659 : LWLockUpdateVar(&WALInsertLocks[NUM_XLOGINSERT_LOCKS - 1].l.lock,
3189 tgl@sss.pgh.pa.us 1487 : 742659 : &WALInsertLocks[NUM_XLOGINSERT_LOCKS - 1].l.insertingAt,
1488 : : insertingAt);
1489 : : }
1490 : : else
4377 heikki.linnakangas@i 1491 : 1762370 : LWLockUpdateVar(&WALInsertLocks[MyLockNo].l.lock,
1492 : 1762370 : &WALInsertLocks[MyLockNo].l.insertingAt,
1493 : : insertingAt);
4633 1494 : 2505029 : }
1495 : :
1496 : : /*
1497 : : * Wait for any WAL insertions < upto to finish.
1498 : : *
1499 : : * Returns the location of the oldest insertion that is still in-progress.
1500 : : * Any WAL prior to that point has been fully copied into WAL buffers, and
1501 : : * can be flushed out to disk. Because this waits for any insertions older
1502 : : * than 'upto' to finish, the return value is always >= 'upto'.
1503 : : *
1504 : : * Note: When you are about to write out WAL, you must call this function
1505 : : * *before* acquiring WALWriteLock, to avoid deadlocks. This function might
1506 : : * need to wait for an insertion to finish (or at least advance to next
1507 : : * uninitialized page), and the inserter might need to evict an old WAL buffer
1508 : : * to make room for a new one, which in turn requires WALWriteLock.
1509 : : */
1510 : : static XLogRecPtr
1511 : 2362773 : WaitXLogInsertionsToFinish(XLogRecPtr upto)
1512 : : {
1513 : : uint64 bytepos;
1514 : : XLogRecPtr inserted;
1515 : : XLogRecPtr reservedUpto;
1516 : : XLogRecPtr finishedUpto;
4192 andres@anarazel.de 1517 : 2362773 : XLogCtlInsert *Insert = &XLogCtl->Insert;
1518 : : int i;
1519 : :
4633 heikki.linnakangas@i 1520 [ - + ]: 2362773 : if (MyProc == NULL)
4633 heikki.linnakangas@i 1521 [ # # ]:UBC 0 : elog(PANIC, "cannot wait without a PGPROC structure");
1522 : :
1523 : : /*
1524 : : * Check if there's any work to do. Use a barrier to ensure we get the
1525 : : * freshest value.
1526 : : */
707 alvherre@alvh.no-ip. 1527 :CBC 2362773 : inserted = pg_atomic_read_membarrier_u64(&XLogCtl->logInsertResult);
1528 [ + + ]: 2362773 : if (upto <= inserted)
1529 : 1868172 : return inserted;
1530 : :
1531 : : /* Read the current insert position */
4633 heikki.linnakangas@i 1532 [ + + ]: 494601 : SpinLockAcquire(&Insert->insertpos_lck);
1533 : 494601 : bytepos = Insert->CurrBytePos;
1534 : 494601 : SpinLockRelease(&Insert->insertpos_lck);
1535 : 494601 : reservedUpto = XLogBytePosToEndRecPtr(bytepos);
1536 : :
1537 : : /*
1538 : : * No-one should request to flush a piece of WAL that hasn't even been
1539 : : * reserved yet. However, it can happen if there is a block with a bogus
1540 : : * LSN on disk, for example. XLogFlush checks for that situation and
1541 : : * complains, but only after the flush. Here we just assume that to mean
1542 : : * that all WAL that has been reserved needs to be finished. In this
1543 : : * corner-case, the return value can be smaller than 'upto' argument.
1544 : : */
1545 [ - + ]: 494601 : if (upto > reservedUpto)
1546 : : {
1927 peter@eisentraut.org 1547 [ # # ]:UBC 0 : ereport(LOG,
1548 : : errmsg("request to flush past end of generated WAL; request %X/%08X, current position %X/%08X",
1549 : : LSN_FORMAT_ARGS(upto), LSN_FORMAT_ARGS(reservedUpto)));
4633 heikki.linnakangas@i 1550 : 0 : upto = reservedUpto;
1551 : : }
1552 : :
1553 : : /*
1554 : : * Loop through all the locks, sleeping on any in-progress insert older
1555 : : * than 'upto'.
1556 : : *
1557 : : * finishedUpto is our return value, indicating the point upto which all
1558 : : * the WAL insertions have been finished. Initialize it to the head of
1559 : : * reserved WAL, and as we iterate through the insertion locks, back it
1560 : : * out for any insertion that's still in progress.
1561 : : */
4633 heikki.linnakangas@i 1562 :CBC 494601 : finishedUpto = reservedUpto;
4183 1563 [ + + ]: 4451409 : for (i = 0; i < NUM_XLOGINSERT_LOCKS; i++)
1564 : : {
4331 bruce@momjian.us 1565 : 3956808 : XLogRecPtr insertingat = InvalidXLogRecPtr;
1566 : :
1567 : : do
1568 : : {
1569 : : /*
1570 : : * See if this insertion is in progress. LWLockWaitForVar will
1571 : : * wait for the lock to be released, or for the 'value' to be set
1572 : : * by a LWLockUpdateVar call. When a lock is initially acquired,
1573 : : * its value is 0 (InvalidXLogRecPtr), which means that we don't
1574 : : * know where it's inserting yet. We will have to wait for it. If
1575 : : * it's a small insertion, the record will most likely fit on the
1576 : : * same page and the inserter will release the lock without ever
1577 : : * calling LWLockUpdateVar. But if it has to sleep, it will
1578 : : * advertise the insertion point with LWLockUpdateVar before
1579 : : * sleeping.
1580 : : *
1581 : : * In this loop we are only waiting for insertions that started
1582 : : * before WaitXLogInsertionsToFinish was called. The lack of
1583 : : * memory barriers in the loop means that we might see locks as
1584 : : * "unused" that have since become used. This is fine because
1585 : : * they only can be used for later insertions that we would not
1586 : : * want to wait on anyway. Not taking a lock to acquire the
1587 : : * current insertingAt value means that we might see older
1588 : : * insertingAt values. This is also fine, because if we read a
1589 : : * value too old, we will add ourselves to the wait queue, which
1590 : : * contains atomic operations.
1591 : : */
4377 heikki.linnakangas@i 1592 [ + + ]: 4102213 : if (LWLockWaitForVar(&WALInsertLocks[i].l.lock,
1593 : 4102213 : &WALInsertLocks[i].l.insertingAt,
1594 : : insertingat, &insertingat))
1595 : : {
1596 : : /* the lock was free, so no insertion in progress */
1597 : 2678270 : insertingat = InvalidXLogRecPtr;
1598 : 2678270 : break;
1599 : : }
1600 : :
1601 : : /*
1602 : : * This insertion is still in progress. Have to wait, unless the
1603 : : * inserter has proceeded past 'upto'.
1604 : : */
1605 [ + + ]: 1423943 : } while (insertingat < upto);
1606 : :
129 alvherre@kurilemu.de 1607 [ + + + + ]:GNC 3956808 : if (XLogRecPtrIsValid(insertingat) && insertingat < finishedUpto)
4377 heikki.linnakangas@i 1608 :CBC 450696 : finishedUpto = insertingat;
1609 : : }
1610 : :
1611 : : /*
1612 : : * Advance the limit we know to have been inserted and return the freshest
1613 : : * value we know of, which might be beyond what we requested if somebody
1614 : : * is concurrently doing this with an 'upto' pointer ahead of us.
1615 : : */
707 alvherre@alvh.no-ip. 1616 : 494601 : finishedUpto = pg_atomic_monotonic_advance_u64(&XLogCtl->logInsertResult,
1617 : : finishedUpto);
1618 : :
4633 heikki.linnakangas@i 1619 : 494601 : return finishedUpto;
1620 : : }
1621 : :
1622 : : /*
1623 : : * Get a pointer to the right location in the WAL buffer containing the
1624 : : * given XLogRecPtr.
1625 : : *
1626 : : * If the page is not initialized yet, it is initialized. That might require
1627 : : * evicting an old dirty buffer from the buffer cache, which means I/O.
1628 : : *
1629 : : * The caller must ensure that the page containing the requested location
1630 : : * isn't evicted yet, and won't be evicted. The way to ensure that is to
1631 : : * hold onto a WAL insertion lock with the insertingAt position set to
1632 : : * something <= ptr. GetXLogBuffer() will update insertingAt if it needs
1633 : : * to evict an old page from the buffer. (This means that once you call
1634 : : * GetXLogBuffer() with a given 'ptr', you must not access anything before
1635 : : * that point anymore, and must not call GetXLogBuffer() with an older 'ptr'
1636 : : * later, because older buffers might be recycled already)
1637 : : */
1638 : : static char *
1591 rhaas@postgresql.org 1639 : 18635095 : GetXLogBuffer(XLogRecPtr ptr, TimeLineID tli)
1640 : : {
1641 : : int idx;
1642 : : XLogRecPtr endptr;
1643 : : static uint64 cachedPage = 0;
1644 : : static char *cachedPos = NULL;
1645 : : XLogRecPtr expectedEndPtr;
1646 : :
1647 : : /*
1648 : : * Fast path for the common case that we need to access again the same
1649 : : * page as last time.
1650 : : */
4633 heikki.linnakangas@i 1651 [ + + ]: 18635095 : if (ptr / XLOG_BLCKSZ == cachedPage)
1652 : : {
1653 [ - + ]: 15678529 : Assert(((XLogPageHeader) cachedPos)->xlp_magic == XLOG_PAGE_MAGIC);
1654 [ - + ]: 15678529 : Assert(((XLogPageHeader) cachedPos)->xlp_pageaddr == ptr - (ptr % XLOG_BLCKSZ));
1655 : 15678529 : return cachedPos + ptr % XLOG_BLCKSZ;
1656 : : }
1657 : :
1658 : : /*
1659 : : * The XLog buffer cache is organized so that a page is always loaded to a
1660 : : * particular buffer. That way we can easily calculate the buffer a given
1661 : : * page must be loaded into, from the XLogRecPtr alone.
1662 : : */
1663 : 2956566 : idx = XLogRecPtrToBufIdx(ptr);
1664 : :
1665 : : /*
1666 : : * See what page is loaded in the buffer at the moment. It could be the
1667 : : * page we're looking for, or something older. It can't be anything newer
1668 : : * - that would imply the page we're looking for has already been written
1669 : : * out to disk and evicted, and the caller is responsible for making sure
1670 : : * that doesn't happen.
1671 : : *
1672 : : * We don't hold a lock while we read the value. If someone is just about
1673 : : * to initialize or has just initialized the page, it's possible that we
1674 : : * get InvalidXLogRecPtr. That's ok, we'll grab the mapping lock (in
1675 : : * AdvanceXLInsertBuffer) and retry if we see anything other than the page
1676 : : * we're looking for.
1677 : : */
1678 : 2956566 : expectedEndPtr = ptr;
1679 : 2956566 : expectedEndPtr += XLOG_BLCKSZ - ptr % XLOG_BLCKSZ;
1680 : :
817 jdavis@postgresql.or 1681 : 2956566 : endptr = pg_atomic_read_u64(&XLogCtl->xlblocks[idx]);
4633 heikki.linnakangas@i 1682 [ + + ]: 2956566 : if (expectedEndPtr != endptr)
1683 : : {
1684 : : XLogRecPtr initializedUpto;
1685 : :
1686 : : /*
1687 : : * Before calling AdvanceXLInsertBuffer(), which can block, let others
1688 : : * know how far we're finished with inserting the record.
1689 : : *
1690 : : * NB: If 'ptr' points to just after the page header, advertise a
1691 : : * position at the beginning of the page rather than 'ptr' itself. If
1692 : : * there are no other insertions running, someone might try to flush
1693 : : * up to our advertised location. If we advertised a position after
1694 : : * the page header, someone might try to flush the page header, even
1695 : : * though page might actually not be initialized yet. As the first
1696 : : * inserter on the page, we are effectively responsible for making
1697 : : * sure that it's initialized, before we let insertingAt to move past
1698 : : * the page header.
1699 : : */
3878 1700 [ + + ]: 2505029 : if (ptr % XLOG_BLCKSZ == SizeOfXLogShortPHD &&
3099 andres@anarazel.de 1701 [ + - ]: 5404 : XLogSegmentOffset(ptr, wal_segment_size) > XLOG_BLCKSZ)
3878 heikki.linnakangas@i 1702 : 5404 : initializedUpto = ptr - SizeOfXLogShortPHD;
1703 [ + + ]: 2499625 : else if (ptr % XLOG_BLCKSZ == SizeOfXLogLongPHD &&
3099 andres@anarazel.de 1704 [ + + ]: 888 : XLogSegmentOffset(ptr, wal_segment_size) < XLOG_BLCKSZ)
3878 heikki.linnakangas@i 1705 : 620 : initializedUpto = ptr - SizeOfXLogLongPHD;
1706 : : else
1707 : 2499005 : initializedUpto = ptr;
1708 : :
1709 : 2505029 : WALInsertLockUpdateInsertingAt(initializedUpto);
1710 : :
1591 rhaas@postgresql.org 1711 : 2505029 : AdvanceXLInsertBuffer(ptr, tli, false);
817 jdavis@postgresql.or 1712 : 2505029 : endptr = pg_atomic_read_u64(&XLogCtl->xlblocks[idx]);
1713 : :
4633 heikki.linnakangas@i 1714 [ - + ]: 2505029 : if (expectedEndPtr != endptr)
251 alvherre@kurilemu.de 1715 [ # # ]:UNC 0 : elog(PANIC, "could not find WAL buffer for %X/%08X",
1716 : : LSN_FORMAT_ARGS(ptr));
1717 : : }
1718 : : else
1719 : : {
1720 : : /*
1721 : : * Make sure the initialization of the page is visible to us, and
1722 : : * won't arrive later to overwrite the WAL data we write on the page.
1723 : : */
4633 heikki.linnakangas@i 1724 :CBC 451537 : pg_memory_barrier();
1725 : : }
1726 : :
1727 : : /*
1728 : : * Found the buffer holding this page. Return a pointer to the right
1729 : : * offset within the page.
1730 : : */
1731 : 2956566 : cachedPage = ptr / XLOG_BLCKSZ;
1732 : 2956566 : cachedPos = XLogCtl->pages + idx * (Size) XLOG_BLCKSZ;
1733 : :
1734 [ - + ]: 2956566 : Assert(((XLogPageHeader) cachedPos)->xlp_magic == XLOG_PAGE_MAGIC);
1735 [ - + ]: 2956566 : Assert(((XLogPageHeader) cachedPos)->xlp_pageaddr == ptr - (ptr % XLOG_BLCKSZ));
1736 : :
1737 : 2956566 : return cachedPos + ptr % XLOG_BLCKSZ;
1738 : : }
1739 : :
1740 : : /*
1741 : : * Read WAL data directly from WAL buffers, if available. Returns the number
1742 : : * of bytes read successfully.
1743 : : *
1744 : : * Fewer than 'count' bytes may be read if some of the requested WAL data has
1745 : : * already been evicted.
1746 : : *
1747 : : * No locks are taken.
1748 : : *
1749 : : * Caller should ensure that it reads no further than LogwrtResult.Write
1750 : : * (which should have been updated by the caller when determining how far to
1751 : : * read). The 'tli' argument is only used as a convenient safety check so that
1752 : : * callers do not read from WAL buffers on a historical timeline.
1753 : : */
1754 : : Size
762 jdavis@postgresql.or 1755 : 104160 : WALReadFromBuffers(char *dstbuf, XLogRecPtr startptr, Size count,
1756 : : TimeLineID tli)
1757 : : {
1758 : 104160 : char *pdst = dstbuf;
1759 : 104160 : XLogRecPtr recptr = startptr;
1760 : : XLogRecPtr inserted;
758 1761 : 104160 : Size nbytes = count;
1762 : :
762 1763 [ + + + + ]: 104160 : if (RecoveryInProgress() || tli != GetWALInsertionTimeLine())
1764 : 912 : return 0;
1765 : :
129 alvherre@kurilemu.de 1766 [ - + ]:GNC 103248 : Assert(XLogRecPtrIsValid(startptr));
1767 : :
1768 : : /*
1769 : : * Caller should ensure that the requested data has been inserted into WAL
1770 : : * buffers before we try to read it.
1771 : : */
707 alvherre@alvh.no-ip. 1772 :CBC 103248 : inserted = pg_atomic_read_u64(&XLogCtl->logInsertResult);
1773 [ - + ]: 103248 : if (startptr + count > inserted)
707 alvherre@alvh.no-ip. 1774 [ # # ]:UBC 0 : ereport(ERROR,
1775 : : errmsg("cannot read past end of generated WAL: requested %X/%08X, current position %X/%08X",
1776 : : LSN_FORMAT_ARGS(startptr + count),
1777 : : LSN_FORMAT_ARGS(inserted)));
1778 : :
1779 : : /*
1780 : : * Loop through the buffers without a lock. For each buffer, atomically
1781 : : * read and verify the end pointer, then copy the data out, and finally
1782 : : * re-read and re-verify the end pointer.
1783 : : *
1784 : : * Once a page is evicted, it never returns to the WAL buffers, so if the
1785 : : * end pointer matches the expected end pointer before and after we copy
1786 : : * the data, then the right page must have been present during the data
1787 : : * copy. Read barriers are necessary to ensure that the data copy actually
1788 : : * happens between the two verification steps.
1789 : : *
1790 : : * If either verification fails, we simply terminate the loop and return
1791 : : * with the data that had been already copied out successfully.
1792 : : */
762 jdavis@postgresql.or 1793 [ + + ]:CBC 129703 : while (nbytes > 0)
1794 : : {
1795 : 122059 : uint32 offset = recptr % XLOG_BLCKSZ;
1796 : 122059 : int idx = XLogRecPtrToBufIdx(recptr);
1797 : : XLogRecPtr expectedEndPtr;
1798 : : XLogRecPtr endptr;
1799 : : const char *page;
1800 : : const char *psrc;
1801 : : Size npagebytes;
1802 : :
1803 : : /*
1804 : : * Calculate the end pointer we expect in the xlblocks array if the
1805 : : * correct page is present.
1806 : : */
1807 : 122059 : expectedEndPtr = recptr + (XLOG_BLCKSZ - offset);
1808 : :
1809 : : /*
1810 : : * First verification step: check that the correct page is present in
1811 : : * the WAL buffers.
1812 : : */
1813 : 122059 : endptr = pg_atomic_read_u64(&XLogCtl->xlblocks[idx]);
1814 [ + + ]: 122059 : if (expectedEndPtr != endptr)
1815 : 95604 : break;
1816 : :
1817 : : /*
1818 : : * The correct page is present (or was at the time the endptr was
1819 : : * read; must re-verify later). Calculate pointer to source data and
1820 : : * determine how much data to read from this page.
1821 : : */
1822 : 26455 : page = XLogCtl->pages + idx * (Size) XLOG_BLCKSZ;
1823 : 26455 : psrc = page + offset;
1824 : 26455 : npagebytes = Min(nbytes, XLOG_BLCKSZ - offset);
1825 : :
1826 : : /*
1827 : : * Ensure that the data copy and the first verification step are not
1828 : : * reordered.
1829 : : */
1830 : 26455 : pg_read_barrier();
1831 : :
1832 : : /* data copy */
1833 : 26455 : memcpy(pdst, psrc, npagebytes);
1834 : :
1835 : : /*
1836 : : * Ensure that the data copy and the second verification step are not
1837 : : * reordered.
1838 : : */
1839 : 26455 : pg_read_barrier();
1840 : :
1841 : : /*
1842 : : * Second verification step: check that the page we read from wasn't
1843 : : * evicted while we were copying the data.
1844 : : */
1845 : 26455 : endptr = pg_atomic_read_u64(&XLogCtl->xlblocks[idx]);
1846 [ - + ]: 26455 : if (expectedEndPtr != endptr)
762 jdavis@postgresql.or 1847 :UBC 0 : break;
1848 : :
762 jdavis@postgresql.or 1849 :CBC 26455 : pdst += npagebytes;
1850 : 26455 : recptr += npagebytes;
1851 : 26455 : nbytes -= npagebytes;
1852 : : }
1853 : :
1854 [ - + ]: 103248 : Assert(pdst - dstbuf <= count);
1855 : :
1856 : 103248 : return pdst - dstbuf;
1857 : : }
1858 : :
1859 : : /*
1860 : : * Converts a "usable byte position" to XLogRecPtr. A usable byte position
1861 : : * is the position starting from the beginning of WAL, excluding all WAL
1862 : : * page headers.
1863 : : */
1864 : : static XLogRecPtr
4633 heikki.linnakangas@i 1865 : 32135707 : XLogBytePosToRecPtr(uint64 bytepos)
1866 : : {
1867 : : uint64 fullsegs;
1868 : : uint64 fullpages;
1869 : : uint64 bytesleft;
1870 : : uint32 seg_offset;
1871 : : XLogRecPtr result;
1872 : :
1873 : 32135707 : fullsegs = bytepos / UsableBytesInSegment;
1874 : 32135707 : bytesleft = bytepos % UsableBytesInSegment;
1875 : :
1876 [ + + ]: 32135707 : if (bytesleft < XLOG_BLCKSZ - SizeOfXLogLongPHD)
1877 : : {
1878 : : /* fits on first page of segment */
1879 : 60078 : seg_offset = bytesleft + SizeOfXLogLongPHD;
1880 : : }
1881 : : else
1882 : : {
1883 : : /* account for the first page on segment with long header */
1884 : 32075629 : seg_offset = XLOG_BLCKSZ;
1885 : 32075629 : bytesleft -= XLOG_BLCKSZ - SizeOfXLogLongPHD;
1886 : :
1887 : 32075629 : fullpages = bytesleft / UsableBytesInPage;
1888 : 32075629 : bytesleft = bytesleft % UsableBytesInPage;
1889 : :
1890 : 32075629 : seg_offset += fullpages * XLOG_BLCKSZ + bytesleft + SizeOfXLogShortPHD;
1891 : : }
1892 : :
2806 alvherre@alvh.no-ip. 1893 : 32135707 : XLogSegNoOffsetToRecPtr(fullsegs, seg_offset, wal_segment_size, result);
1894 : :
4633 heikki.linnakangas@i 1895 : 32135707 : return result;
1896 : : }
1897 : :
1898 : : /*
1899 : : * Like XLogBytePosToRecPtr, but if the position is at a page boundary,
1900 : : * returns a pointer to the beginning of the page (ie. before page header),
1901 : : * not to where the first xlog record on that page would go to. This is used
1902 : : * when converting a pointer to the end of a record.
1903 : : */
1904 : : static XLogRecPtr
1905 : 16559147 : XLogBytePosToEndRecPtr(uint64 bytepos)
1906 : : {
1907 : : uint64 fullsegs;
1908 : : uint64 fullpages;
1909 : : uint64 bytesleft;
1910 : : uint32 seg_offset;
1911 : : XLogRecPtr result;
1912 : :
1913 : 16559147 : fullsegs = bytepos / UsableBytesInSegment;
1914 : 16559147 : bytesleft = bytepos % UsableBytesInSegment;
1915 : :
1916 [ + + ]: 16559147 : if (bytesleft < XLOG_BLCKSZ - SizeOfXLogLongPHD)
1917 : : {
1918 : : /* fits on first page of segment */
1919 [ + + ]: 102231 : if (bytesleft == 0)
1920 : 70793 : seg_offset = 0;
1921 : : else
1922 : 31438 : seg_offset = bytesleft + SizeOfXLogLongPHD;
1923 : : }
1924 : : else
1925 : : {
1926 : : /* account for the first page on segment with long header */
1927 : 16456916 : seg_offset = XLOG_BLCKSZ;
1928 : 16456916 : bytesleft -= XLOG_BLCKSZ - SizeOfXLogLongPHD;
1929 : :
1930 : 16456916 : fullpages = bytesleft / UsableBytesInPage;
1931 : 16456916 : bytesleft = bytesleft % UsableBytesInPage;
1932 : :
1933 [ + + ]: 16456916 : if (bytesleft == 0)
1934 : 15880 : seg_offset += fullpages * XLOG_BLCKSZ + bytesleft;
1935 : : else
1936 : 16441036 : seg_offset += fullpages * XLOG_BLCKSZ + bytesleft + SizeOfXLogShortPHD;
1937 : : }
1938 : :
2806 alvherre@alvh.no-ip. 1939 : 16559147 : XLogSegNoOffsetToRecPtr(fullsegs, seg_offset, wal_segment_size, result);
1940 : :
4633 heikki.linnakangas@i 1941 : 16559147 : return result;
1942 : : }
1943 : :
1944 : : /*
1945 : : * Convert an XLogRecPtr to a "usable byte position".
1946 : : */
1947 : : static uint64
1948 : 48192854 : XLogRecPtrToBytePos(XLogRecPtr ptr)
1949 : : {
1950 : : uint64 fullsegs;
1951 : : uint32 fullpages;
1952 : : uint32 offset;
1953 : : uint64 result;
1954 : :
3099 andres@anarazel.de 1955 : 48192854 : XLByteToSeg(ptr, fullsegs, wal_segment_size);
1956 : :
1957 : 48192854 : fullpages = (XLogSegmentOffset(ptr, wal_segment_size)) / XLOG_BLCKSZ;
4633 heikki.linnakangas@i 1958 : 48192854 : offset = ptr % XLOG_BLCKSZ;
1959 : :
1960 [ + + ]: 48192854 : if (fullpages == 0)
1961 : : {
1962 : 90942 : result = fullsegs * UsableBytesInSegment;
1963 [ + + ]: 90942 : if (offset > 0)
1964 : : {
1965 [ - + ]: 89398 : Assert(offset >= SizeOfXLogLongPHD);
1966 : 89398 : result += offset - SizeOfXLogLongPHD;
1967 : : }
1968 : : }
1969 : : else
1970 : : {
1971 : 48101912 : result = fullsegs * UsableBytesInSegment +
4331 bruce@momjian.us 1972 : 48101912 : (XLOG_BLCKSZ - SizeOfXLogLongPHD) + /* account for first page */
3189 tgl@sss.pgh.pa.us 1973 : 48101912 : (fullpages - 1) * UsableBytesInPage; /* full pages */
4633 heikki.linnakangas@i 1974 [ + + ]: 48101912 : if (offset > 0)
1975 : : {
1976 [ - + ]: 48086322 : Assert(offset >= SizeOfXLogShortPHD);
1977 : 48086322 : result += offset - SizeOfXLogShortPHD;
1978 : : }
1979 : : }
1980 : :
1981 : 48192854 : return result;
1982 : : }
1983 : :
1984 : : /*
1985 : : * Initialize XLOG buffers, writing out old buffers if they still contain
1986 : : * unwritten data, upto the page containing 'upto'. Or if 'opportunistic' is
1987 : : * true, initialize as many pages as we can without having to write out
1988 : : * unwritten data. Any new pages are initialized to zeros, with pages headers
1989 : : * initialized properly.
1990 : : */
1991 : : static void
1591 rhaas@postgresql.org 1992 : 2508660 : AdvanceXLInsertBuffer(XLogRecPtr upto, TimeLineID tli, bool opportunistic)
1993 : : {
1994 : : int nextidx;
1995 : : XLogRecPtr OldPageRqstPtr;
1996 : : XLogwrtRqst WriteRqst;
4633 heikki.linnakangas@i 1997 : 2508660 : XLogRecPtr NewPageEndPtr = InvalidXLogRecPtr;
1998 : : XLogRecPtr NewPageBeginPtr;
1999 : : XLogPageHeader NewPage;
1272 tgl@sss.pgh.pa.us 2000 : 2508660 : int npages pg_attribute_unused() = 0;
2001 : :
205 akorotkov@postgresql 2002 : 2508660 : LWLockAcquire(WALBufMappingLock, LW_EXCLUSIVE);
2003 : :
2004 : : /*
2005 : : * Now that we have the lock, check if someone initialized the page
2006 : : * already.
2007 : : */
2008 [ + + + + ]: 7373959 : while (upto >= XLogCtl->InitializedUpTo || opportunistic)
2009 : : {
2010 : 4868930 : nextidx = XLogRecPtrToBufIdx(XLogCtl->InitializedUpTo);
2011 : :
2012 : : /*
2013 : : * Get ending-offset of the buffer page we need to replace (this may
2014 : : * be zero if the buffer hasn't been used yet). Fall through if it's
2015 : : * already written out.
2016 : : */
2017 : 4868930 : OldPageRqstPtr = pg_atomic_read_u64(&XLogCtl->xlblocks[nextidx]);
2018 [ + + ]: 4868930 : if (LogwrtResult.Write < OldPageRqstPtr)
2019 : : {
2020 : : /*
2021 : : * Nope, got work to do. If we just want to pre-initialize as much
2022 : : * as we can without flushing, give up now.
2023 : : */
2024 [ + + ]: 2243596 : if (opportunistic)
2025 : 3631 : break;
2026 : :
2027 : : /* Advance shared memory write request position */
4192 andres@anarazel.de 2028 [ + + ]: 2239965 : SpinLockAcquire(&XLogCtl->info_lck);
2029 [ + + ]: 2239965 : if (XLogCtl->LogwrtRqst.Write < OldPageRqstPtr)
2030 : 693026 : XLogCtl->LogwrtRqst.Write = OldPageRqstPtr;
2031 : 2239965 : SpinLockRelease(&XLogCtl->info_lck);
2032 : :
2033 : : /*
2034 : : * Acquire an up-to-date LogwrtResult value and see if we still
2035 : : * need to write it or if someone else already did.
2036 : : */
709 alvherre@alvh.no-ip. 2037 : 2239965 : RefreshXLogWriteResult(LogwrtResult);
4633 heikki.linnakangas@i 2038 [ + + ]: 2239965 : if (LogwrtResult.Write < OldPageRqstPtr)
2039 : : {
2040 : : /*
2041 : : * Must acquire write lock. Release WALBufMappingLock first,
2042 : : * to make sure that all insertions that we need to wait for
2043 : : * can finish (up to this same position). Otherwise we risk
2044 : : * deadlock.
2045 : : */
205 akorotkov@postgresql 2046 : 2225034 : LWLockRelease(WALBufMappingLock);
2047 : :
4633 heikki.linnakangas@i 2048 : 2225034 : WaitXLogInsertionsToFinish(OldPageRqstPtr);
2049 : :
2050 : 2225034 : LWLockAcquire(WALWriteLock, LW_EXCLUSIVE);
2051 : :
711 alvherre@alvh.no-ip. 2052 : 2225034 : RefreshXLogWriteResult(LogwrtResult);
4633 heikki.linnakangas@i 2053 [ + + ]: 2225034 : if (LogwrtResult.Write >= OldPageRqstPtr)
2054 : : {
2055 : : /* OK, someone wrote it already */
2056 : 139845 : LWLockRelease(WALWriteLock);
2057 : : }
2058 : : else
2059 : : {
2060 : : /* Have to write it ourselves */
2061 : : TRACE_POSTGRESQL_WAL_BUFFER_WRITE_DIRTY_START();
2062 : 2085189 : WriteRqst.Write = OldPageRqstPtr;
45 alvherre@kurilemu.de 2063 :GNC 2085189 : WriteRqst.Flush = InvalidXLogRecPtr;
1591 rhaas@postgresql.org 2064 :CBC 2085189 : XLogWrite(WriteRqst, tli, false);
4633 heikki.linnakangas@i 2065 : 2085189 : LWLockRelease(WALWriteLock);
391 michael@paquier.xyz 2066 : 2085189 : pgWalUsage.wal_buffers_full++;
2067 : : TRACE_POSTGRESQL_WAL_BUFFER_WRITE_DIRTY_DONE();
2068 : :
2069 : : /*
2070 : : * Required for the flush of pending stats WAL data, per
2071 : : * update of pgWalUsage.
2072 : : */
230 2073 : 2085189 : pgstat_report_fixed = true;
2074 : : }
2075 : : /* Re-acquire WALBufMappingLock and retry */
205 akorotkov@postgresql 2076 : 2225034 : LWLockAcquire(WALBufMappingLock, LW_EXCLUSIVE);
2077 : 2225034 : continue;
2078 : : }
2079 : : }
2080 : :
2081 : : /*
2082 : : * Now the next buffer slot is free and we can set it up to be the
2083 : : * next output page.
2084 : : */
2085 : 2640265 : NewPageBeginPtr = XLogCtl->InitializedUpTo;
4633 heikki.linnakangas@i 2086 : 2640265 : NewPageEndPtr = NewPageBeginPtr + XLOG_BLCKSZ;
2087 : :
205 akorotkov@postgresql 2088 [ - + ]: 2640265 : Assert(XLogRecPtrToBufIdx(NewPageBeginPtr) == nextidx);
2089 : :
4633 heikki.linnakangas@i 2090 : 2640265 : NewPage = (XLogPageHeader) (XLogCtl->pages + nextidx * (Size) XLOG_BLCKSZ);
2091 : :
2092 : : /*
2093 : : * Mark the xlblock with InvalidXLogRecPtr and issue a write barrier
2094 : : * before initializing. Otherwise, the old page may be partially
2095 : : * zeroed but look valid.
2096 : : */
817 jdavis@postgresql.or 2097 : 2640265 : pg_atomic_write_u64(&XLogCtl->xlblocks[nextidx], InvalidXLogRecPtr);
2098 : 2640265 : pg_write_barrier();
2099 : :
2100 : : /*
2101 : : * Be sure to re-zero the buffer so that bytes beyond what we've
2102 : : * written will look like zeroes and not valid XLOG records...
2103 : : */
396 peter@eisentraut.org 2104 [ + - + - : 2640265 : MemSet(NewPage, 0, XLOG_BLCKSZ);
+ - - + -
- ]
2105 : :
2106 : : /*
2107 : : * Fill the new page's header
2108 : : */
3949 bruce@momjian.us 2109 : 2640265 : NewPage->xlp_magic = XLOG_PAGE_MAGIC;
2110 : :
2111 : : /* NewPage->xlp_info = 0; */ /* done by memset */
1591 rhaas@postgresql.org 2112 : 2640265 : NewPage->xlp_tli = tli;
3949 bruce@momjian.us 2113 : 2640265 : NewPage->xlp_pageaddr = NewPageBeginPtr;
2114 : :
2115 : : /* NewPage->xlp_rem_len = 0; */ /* done by memset */
2116 : :
2117 : : /*
2118 : : * If first page of an XLOG segment file, make it a long header.
2119 : : */
3099 andres@anarazel.de 2120 [ + + ]: 2640265 : if ((XLogSegmentOffset(NewPage->xlp_pageaddr, wal_segment_size)) == 0)
2121 : : {
4633 heikki.linnakangas@i 2122 : 1861 : XLogLongPageHeader NewLongPage = (XLogLongPageHeader) NewPage;
2123 : :
2124 : 1861 : NewLongPage->xlp_sysid = ControlFile->system_identifier;
3099 andres@anarazel.de 2125 : 1861 : NewLongPage->xlp_seg_size = wal_segment_size;
4633 heikki.linnakangas@i 2126 : 1861 : NewLongPage->xlp_xlog_blcksz = XLOG_BLCKSZ;
3949 bruce@momjian.us 2127 : 1861 : NewPage->xlp_info |= XLP_LONG_HEADER;
2128 : : }
2129 : :
2130 : : /*
2131 : : * Make sure the initialization of the page becomes visible to others
2132 : : * before the xlblocks update. GetXLogBuffer() reads xlblocks without
2133 : : * holding a lock.
2134 : : */
4633 heikki.linnakangas@i 2135 : 2640265 : pg_write_barrier();
2136 : :
817 jdavis@postgresql.or 2137 : 2640265 : pg_atomic_write_u64(&XLogCtl->xlblocks[nextidx], NewPageEndPtr);
205 akorotkov@postgresql 2138 : 2640265 : XLogCtl->InitializedUpTo = NewPageEndPtr;
2139 : :
4633 heikki.linnakangas@i 2140 : 2640265 : npages++;
2141 : : }
205 akorotkov@postgresql 2142 : 2508660 : LWLockRelease(WALBufMappingLock);
2143 : :
2144 : : #ifdef WAL_DEBUG
2145 : : if (XLOG_DEBUG && npages > 0)
2146 : : {
2147 : : elog(DEBUG1, "initialized %d pages, up to %X/%08X",
2148 : : npages, LSN_FORMAT_ARGS(NewPageEndPtr));
2149 : : }
2150 : : #endif
9666 vadim4o@yahoo.com 2151 : 2508660 : }
2152 : :
2153 : : /*
2154 : : * Calculate CheckPointSegments based on max_wal_size_mb and
2155 : : * checkpoint_completion_target.
2156 : : */
2157 : : static void
4038 heikki.linnakangas@i 2158 : 8318 : CalculateCheckpointSegments(void)
2159 : : {
2160 : : double target;
2161 : :
2162 : : /*-------
2163 : : * Calculate the distance at which to trigger a checkpoint, to avoid
2164 : : * exceeding max_wal_size_mb. This is based on two assumptions:
2165 : : *
2166 : : * a) we keep WAL for only one checkpoint cycle (prior to PG11 we kept
2167 : : * WAL for two checkpoint cycles to allow us to recover from the
2168 : : * secondary checkpoint if the first checkpoint failed, though we
2169 : : * only did this on the primary anyway, not on standby. Keeping just
2170 : : * one checkpoint simplifies processing and reduces disk space in
2171 : : * many smaller databases.)
2172 : : * b) during checkpoint, we consume checkpoint_completion_target *
2173 : : * number of segments consumed between checkpoints.
2174 : : *-------
2175 : : */
3099 andres@anarazel.de 2176 : 8318 : target = (double) ConvertToXSegs(max_wal_size_mb, wal_segment_size) /
3050 simon@2ndQuadrant.co 2177 : 8318 : (1.0 + CheckPointCompletionTarget);
2178 : :
2179 : : /* round down */
4038 heikki.linnakangas@i 2180 : 8318 : CheckPointSegments = (int) target;
2181 : :
2182 [ + + ]: 8318 : if (CheckPointSegments < 1)
2183 : 10 : CheckPointSegments = 1;
2184 : 8318 : }
2185 : :
2186 : : void
2187 : 6078 : assign_max_wal_size(int newval, void *extra)
2188 : : {
3267 simon@2ndQuadrant.co 2189 : 6078 : max_wal_size_mb = newval;
4038 heikki.linnakangas@i 2190 : 6078 : CalculateCheckpointSegments();
2191 : 6078 : }
2192 : :
2193 : : void
2194 : 1184 : assign_checkpoint_completion_target(double newval, void *extra)
2195 : : {
2196 : 1184 : CheckPointCompletionTarget = newval;
2197 : 1184 : CalculateCheckpointSegments();
2198 : 1184 : }
2199 : :
2200 : : bool
930 peter@eisentraut.org 2201 : 2292 : check_wal_segment_size(int *newval, void **extra, GucSource source)
2202 : : {
2203 [ + - + - : 2292 : if (!IsValidWalSegSize(*newval))
+ - - + ]
2204 : : {
930 peter@eisentraut.org 2205 :UBC 0 : GUC_check_errdetail("The WAL segment size must be a power of two between 1 MB and 1 GB.");
2206 : 0 : return false;
2207 : : }
2208 : :
930 peter@eisentraut.org 2209 :CBC 2292 : return true;
2210 : : }
2211 : :
2212 : : /*
2213 : : * At a checkpoint, how many WAL segments to recycle as preallocated future
2214 : : * XLOG segments? Returns the highest segment that should be preallocated.
2215 : : */
2216 : : static XLogSegNo
2279 michael@paquier.xyz 2217 : 1802 : XLOGfileslop(XLogRecPtr lastredoptr)
2218 : : {
2219 : : XLogSegNo minSegNo;
2220 : : XLogSegNo maxSegNo;
2221 : : double distance;
2222 : : XLogSegNo recycleSegNo;
2223 : :
2224 : : /*
2225 : : * Calculate the segment numbers that min_wal_size_mb and max_wal_size_mb
2226 : : * correspond to. Always recycle enough segments to meet the minimum, and
2227 : : * remove enough segments to stay below the maximum.
2228 : : */
2229 : 1802 : minSegNo = lastredoptr / wal_segment_size +
3099 andres@anarazel.de 2230 : 1802 : ConvertToXSegs(min_wal_size_mb, wal_segment_size) - 1;
2279 michael@paquier.xyz 2231 : 1802 : maxSegNo = lastredoptr / wal_segment_size +
3099 andres@anarazel.de 2232 : 1802 : ConvertToXSegs(max_wal_size_mb, wal_segment_size) - 1;
2233 : :
2234 : : /*
2235 : : * Between those limits, recycle enough segments to get us through to the
2236 : : * estimated end of next checkpoint.
2237 : : *
2238 : : * To estimate where the next checkpoint will finish, assume that the
2239 : : * system runs steadily consuming CheckPointDistanceEstimate bytes between
2240 : : * every checkpoint.
2241 : : */
3050 simon@2ndQuadrant.co 2242 : 1802 : distance = (1.0 + CheckPointCompletionTarget) * CheckPointDistanceEstimate;
2243 : : /* add 10% for good measure. */
4038 heikki.linnakangas@i 2244 : 1802 : distance *= 1.10;
2245 : :
2279 michael@paquier.xyz 2246 : 1802 : recycleSegNo = (XLogSegNo) ceil(((double) lastredoptr + distance) /
2247 : : wal_segment_size);
2248 : :
4038 heikki.linnakangas@i 2249 [ + + ]: 1802 : if (recycleSegNo < minSegNo)
2250 : 1271 : recycleSegNo = minSegNo;
2251 [ + + ]: 1802 : if (recycleSegNo > maxSegNo)
2252 : 404 : recycleSegNo = maxSegNo;
2253 : :
2254 : 1802 : return recycleSegNo;
2255 : : }
2256 : :
2257 : : /*
2258 : : * Check whether we've consumed enough xlog space that a checkpoint is needed.
2259 : : *
2260 : : * new_segno indicates a log file that has just been filled up (or read
2261 : : * during recovery). We measure the distance from RedoRecPtr to new_segno
2262 : : * and see if that exceeds CheckPointSegments.
2263 : : *
2264 : : * Note: it is caller's responsibility that RedoRecPtr is up-to-date.
2265 : : */
2266 : : bool
5012 2267 : 4803 : XLogCheckpointNeeded(XLogSegNo new_segno)
2268 : : {
2269 : : XLogSegNo old_segno;
2270 : :
3099 andres@anarazel.de 2271 : 4803 : XLByteToSeg(RedoRecPtr, old_segno, wal_segment_size);
2272 : :
5012 heikki.linnakangas@i 2273 [ + + ]: 4803 : if (new_segno >= old_segno + (uint64) (CheckPointSegments - 1))
6729 tgl@sss.pgh.pa.us 2274 : 2956 : return true;
2275 : 1847 : return false;
2276 : : }
2277 : :
2278 : : /*
2279 : : * Write and/or fsync the log at least as far as WriteRqst indicates.
2280 : : *
2281 : : * If flexible == true, we don't have to write as far as WriteRqst, but
2282 : : * may stop at any convenient boundary (such as a cache or logfile boundary).
2283 : : * This option allows us to avoid uselessly issuing multiple writes when a
2284 : : * single one would do.
2285 : : *
2286 : : * Must be called with WALWriteLock held. WaitXLogInsertionsToFinish(WriteRqst)
2287 : : * must be called before grabbing the lock, to make sure the data is ready to
2288 : : * write.
2289 : : */
2290 : : static void
1591 rhaas@postgresql.org 2291 : 2217107 : XLogWrite(XLogwrtRqst WriteRqst, TimeLineID tli, bool flexible)
2292 : : {
2293 : : bool ispartialpage;
2294 : : bool last_iteration;
2295 : : bool finishing_seg;
2296 : : int curridx;
2297 : : int npages;
2298 : : int startidx;
2299 : : uint32 startoffset;
2300 : :
2301 : : /* We should always be inside a critical section here */
7639 tgl@sss.pgh.pa.us 2302 [ - + ]: 2217107 : Assert(CritSectionCount > 0);
2303 : :
2304 : : /*
2305 : : * Update local LogwrtResult (caller probably did this already, but...)
2306 : : */
711 alvherre@alvh.no-ip. 2307 : 2217107 : RefreshXLogWriteResult(LogwrtResult);
2308 : :
2309 : : /*
2310 : : * Since successive pages in the xlog cache are consecutively allocated,
2311 : : * we can usually gather multiple pages together and issue just one
2312 : : * write() call. npages is the number of pages we have determined can be
2313 : : * written together; startidx is the cache block index of the first one,
2314 : : * and startoffset is the file offset at which it should go. The latter
2315 : : * two variables are only valid when npages > 0, but we must initialize
2316 : : * all of them to keep the compiler quiet.
2317 : : */
7510 tgl@sss.pgh.pa.us 2318 : 2217107 : npages = 0;
2319 : 2217107 : startidx = 0;
2320 : 2217107 : startoffset = 0;
2321 : :
2322 : : /*
2323 : : * Within the loop, curridx is the cache block index of the page to
2324 : : * consider writing. Begin at the buffer containing the next unwritten
2325 : : * page, or last partially written page.
2326 : : */
4624 heikki.linnakangas@i 2327 : 2217107 : curridx = XLogRecPtrToBufIdx(LogwrtResult.Write);
2328 : :
4825 alvherre@alvh.no-ip. 2329 [ + + ]: 4796500 : while (LogwrtResult.Write < WriteRqst.Write)
2330 : : {
2331 : : /*
2332 : : * Make sure we're not ahead of the insert process. This could happen
2333 : : * if we're passed a bogus WriteRqst.Write that is past the end of the
2334 : : * last page that's been initialized by AdvanceXLInsertBuffer.
2335 : : */
817 jdavis@postgresql.or 2336 : 2705405 : XLogRecPtr EndPtr = pg_atomic_read_u64(&XLogCtl->xlblocks[curridx]);
2337 : :
4633 heikki.linnakangas@i 2338 [ - + ]: 2705405 : if (LogwrtResult.Write >= EndPtr)
251 alvherre@kurilemu.de 2339 [ # # ]:UNC 0 : elog(PANIC, "xlog write request %X/%08X is past end of log %X/%08X",
2340 : : LSN_FORMAT_ARGS(LogwrtResult.Write),
2341 : : LSN_FORMAT_ARGS(EndPtr));
2342 : :
2343 : : /* Advance LogwrtResult.Write to end of current buffer page */
4633 heikki.linnakangas@i 2344 :CBC 2705405 : LogwrtResult.Write = EndPtr;
4825 alvherre@alvh.no-ip. 2345 : 2705405 : ispartialpage = WriteRqst.Write < LogwrtResult.Write;
2346 : :
3099 andres@anarazel.de 2347 [ + + ]: 2705405 : if (!XLByteInPrevSeg(LogwrtResult.Write, openLogSegNo,
2348 : : wal_segment_size))
2349 : : {
2350 : : /*
2351 : : * Switch to new logfile segment. We cannot have any pending
2352 : : * pages here (since we dump what we have at segment end).
2353 : : */
7510 tgl@sss.pgh.pa.us 2354 [ - + ]: 13769 : Assert(npages == 0);
9133 2355 [ + + ]: 13769 : if (openLogFile >= 0)
7213 bruce@momjian.us 2356 : 6395 : XLogFileClose();
3099 andres@anarazel.de 2357 : 13769 : XLByteToPrevSeg(LogwrtResult.Write, openLogSegNo,
2358 : : wal_segment_size);
1591 rhaas@postgresql.org 2359 : 13769 : openLogTLI = tli;
2360 : :
2361 : : /* create/use new log file */
2362 : 13769 : openLogFile = XLogFileInit(openLogSegNo, tli);
2211 tgl@sss.pgh.pa.us 2363 : 13769 : ReserveExternalFD();
2364 : : }
2365 : :
2366 : : /* Make sure we have the current logfile open */
9133 2367 [ - + ]: 2705405 : if (openLogFile < 0)
2368 : : {
3099 andres@anarazel.de 2369 :UBC 0 : XLByteToPrevSeg(LogwrtResult.Write, openLogSegNo,
2370 : : wal_segment_size);
1591 rhaas@postgresql.org 2371 : 0 : openLogTLI = tli;
2372 : 0 : openLogFile = XLogFileOpen(openLogSegNo, tli);
2211 tgl@sss.pgh.pa.us 2373 : 0 : ReserveExternalFD();
2374 : : }
2375 : :
2376 : : /* Add current page to the set of pending pages-to-dump */
7510 tgl@sss.pgh.pa.us 2377 [ + + ]:CBC 2705405 : if (npages == 0)
2378 : : {
2379 : : /* first of group */
2380 : 2229576 : startidx = curridx;
3099 andres@anarazel.de 2381 : 2229576 : startoffset = XLogSegmentOffset(LogwrtResult.Write - XLOG_BLCKSZ,
2382 : : wal_segment_size);
2383 : : }
7510 tgl@sss.pgh.pa.us 2384 : 2705405 : npages++;
2385 : :
2386 : : /*
2387 : : * Dump the set if this will be the last loop iteration, or if we are
2388 : : * at the last page of the cache area (since the next page won't be
2389 : : * contiguous in memory), or if we are at the end of the logfile
2390 : : * segment.
2391 : : */
4825 alvherre@alvh.no-ip. 2392 : 2705405 : last_iteration = WriteRqst.Write <= LogwrtResult.Write;
2393 : :
7510 tgl@sss.pgh.pa.us 2394 [ + + ]: 5287519 : finishing_seg = !ispartialpage &&
3099 andres@anarazel.de 2395 [ + + ]: 2582114 : (startoffset + npages * XLOG_BLCKSZ) >= wal_segment_size;
2396 : :
7161 tgl@sss.pgh.pa.us 2397 [ + + ]: 2705405 : if (last_iteration ||
7510 2398 [ + + - + ]: 490980 : curridx == XLogCtl->XLogCacheBlck ||
2399 : : finishing_seg)
2400 : : {
2401 : : char *from;
2402 : : Size nbytes;
2403 : : Size nleft;
2404 : : ssize_t written;
2405 : : instr_time start;
2406 : :
2407 : : /* OK to write the page(s) */
7286 2408 : 2229576 : from = XLogCtl->pages + startidx * (Size) XLOG_BLCKSZ;
2409 : 2229576 : nbytes = npages * (Size) XLOG_BLCKSZ;
4640 heikki.linnakangas@i 2410 : 2229576 : nleft = nbytes;
2411 : : do
2412 : : {
2413 : 2229576 : errno = 0;
2414 : :
2415 : : /*
2416 : : * Measure I/O timing to write WAL data, for pg_stat_io.
2417 : : */
382 michael@paquier.xyz 2418 : 2229576 : start = pgstat_prepare_io_time(track_wal_io_timing);
2419 : :
3284 rhaas@postgresql.org 2420 : 2229576 : pgstat_report_wait_start(WAIT_EVENT_WAL_WRITE);
1263 tmunro@postgresql.or 2421 : 2229576 : written = pg_pwrite(openLogFile, from, nleft, startoffset);
3284 rhaas@postgresql.org 2422 : 2229576 : pgstat_report_wait_end();
2423 : :
404 michael@paquier.xyz 2424 : 2229576 : pgstat_count_io_op_time(IOOBJECT_WAL, IOCONTEXT_NORMAL,
2425 : : IOOP_WRITE, start, 1, written);
2426 : :
4640 heikki.linnakangas@i 2427 [ - + ]: 2229576 : if (written <= 0)
2428 : : {
2429 : : char xlogfname[MAXFNAMELEN];
2430 : : int save_errno;
2431 : :
4640 heikki.linnakangas@i 2432 [ # # ]:UBC 0 : if (errno == EINTR)
2433 : 0 : continue;
2434 : :
2294 michael@paquier.xyz 2435 : 0 : save_errno = errno;
1591 rhaas@postgresql.org 2436 : 0 : XLogFileName(xlogfname, tli, openLogSegNo,
2437 : : wal_segment_size);
2294 michael@paquier.xyz 2438 : 0 : errno = save_errno;
4640 heikki.linnakangas@i 2439 [ # # ]: 0 : ereport(PANIC,
2440 : : (errcode_for_file_access(),
2441 : : errmsg("could not write to log file \"%s\" at offset %u, length %zu: %m",
2442 : : xlogfname, startoffset, nleft)));
2443 : : }
4640 heikki.linnakangas@i 2444 :CBC 2229576 : nleft -= written;
2445 : 2229576 : from += written;
2685 tmunro@postgresql.or 2446 : 2229576 : startoffset += written;
4640 heikki.linnakangas@i 2447 [ - + ]: 2229576 : } while (nleft > 0);
2448 : :
7510 tgl@sss.pgh.pa.us 2449 : 2229576 : npages = 0;
2450 : :
2451 : : /*
2452 : : * If we just wrote the whole last page of a logfile segment,
2453 : : * fsync the segment immediately. This avoids having to go back
2454 : : * and re-open prior segments when an fsync request comes along
2455 : : * later. Doing it here ensures that one and only one backend will
2456 : : * perform this fsync.
2457 : : *
2458 : : * This is also the right place to notify the Archiver that the
2459 : : * segment is ready to copy to archival storage, and to update the
2460 : : * timer for archive_timeout, and to signal for a checkpoint if
2461 : : * too many logfile segments have been used since the last
2462 : : * checkpoint.
2463 : : */
4633 heikki.linnakangas@i 2464 [ + + ]: 2229576 : if (finishing_seg)
2465 : : {
1591 rhaas@postgresql.org 2466 : 1972 : issue_xlog_fsync(openLogFile, openLogSegNo, tli);
2467 : :
2468 : : /* signal that we need to wakeup walsenders later */
5004 2469 : 1972 : WalSndWakeupRequest();
2470 : :
3189 tgl@sss.pgh.pa.us 2471 : 1972 : LogwrtResult.Flush = LogwrtResult.Write; /* end of page */
2472 : :
7510 2473 [ + + - + : 1972 : if (XLogArchivingActive())
+ + ]
1591 rhaas@postgresql.org 2474 : 409 : XLogArchiveNotifySeg(openLogSegNo, tli);
2475 : :
4624 heikki.linnakangas@i 2476 : 1972 : XLogCtl->lastSegSwitchTime = (pg_time_t) time(NULL);
3370 andres@anarazel.de 2477 : 1972 : XLogCtl->lastSegSwitchLSN = LogwrtResult.Flush;
2478 : :
2479 : : /*
2480 : : * Request a checkpoint if we've consumed too much xlog since
2481 : : * the last one. For speed, we first check using the local
2482 : : * copy of RedoRecPtr, which might be out of date; if it looks
2483 : : * like a checkpoint is needed, forcibly update RedoRecPtr and
2484 : : * recheck.
2485 : : */
5012 heikki.linnakangas@i 2486 [ + + + + ]: 1972 : if (IsUnderPostmaster && XLogCheckpointNeeded(openLogSegNo))
2487 : : {
6729 tgl@sss.pgh.pa.us 2488 : 260 : (void) GetRedoRecPtr();
5012 heikki.linnakangas@i 2489 [ + + ]: 260 : if (XLogCheckpointNeeded(openLogSegNo))
6833 tgl@sss.pgh.pa.us 2490 : 210 : RequestCheckpoint(CHECKPOINT_CAUSE_XLOG);
2491 : : }
2492 : : }
2493 : : }
2494 : :
9133 2495 [ + + ]: 2705405 : if (ispartialpage)
2496 : : {
2497 : : /* Only asked to write a partial page */
2498 : 123291 : LogwrtResult.Write = WriteRqst.Write;
2499 : 123291 : break;
2500 : : }
7510 2501 [ + + ]: 2582114 : curridx = NextBufIdx(curridx);
2502 : :
2503 : : /* If flexible, break out of loop as soon as we wrote something */
2504 [ + + + + ]: 2582114 : if (flexible && npages == 0)
2505 : 2721 : break;
2506 : : }
2507 : :
2508 [ - + ]: 2217107 : Assert(npages == 0);
2509 : :
2510 : : /*
2511 : : * If asked to flush, do so
2512 : : */
4825 alvherre@alvh.no-ip. 2513 [ + + ]: 2217107 : if (LogwrtResult.Flush < WriteRqst.Flush &&
2514 [ + + ]: 131147 : LogwrtResult.Flush < LogwrtResult.Write)
2515 : : {
2516 : : /*
2517 : : * Could get here without iterating above loop, in which case we might
2518 : : * have no open file or the wrong one. However, we do not need to
2519 : : * fsync more than one file.
2520 : : */
884 nathan@postgresql.or 2521 [ + - ]: 131053 : if (wal_sync_method != WAL_SYNC_METHOD_OPEN &&
2522 [ + - ]: 131053 : wal_sync_method != WAL_SYNC_METHOD_OPEN_DSYNC)
2523 : : {
9130 tgl@sss.pgh.pa.us 2524 [ + + ]: 131053 : if (openLogFile >= 0 &&
3099 andres@anarazel.de 2525 [ + + ]: 131030 : !XLByteInPrevSeg(LogwrtResult.Write, openLogSegNo,
2526 : : wal_segment_size))
7213 bruce@momjian.us 2527 : 154 : XLogFileClose();
9130 tgl@sss.pgh.pa.us 2528 [ + + ]: 131053 : if (openLogFile < 0)
2529 : : {
3099 andres@anarazel.de 2530 : 177 : XLByteToPrevSeg(LogwrtResult.Write, openLogSegNo,
2531 : : wal_segment_size);
1591 rhaas@postgresql.org 2532 : 177 : openLogTLI = tli;
2533 : 177 : openLogFile = XLogFileOpen(openLogSegNo, tli);
2211 tgl@sss.pgh.pa.us 2534 : 177 : ReserveExternalFD();
2535 : : }
2536 : :
1591 rhaas@postgresql.org 2537 : 131053 : issue_xlog_fsync(openLogFile, openLogSegNo, tli);
2538 : : }
2539 : :
2540 : : /* signal that we need to wakeup walsenders later */
5004 2541 : 131053 : WalSndWakeupRequest();
2542 : :
9133 tgl@sss.pgh.pa.us 2543 : 131053 : LogwrtResult.Flush = LogwrtResult.Write;
2544 : : }
2545 : :
2546 : : /*
2547 : : * Update shared-memory status
2548 : : *
2549 : : * We make sure that the shared 'request' values do not fall behind the
2550 : : * 'result' values. This is not absolutely essential, but it saves some
2551 : : * code in a couple of places.
2552 : : */
709 alvherre@alvh.no-ip. 2553 [ + + ]: 2217107 : SpinLockAcquire(&XLogCtl->info_lck);
2554 [ + + ]: 2217107 : if (XLogCtl->LogwrtRqst.Write < LogwrtResult.Write)
2555 : 114202 : XLogCtl->LogwrtRqst.Write = LogwrtResult.Write;
2556 [ + + ]: 2217107 : if (XLogCtl->LogwrtRqst.Flush < LogwrtResult.Flush)
2557 : 132627 : XLogCtl->LogwrtRqst.Flush = LogwrtResult.Flush;
2558 : 2217107 : SpinLockRelease(&XLogCtl->info_lck);
2559 : :
2560 : : /*
2561 : : * We write Write first, bar, then Flush. When reading, the opposite must
2562 : : * be done (with a matching barrier in between), so that we always see a
2563 : : * Flush value that trails behind the Write value seen.
2564 : : */
2565 : 2217107 : pg_atomic_write_u64(&XLogCtl->logWriteResult, LogwrtResult.Write);
2566 : 2217107 : pg_write_barrier();
2567 : 2217107 : pg_atomic_write_u64(&XLogCtl->logFlushResult, LogwrtResult.Flush);
2568 : :
2569 : : #ifdef USE_ASSERT_CHECKING
2570 : : {
2571 : : XLogRecPtr Flush;
2572 : : XLogRecPtr Write;
2573 : : XLogRecPtr Insert;
2574 : :
2575 : 2217107 : Flush = pg_atomic_read_u64(&XLogCtl->logFlushResult);
2576 : 2217107 : pg_read_barrier();
2577 : 2217107 : Write = pg_atomic_read_u64(&XLogCtl->logWriteResult);
707 2578 : 2217107 : pg_read_barrier();
2579 : 2217107 : Insert = pg_atomic_read_u64(&XLogCtl->logInsertResult);
2580 : :
2581 : : /* WAL written to disk is always ahead of WAL flushed */
709 2582 [ - + ]: 2217107 : Assert(Write >= Flush);
2583 : :
2584 : : /* WAL inserted to buffers is always ahead of WAL written */
707 2585 [ - + ]: 2217107 : Assert(Insert >= Write);
2586 : : }
2587 : : #endif
9133 tgl@sss.pgh.pa.us 2588 : 2217107 : }
2589 : :
2590 : : /*
2591 : : * Record the LSN for an asynchronous transaction commit/abort
2592 : : * and nudge the WALWriter if there is work for it to do.
2593 : : * (This should not be called for synchronous commits.)
2594 : : */
2595 : : void
5708 simon@2ndQuadrant.co 2596 : 31529 : XLogSetAsyncXactLSN(XLogRecPtr asyncXactLSN)
2597 : : {
5236 2598 : 31529 : XLogRecPtr WriteRqstPtr = asyncXactLSN;
2599 : : bool sleeping;
839 heikki.linnakangas@i 2600 : 31529 : bool wakeup = false;
2601 : : XLogRecPtr prevAsyncXactLSN;
2602 : :
4192 andres@anarazel.de 2603 [ + + ]: 31529 : SpinLockAcquire(&XLogCtl->info_lck);
2604 : 31529 : sleeping = XLogCtl->WalWriterSleeping;
839 heikki.linnakangas@i 2605 : 31529 : prevAsyncXactLSN = XLogCtl->asyncXactLSN;
4192 andres@anarazel.de 2606 [ + + ]: 31529 : if (XLogCtl->asyncXactLSN < asyncXactLSN)
2607 : 31031 : XLogCtl->asyncXactLSN = asyncXactLSN;
2608 : 31529 : SpinLockRelease(&XLogCtl->info_lck);
2609 : :
2610 : : /*
2611 : : * If somebody else already called this function with a more aggressive
2612 : : * LSN, they will have done what we needed (and perhaps more).
2613 : : */
839 heikki.linnakangas@i 2614 [ + + ]: 31529 : if (asyncXactLSN <= prevAsyncXactLSN)
2615 : 498 : return;
2616 : :
2617 : : /*
2618 : : * If the WALWriter is sleeping, kick it to make it come out of low-power
2619 : : * mode, so that this async commit will reach disk within the expected
2620 : : * amount of time. Otherwise, determine whether it has enough WAL
2621 : : * available to flush, the same way that XLogBackgroundFlush() does.
2622 : : */
2623 [ + + ]: 31031 : if (sleeping)
2624 : 16 : wakeup = true;
2625 : : else
2626 : : {
2627 : : int flushblocks;
2628 : :
709 alvherre@alvh.no-ip. 2629 : 31015 : RefreshXLogWriteResult(LogwrtResult);
2630 : :
839 heikki.linnakangas@i 2631 : 31015 : flushblocks =
2632 : 31015 : WriteRqstPtr / XLOG_BLCKSZ - LogwrtResult.Flush / XLOG_BLCKSZ;
2633 : :
2634 [ + - + + ]: 31015 : if (WalWriterFlushAfter == 0 || flushblocks >= WalWriterFlushAfter)
2635 : 4173 : wakeup = true;
2636 : : }
2637 : :
499 2638 [ + + ]: 31031 : if (wakeup)
2639 : : {
2640 : 4189 : volatile PROC_HDR *procglobal = ProcGlobal;
2641 : 4189 : ProcNumber walwriterProc = procglobal->walwriterProc;
2642 : :
2643 [ + + ]: 4189 : if (walwriterProc != INVALID_PROC_NUMBER)
2644 : 190 : SetLatch(&GetPGProcByNumber(walwriterProc)->procLatch);
2645 : : }
2646 : : }
2647 : :
2648 : : /*
2649 : : * Record the LSN up to which we can remove WAL because it's not required by
2650 : : * any replication slot.
2651 : : */
2652 : : void
4426 rhaas@postgresql.org 2653 : 40259 : XLogSetReplicationSlotMinimumLSN(XLogRecPtr lsn)
2654 : : {
4192 andres@anarazel.de 2655 [ + + ]: 40259 : SpinLockAcquire(&XLogCtl->info_lck);
2656 : 40259 : XLogCtl->replicationSlotMinLSN = lsn;
2657 : 40259 : SpinLockRelease(&XLogCtl->info_lck);
4426 rhaas@postgresql.org 2658 : 40259 : }
2659 : :
2660 : :
2661 : : /*
2662 : : * Return the oldest LSN we must retain to satisfy the needs of some
2663 : : * replication slot.
2664 : : */
2665 : : XLogRecPtr
2666 : 2405 : XLogGetReplicationSlotMinimumLSN(void)
2667 : : {
2668 : : XLogRecPtr retval;
2669 : :
4192 andres@anarazel.de 2670 [ + + ]: 2405 : SpinLockAcquire(&XLogCtl->info_lck);
2671 : 2405 : retval = XLogCtl->replicationSlotMinLSN;
2672 : 2405 : SpinLockRelease(&XLogCtl->info_lck);
2673 : :
4426 rhaas@postgresql.org 2674 : 2405 : return retval;
2675 : : }
2676 : :
2677 : : /*
2678 : : * Advance minRecoveryPoint in control file.
2679 : : *
2680 : : * If we crash during recovery, we must reach this point again before the
2681 : : * database is consistent.
2682 : : *
2683 : : * If 'force' is true, 'lsn' argument is ignored. Otherwise, minRecoveryPoint
2684 : : * is only updated if it's not already greater than or equal to 'lsn'.
2685 : : */
2686 : : static void
6234 heikki.linnakangas@i 2687 : 111007 : UpdateMinRecoveryPoint(XLogRecPtr lsn, bool force)
2688 : : {
2689 : : /* Quick check using our local copy of the variable */
1488 2690 [ + + + + : 111007 : if (!updateMinRecoveryPoint || (!force && lsn <= LocalMinRecoveryPoint))
+ + ]
6234 2691 : 103704 : return;
2692 : :
2693 : : /*
2694 : : * An invalid minRecoveryPoint means that we need to recover all the WAL,
2695 : : * i.e., we're doing crash recovery. We never modify the control file's
2696 : : * value in that case, so we can short-circuit future checks here too. The
2697 : : * local values of minRecoveryPoint and minRecoveryPointTLI should not be
2698 : : * updated until crash recovery finishes. We only do this for the startup
2699 : : * process as it should not update its own reference of minRecoveryPoint
2700 : : * until it has finished crash recovery to make sure that all WAL
2701 : : * available is replayed in this case. This also saves from extra locks
2702 : : * taken on the control file from the startup process.
2703 : : */
129 alvherre@kurilemu.de 2704 [ + + + + ]:GNC 7303 : if (!XLogRecPtrIsValid(LocalMinRecoveryPoint) && InRecovery)
2705 : : {
2810 michael@paquier.xyz 2706 :CBC 31 : updateMinRecoveryPoint = false;
2707 : 31 : return;
2708 : : }
2709 : :
6234 heikki.linnakangas@i 2710 : 7272 : LWLockAcquire(ControlFileLock, LW_EXCLUSIVE);
2711 : :
2712 : : /* update local copy */
1488 2713 : 7272 : LocalMinRecoveryPoint = ControlFile->minRecoveryPoint;
2714 : 7272 : LocalMinRecoveryPointTLI = ControlFile->minRecoveryPointTLI;
2715 : :
129 alvherre@kurilemu.de 2716 [ + + ]:GNC 7272 : if (!XLogRecPtrIsValid(LocalMinRecoveryPoint))
2753 michael@paquier.xyz 2717 :CBC 2 : updateMinRecoveryPoint = false;
1488 heikki.linnakangas@i 2718 [ + + + + ]: 7270 : else if (force || LocalMinRecoveryPoint < lsn)
2719 : : {
2720 : : XLogRecPtr newMinRecoveryPoint;
2721 : : TimeLineID newMinRecoveryPointTLI;
2722 : :
2723 : : /*
2724 : : * To avoid having to update the control file too often, we update it
2725 : : * all the way to the last record being replayed, even though 'lsn'
2726 : : * would suffice for correctness. This also allows the 'force' case
2727 : : * to not need a valid 'lsn' value.
2728 : : *
2729 : : * Another important reason for doing it this way is that the passed
2730 : : * 'lsn' value could be bogus, i.e., past the end of available WAL, if
2731 : : * the caller got it from a corrupted heap page. Accepting such a
2732 : : * value as the min recovery point would prevent us from coming up at
2733 : : * all. Instead, we just log a warning and continue with recovery.
2734 : : * (See also the comments about corrupt LSNs in XLogFlush.)
2735 : : */
2736 : 5730 : newMinRecoveryPoint = GetCurrentReplayRecPtr(&newMinRecoveryPointTLI);
4825 alvherre@alvh.no-ip. 2737 [ + + - + ]: 5730 : if (!force && newMinRecoveryPoint < lsn)
6106 tgl@sss.pgh.pa.us 2738 [ # # ]:UBC 0 : elog(WARNING,
2739 : : "xlog min recovery request %X/%08X is past current point %X/%08X",
2740 : : LSN_FORMAT_ARGS(lsn), LSN_FORMAT_ARGS(newMinRecoveryPoint));
2741 : :
2742 : : /* update control file */
4825 alvherre@alvh.no-ip. 2743 [ + + ]:CBC 5730 : if (ControlFile->minRecoveryPoint < newMinRecoveryPoint)
2744 : : {
6234 heikki.linnakangas@i 2745 : 5378 : ControlFile->minRecoveryPoint = newMinRecoveryPoint;
4849 2746 : 5378 : ControlFile->minRecoveryPointTLI = newMinRecoveryPointTLI;
6234 2747 : 5378 : UpdateControlFile();
1488 2748 : 5378 : LocalMinRecoveryPoint = newMinRecoveryPoint;
2749 : 5378 : LocalMinRecoveryPointTLI = newMinRecoveryPointTLI;
2750 : :
6234 2751 [ + + ]: 5378 : ereport(DEBUG2,
2752 : : errmsg_internal("updated min recovery point to %X/%08X on timeline %u",
2753 : : LSN_FORMAT_ARGS(newMinRecoveryPoint),
2754 : : newMinRecoveryPointTLI));
2755 : : }
2756 : : }
2757 : 7272 : LWLockRelease(ControlFileLock);
2758 : : }
2759 : :
2760 : : /*
2761 : : * Ensure that all XLOG data through the given position is flushed to disk.
2762 : : *
2763 : : * NOTE: this differs from XLogWrite mainly in that the WALWriteLock is not
2764 : : * already held, and we try to avoid acquiring it if possible.
2765 : : */
2766 : : void
9133 tgl@sss.pgh.pa.us 2767 : 734742 : XLogFlush(XLogRecPtr record)
2768 : : {
2769 : : XLogRecPtr WriteRqstPtr;
2770 : : XLogwrtRqst WriteRqst;
1586 rhaas@postgresql.org 2771 : 734742 : TimeLineID insertTLI = XLogCtl->InsertTimeLineID;
2772 : :
2773 : : /*
2774 : : * During REDO, we are reading not writing WAL. Therefore, instead of
2775 : : * trying to flush the WAL, we should update minRecoveryPoint instead. We
2776 : : * test XLogInsertAllowed(), not InRecovery, because we need checkpointer
2777 : : * to act this way too, and because when it tries to write the
2778 : : * end-of-recovery checkpoint, it should indeed flush.
2779 : : */
6106 tgl@sss.pgh.pa.us 2780 [ + + ]: 734742 : if (!XLogInsertAllowed())
2781 : : {
6234 heikki.linnakangas@i 2782 : 110542 : UpdateMinRecoveryPoint(record, false);
9133 tgl@sss.pgh.pa.us 2783 : 589990 : return;
2784 : : }
2785 : :
2786 : : /* Quick exit if already known flushed */
4825 alvherre@alvh.no-ip. 2787 [ + + ]: 624200 : if (record <= LogwrtResult.Flush)
9133 tgl@sss.pgh.pa.us 2788 : 479448 : return;
2789 : :
2790 : : #ifdef WAL_DEBUG
2791 : : if (XLOG_DEBUG)
2792 : : elog(LOG, "xlog flush request %X/%08X; write %X/%08X; flush %X/%08X",
2793 : : LSN_FORMAT_ARGS(record),
2794 : : LSN_FORMAT_ARGS(LogwrtResult.Write),
2795 : : LSN_FORMAT_ARGS(LogwrtResult.Flush));
2796 : : #endif
2797 : :
2798 : 144752 : START_CRIT_SECTION();
2799 : :
2800 : : /*
2801 : : * Since fsync is usually a horribly expensive operation, we try to
2802 : : * piggyback as much data as we can on each fsync: if we see any more data
2803 : : * entered into the xlog buffer, we'll write and fsync that too, so that
2804 : : * the final value of LogwrtResult.Flush is as large as possible. This
2805 : : * gives us some chance of avoiding another fsync immediately after.
2806 : : */
2807 : :
2808 : : /* initialize to given target; may increase below */
2809 : 144752 : WriteRqstPtr = record;
2810 : :
2811 : : /*
2812 : : * Now wait until we get the write lock, or someone else does the flush
2813 : : * for us.
2814 : : */
2815 : : for (;;)
8843 2816 : 2152 : {
2817 : : XLogRecPtr insertpos;
2818 : :
2819 : : /* done already? */
709 alvherre@alvh.no-ip. 2820 : 146904 : RefreshXLogWriteResult(LogwrtResult);
4825 2821 [ + + ]: 146904 : if (record <= LogwrtResult.Flush)
5158 heikki.linnakangas@i 2822 : 12796 : break;
2823 : :
2824 : : /*
2825 : : * Before actually performing the write, wait for all in-flight
2826 : : * insertions to the pages we're about to write to finish.
2827 : : */
709 alvherre@alvh.no-ip. 2828 [ + + ]: 134108 : SpinLockAcquire(&XLogCtl->info_lck);
2829 [ + + ]: 134108 : if (WriteRqstPtr < XLogCtl->LogwrtRqst.Write)
2830 : 9972 : WriteRqstPtr = XLogCtl->LogwrtRqst.Write;
2831 : 134108 : SpinLockRelease(&XLogCtl->info_lck);
4633 heikki.linnakangas@i 2832 : 134108 : insertpos = WaitXLogInsertionsToFinish(WriteRqstPtr);
2833 : :
2834 : : /*
2835 : : * Try to get the write lock. If we can't get it immediately, wait
2836 : : * until it's released, and recheck if we still need to do the flush
2837 : : * or if the backend that held the lock did it for us already. This
2838 : : * helps to maintain a good rate of group committing when the system
2839 : : * is bottlenecked by the speed of fsyncing.
2840 : : */
5149 2841 [ + + ]: 134108 : if (!LWLockAcquireOrWait(WALWriteLock, LW_EXCLUSIVE))
2842 : : {
2843 : : /*
2844 : : * The lock is now free, but we didn't acquire it yet. Before we
2845 : : * do, loop back to check if someone else flushed the record for
2846 : : * us already.
2847 : : */
5158 2848 : 2152 : continue;
2849 : : }
2850 : :
2851 : : /* Got the lock; recheck whether request is satisfied */
711 alvherre@alvh.no-ip. 2852 : 131956 : RefreshXLogWriteResult(LogwrtResult);
4825 2853 [ + + ]: 131956 : if (record <= LogwrtResult.Flush)
2854 : : {
5004 rhaas@postgresql.org 2855 : 3601 : LWLockRelease(WALWriteLock);
2856 : 3601 : break;
2857 : : }
2858 : :
2859 : : /*
2860 : : * Sleep before flush! By adding a delay here, we may give further
2861 : : * backends the opportunity to join the backlog of group commit
2862 : : * followers; this can significantly improve transaction throughput,
2863 : : * at the risk of increasing transaction latency.
2864 : : *
2865 : : * We do not sleep if enableFsync is not turned on, nor if there are
2866 : : * fewer than CommitSiblings other backends with active transactions.
2867 : : */
2868 [ - + - - : 128355 : if (CommitDelay > 0 && enableFsync &&
- - ]
5004 rhaas@postgresql.org 2869 :UBC 0 : MinimumActiveBackends(CommitSiblings))
2870 : : {
96 heikki.linnakangas@i 2871 :UNC 0 : pgstat_report_wait_start(WAIT_EVENT_COMMIT_DELAY);
5004 rhaas@postgresql.org 2872 :UBC 0 : pg_usleep(CommitDelay);
96 heikki.linnakangas@i 2873 :UNC 0 : pgstat_report_wait_end();
2874 : :
2875 : : /*
2876 : : * Re-check how far we can now flush the WAL. It's generally not
2877 : : * safe to call WaitXLogInsertionsToFinish while holding
2878 : : * WALWriteLock, because an in-progress insertion might need to
2879 : : * also grab WALWriteLock to make progress. But we know that all
2880 : : * the insertions up to insertpos have already finished, because
2881 : : * that's what the earlier WaitXLogInsertionsToFinish() returned.
2882 : : * We're only calling it again to allow insertpos to be moved
2883 : : * further forward, not to actually wait for anyone.
2884 : : */
4633 heikki.linnakangas@i 2885 :UBC 0 : insertpos = WaitXLogInsertionsToFinish(insertpos);
2886 : : }
2887 : :
2888 : : /* try to write/flush later additions to XLOG as well */
4633 heikki.linnakangas@i 2889 :CBC 128355 : WriteRqst.Write = insertpos;
2890 : 128355 : WriteRqst.Flush = insertpos;
2891 : :
1591 rhaas@postgresql.org 2892 : 128355 : XLogWrite(WriteRqst, insertTLI, false);
2893 : :
8933 tgl@sss.pgh.pa.us 2894 : 128355 : LWLockRelease(WALWriteLock);
2895 : : /* done */
5158 heikki.linnakangas@i 2896 : 128355 : break;
2897 : : }
2898 : :
9133 tgl@sss.pgh.pa.us 2899 [ - + ]: 144752 : END_CRIT_SECTION();
2900 : :
2901 : : /* wake up walsenders now that we've released heavily contended locks */
1072 andres@anarazel.de 2902 : 144752 : WalSndWakeupProcessRequests(true, !RecoveryInProgress());
2903 : :
2904 : : /*
2905 : : * If we flushed an LSN that someone was waiting for, notify the waiters.
2906 : : */
69 akorotkov@postgresql 2907 [ + - - + ]:GNC 289504 : if (waitLSNState &&
2908 : 144752 : (LogwrtResult.Flush >=
2909 : 144752 : pg_atomic_read_u64(&waitLSNState->minWaitedLSN[WAIT_LSN_TYPE_PRIMARY_FLUSH])))
69 akorotkov@postgresql 2910 :UNC 0 : WaitLSNWakeup(WAIT_LSN_TYPE_PRIMARY_FLUSH, LogwrtResult.Flush);
2911 : :
2912 : : /*
2913 : : * If we still haven't flushed to the request point then we have a
2914 : : * problem; most likely, the requested flush point is past end of XLOG.
2915 : : * This has been seen to occur when a disk page has a corrupted LSN.
2916 : : *
2917 : : * Formerly we treated this as a PANIC condition, but that hurts the
2918 : : * system's robustness rather than helping it: we do not want to take down
2919 : : * the whole system due to corruption on one data page. In particular, if
2920 : : * the bad page is encountered again during recovery then we would be
2921 : : * unable to restart the database at all! (This scenario actually
2922 : : * happened in the field several times with 7.1 releases.) As of 8.4, bad
2923 : : * LSNs encountered during recovery are UpdateMinRecoveryPoint's problem;
2924 : : * the only time we can reach here during recovery is while flushing the
2925 : : * end-of-recovery checkpoint record, and we don't expect that to have a
2926 : : * bad LSN.
2927 : : *
2928 : : * Note that for calls from xact.c, the ERROR will be promoted to PANIC
2929 : : * since xact.c calls this routine inside a critical section. However,
2930 : : * calls from bufmgr.c are not within critical sections and so we will not
2931 : : * force a restart for a bad LSN on a data page.
2932 : : */
4825 alvherre@alvh.no-ip. 2933 [ - + ]:CBC 144752 : if (LogwrtResult.Flush < record)
6106 tgl@sss.pgh.pa.us 2934 [ # # ]:UBC 0 : elog(ERROR,
2935 : : "xlog flush request %X/%08X is not satisfied --- flushed only to %X/%08X",
2936 : : LSN_FORMAT_ARGS(record),
2937 : : LSN_FORMAT_ARGS(LogwrtResult.Flush));
2938 : :
2939 : : /*
2940 : : * Cross-check XLogNeedsFlush(). Some of the checks of XLogFlush() and
2941 : : * XLogNeedsFlush() are duplicated, and this assertion ensures that these
2942 : : * remain consistent.
2943 : : */
177 michael@paquier.xyz 2944 [ - + ]:GNC 144752 : Assert(!XLogNeedsFlush(record));
2945 : : }
2946 : :
2947 : : /*
2948 : : * Write & flush xlog, but without specifying exactly where to.
2949 : : *
2950 : : * We normally write only completed blocks; but if there is nothing to do on
2951 : : * that basis, we check for unwritten async commits in the current incomplete
2952 : : * block, and write through the latest one of those. Thus, if async commits
2953 : : * are not being used, we will write complete blocks only.
2954 : : *
2955 : : * If, based on the above, there's anything to write we do so immediately. But
2956 : : * to avoid calling fsync, fdatasync et. al. at a rate that'd impact
2957 : : * concurrent IO, we only flush WAL every wal_writer_delay ms, or if there's
2958 : : * more than wal_writer_flush_after unflushed blocks.
2959 : : *
2960 : : * We can guarantee that async commits reach disk after at most three
2961 : : * wal_writer_delay cycles. (When flushing complete blocks, we allow XLogWrite
2962 : : * to write "flexibly", meaning it can stop at the end of the buffer ring;
2963 : : * this makes a difference only with very high load or long wal_writer_delay,
2964 : : * but imposes one extra cycle for the worst case for async commits.)
2965 : : *
2966 : : * This routine is invoked periodically by the background walwriter process.
2967 : : *
2968 : : * Returns true if there was any work to do, even if we skipped flushing due
2969 : : * to wal_writer_delay/wal_writer_flush_after.
2970 : : */
2971 : : bool
6809 tgl@sss.pgh.pa.us 2972 :CBC 11824 : XLogBackgroundFlush(void)
2973 : : {
2974 : : XLogwrtRqst WriteRqst;
2975 : 11824 : bool flexible = true;
2976 : : static TimestampTz lastflush;
2977 : : TimestampTz now;
2978 : : int flushblocks;
2979 : : TimeLineID insertTLI;
2980 : :
2981 : : /* XLOG doesn't need flushing during recovery */
6234 heikki.linnakangas@i 2982 [ - + ]: 11824 : if (RecoveryInProgress())
5059 tgl@sss.pgh.pa.us 2983 :UBC 0 : return false;
2984 : :
2985 : : /*
2986 : : * Since we're not in recovery, InsertTimeLineID is set and can't change,
2987 : : * so we can read it without a lock.
2988 : : */
1586 rhaas@postgresql.org 2989 :CBC 11824 : insertTLI = XLogCtl->InsertTimeLineID;
2990 : :
2991 : : /* read updated LogwrtRqst */
4192 andres@anarazel.de 2992 [ - + ]: 11824 : SpinLockAcquire(&XLogCtl->info_lck);
3681 2993 : 11824 : WriteRqst = XLogCtl->LogwrtRqst;
4192 2994 : 11824 : SpinLockRelease(&XLogCtl->info_lck);
2995 : :
2996 : : /* back off to last completed page boundary */
3681 2997 : 11824 : WriteRqst.Write -= WriteRqst.Write % XLOG_BLCKSZ;
2998 : :
2999 : : /* if we have already flushed that far, consider async commit records */
709 alvherre@alvh.no-ip. 3000 : 11824 : RefreshXLogWriteResult(LogwrtResult);
3681 andres@anarazel.de 3001 [ + + ]: 11824 : if (WriteRqst.Write <= LogwrtResult.Flush)
3002 : : {
4192 3003 [ - + ]: 8938 : SpinLockAcquire(&XLogCtl->info_lck);
3681 3004 : 8938 : WriteRqst.Write = XLogCtl->asyncXactLSN;
4192 3005 : 8938 : SpinLockRelease(&XLogCtl->info_lck);
6809 tgl@sss.pgh.pa.us 3006 : 8938 : flexible = false; /* ensure it all gets written */
3007 : : }
3008 : :
3009 : : /*
3010 : : * If already known flushed, we're done. Just need to check if we are
3011 : : * holding an open file handle to a logfile that's no longer in use,
3012 : : * preventing the file from being deleted.
3013 : : */
3681 andres@anarazel.de 3014 [ + + ]: 11824 : if (WriteRqst.Write <= LogwrtResult.Flush)
3015 : : {
5731 bruce@momjian.us 3016 [ + + ]: 8193 : if (openLogFile >= 0)
3017 : : {
3099 andres@anarazel.de 3018 [ + + ]: 5063 : if (!XLByteInPrevSeg(LogwrtResult.Write, openLogSegNo,
3019 : : wal_segment_size))
3020 : : {
5758 magnus@hagander.net 3021 : 191 : XLogFileClose();
3022 : : }
3023 : : }
5059 tgl@sss.pgh.pa.us 3024 : 8193 : return false;
3025 : : }
3026 : :
3027 : : /*
3028 : : * Determine how far to flush WAL, based on the wal_writer_delay and
3029 : : * wal_writer_flush_after GUCs.
3030 : : *
3031 : : * Note that XLogSetAsyncXactLSN() performs similar calculation based on
3032 : : * wal_writer_flush_after, to decide when to wake us up. Make sure the
3033 : : * logic is the same in both places if you change this.
3034 : : */
3681 andres@anarazel.de 3035 : 3631 : now = GetCurrentTimestamp();
839 heikki.linnakangas@i 3036 : 3631 : flushblocks =
3681 andres@anarazel.de 3037 : 3631 : WriteRqst.Write / XLOG_BLCKSZ - LogwrtResult.Flush / XLOG_BLCKSZ;
3038 : :
3039 [ + - + + ]: 3631 : if (WalWriterFlushAfter == 0 || lastflush == 0)
3040 : : {
3041 : : /* first call, or block based limits disabled */
3042 : 274 : WriteRqst.Flush = WriteRqst.Write;
3043 : 274 : lastflush = now;
3044 : : }
3045 [ + + ]: 3357 : else if (TimestampDifferenceExceeds(lastflush, now, WalWriterDelay))
3046 : : {
3047 : : /*
3048 : : * Flush the writes at least every WalWriterDelay ms. This is
3049 : : * important to bound the amount of time it takes for an asynchronous
3050 : : * commit to hit disk.
3051 : : */
3052 : 3203 : WriteRqst.Flush = WriteRqst.Write;
3053 : 3203 : lastflush = now;
3054 : : }
839 heikki.linnakangas@i 3055 [ + + ]: 154 : else if (flushblocks >= WalWriterFlushAfter)
3056 : : {
3057 : : /* exceeded wal_writer_flush_after blocks, flush */
3681 andres@anarazel.de 3058 : 135 : WriteRqst.Flush = WriteRqst.Write;
3059 : 135 : lastflush = now;
3060 : : }
3061 : : else
3062 : : {
3063 : : /* no flushing, this time round */
45 alvherre@kurilemu.de 3064 :GNC 19 : WriteRqst.Flush = InvalidXLogRecPtr;
3065 : : }
3066 : :
3067 : : #ifdef WAL_DEBUG
3068 : : if (XLOG_DEBUG)
3069 : : elog(LOG, "xlog bg flush request write %X/%08X; flush: %X/%08X, current is write %X/%08X; flush %X/%08X",
3070 : : LSN_FORMAT_ARGS(WriteRqst.Write),
3071 : : LSN_FORMAT_ARGS(WriteRqst.Flush),
3072 : : LSN_FORMAT_ARGS(LogwrtResult.Write),
3073 : : LSN_FORMAT_ARGS(LogwrtResult.Flush));
3074 : : #endif
3075 : :
6809 tgl@sss.pgh.pa.us 3076 :CBC 3631 : START_CRIT_SECTION();
3077 : :
3078 : : /* now wait for any in-progress insertions to finish and get write lock */
3681 andres@anarazel.de 3079 : 3631 : WaitXLogInsertionsToFinish(WriteRqst.Write);
6809 tgl@sss.pgh.pa.us 3080 : 3631 : LWLockAcquire(WALWriteLock, LW_EXCLUSIVE);
711 alvherre@alvh.no-ip. 3081 : 3631 : RefreshXLogWriteResult(LogwrtResult);
3681 andres@anarazel.de 3082 [ + + ]: 3631 : if (WriteRqst.Write > LogwrtResult.Write ||
3083 [ + + ]: 174 : WriteRqst.Flush > LogwrtResult.Flush)
3084 : : {
1591 rhaas@postgresql.org 3085 : 3563 : XLogWrite(WriteRqst, insertTLI, flexible);
3086 : : }
6809 tgl@sss.pgh.pa.us 3087 : 3631 : LWLockRelease(WALWriteLock);
3088 : :
3089 [ - + ]: 3631 : END_CRIT_SECTION();
3090 : :
3091 : : /* wake up walsenders now that we've released heavily contended locks */
1072 andres@anarazel.de 3092 : 3631 : WalSndWakeupProcessRequests(true, !RecoveryInProgress());
3093 : :
3094 : : /*
3095 : : * If we flushed an LSN that someone was waiting for, notify the waiters.
3096 : : */
69 akorotkov@postgresql 3097 [ + - - + ]:GNC 7262 : if (waitLSNState &&
3098 : 3631 : (LogwrtResult.Flush >=
3099 : 3631 : pg_atomic_read_u64(&waitLSNState->minWaitedLSN[WAIT_LSN_TYPE_PRIMARY_FLUSH])))
69 akorotkov@postgresql 3100 :UNC 0 : WaitLSNWakeup(WAIT_LSN_TYPE_PRIMARY_FLUSH, LogwrtResult.Flush);
3101 : :
3102 : : /*
3103 : : * Great, done. To take some work off the critical path, try to initialize
3104 : : * as many of the no-longer-needed WAL buffers for future use as we can.
3105 : : */
1591 rhaas@postgresql.org 3106 :CBC 3631 : AdvanceXLInsertBuffer(InvalidXLogRecPtr, insertTLI, true);
3107 : :
3108 : : /*
3109 : : * If we determined that we need to write data, but somebody else
3110 : : * wrote/flushed already, it should be considered as being active, to
3111 : : * avoid hibernating too early.
3112 : : */
3681 andres@anarazel.de 3113 : 3631 : return true;
3114 : : }
3115 : :
3116 : : /*
3117 : : * Test whether XLOG data has been flushed up to (at least) the given
3118 : : * position, or whether the minimum recovery point has been updated past
3119 : : * the given position.
3120 : : *
3121 : : * Returns true if a flush is still needed, or if the minimum recovery point
3122 : : * must be updated.
3123 : : *
3124 : : * It is possible that someone else is already in the process of flushing
3125 : : * that far, or has updated the minimum recovery point up to the given
3126 : : * position.
3127 : : */
3128 : : bool
6864 tgl@sss.pgh.pa.us 3129 : 9629322 : XLogNeedsFlush(XLogRecPtr record)
3130 : : {
3131 : : /*
3132 : : * During recovery, we don't flush WAL but update minRecoveryPoint
3133 : : * instead. So "needs flush" is taken to mean whether minRecoveryPoint
3134 : : * would need to be updated.
3135 : : *
3136 : : * Using XLogInsertAllowed() rather than RecoveryInProgress() matters for
3137 : : * the case of an end-of-recovery checkpoint, where WAL data is flushed.
3138 : : * This check should be consistent with the one in XLogFlush().
3139 : : */
177 michael@paquier.xyz 3140 [ + + ]:GNC 9629322 : if (!XLogInsertAllowed())
3141 : : {
3142 : : /* Quick exit if already known to be updated or cannot be updated */
166 3143 [ + - + + ]: 593560 : if (!updateMinRecoveryPoint || record <= LocalMinRecoveryPoint)
3144 : 585179 : return false;
3145 : :
3146 : : /*
3147 : : * An invalid minRecoveryPoint means that we need to recover all the
3148 : : * WAL, i.e., we're doing crash recovery. We never modify the control
3149 : : * file's value in that case, so we can short-circuit future checks
3150 : : * here too. This triggers a quick exit path for the startup process,
3151 : : * which cannot update its local copy of minRecoveryPoint as long as
3152 : : * it has not replayed all WAL available when doing crash recovery.
3153 : : */
129 alvherre@kurilemu.de 3154 [ + + - + ]: 8381 : if (!XLogRecPtrIsValid(LocalMinRecoveryPoint) && InRecovery)
3155 : : {
2810 michael@paquier.xyz 3156 :UBC 0 : updateMinRecoveryPoint = false;
5930 simon@2ndQuadrant.co 3157 :LBC (584215) : return false;
3158 : : }
3159 : :
3160 : : /*
3161 : : * Update local copy of minRecoveryPoint. But if the lock is busy,
3162 : : * just return a conservative guess.
3163 : : */
5930 simon@2ndQuadrant.co 3164 [ - + ]:CBC 8381 : if (!LWLockConditionalAcquire(ControlFileLock, LW_SHARED))
5930 simon@2ndQuadrant.co 3165 :LBC (1) : return true;
1488 heikki.linnakangas@i 3166 :CBC 8381 : LocalMinRecoveryPoint = ControlFile->minRecoveryPoint;
3167 : 8381 : LocalMinRecoveryPointTLI = ControlFile->minRecoveryPointTLI;
5930 simon@2ndQuadrant.co 3168 : 8381 : LWLockRelease(ControlFileLock);
3169 : :
3170 : : /*
3171 : : * Check minRecoveryPoint for any other process than the startup
3172 : : * process doing crash recovery, which should not update the control
3173 : : * file value if crash recovery is still running.
3174 : : */
129 alvherre@kurilemu.de 3175 [ - + ]:GNC 8381 : if (!XLogRecPtrIsValid(LocalMinRecoveryPoint))
2753 michael@paquier.xyz 3176 :UBC 0 : updateMinRecoveryPoint = false;
3177 : :
3178 : : /* check again */
1488 heikki.linnakangas@i 3179 [ + + - + ]:CBC 8381 : if (record <= LocalMinRecoveryPoint || !updateMinRecoveryPoint)
2753 michael@paquier.xyz 3180 : 81 : return false;
3181 : : else
3182 : 8300 : return true;
3183 : : }
3184 : :
3185 : : /* Quick exit if already known flushed */
4825 alvherre@alvh.no-ip. 3186 [ + + ]: 9035762 : if (record <= LogwrtResult.Flush)
6864 tgl@sss.pgh.pa.us 3187 : 8841401 : return false;
3188 : :
3189 : : /* read LogwrtResult and update local state */
711 alvherre@alvh.no-ip. 3190 : 194361 : RefreshXLogWriteResult(LogwrtResult);
3191 : :
3192 : : /* check again */
4825 3193 [ + + ]: 194361 : if (record <= LogwrtResult.Flush)
6864 tgl@sss.pgh.pa.us 3194 : 2765 : return false;
3195 : :
3196 : 191596 : return true;
3197 : : }
3198 : :
3199 : : /*
3200 : : * Try to make a given XLOG file segment exist.
3201 : : *
3202 : : * logsegno: identify segment.
3203 : : *
3204 : : * *added: on return, true if this call raised the number of extant segments.
3205 : : *
3206 : : * path: on return, this char[MAXPGPATH] has the path to the logsegno file.
3207 : : *
3208 : : * Returns -1 or FD of opened file. A -1 here is not an error; a caller
3209 : : * wanting an open segment should attempt to open "path", which usually will
3210 : : * succeed. (This is weird, but it's efficient for the callers.)
3211 : : */
3212 : : static int
1591 rhaas@postgresql.org 3213 : 14889 : XLogFileInitInternal(XLogSegNo logsegno, TimeLineID logtli,
3214 : : bool *added, char *path)
3215 : : {
3216 : : char tmppath[MAXPGPATH];
3217 : : XLogSegNo installed_segno;
3218 : : XLogSegNo max_segno;
3219 : : int fd;
3220 : : int save_errno;
1072 tmunro@postgresql.or 3221 : 14889 : int open_flags = O_RDWR | O_CREAT | O_EXCL | PG_BINARY;
3222 : : instr_time io_start;
3223 : :
1591 rhaas@postgresql.org 3224 [ - + ]: 14889 : Assert(logtli != 0);
3225 : :
3226 : 14889 : XLogFilePath(path, logtli, logsegno, wal_segment_size);
3227 : :
3228 : : /*
3229 : : * Try to use existent file (checkpoint maker may have created it already)
3230 : : */
1721 noah@leadboat.com 3231 : 14889 : *added = false;
1108 tmunro@postgresql.or 3232 : 14889 : fd = BasicOpenFile(path, O_RDWR | PG_BINARY | O_CLOEXEC |
884 nathan@postgresql.or 3233 : 14889 : get_sync_bit(wal_sync_method));
1721 noah@leadboat.com 3234 [ + + ]: 14889 : if (fd < 0)
3235 : : {
3236 [ - + ]: 1466 : if (errno != ENOENT)
1721 noah@leadboat.com 3237 [ # # ]:UBC 0 : ereport(ERROR,
3238 : : (errcode_for_file_access(),
3239 : : errmsg("could not open file \"%s\": %m", path)));
3240 : : }
3241 : : else
1721 noah@leadboat.com 3242 :CBC 13423 : return fd;
3243 : :
3244 : : /*
3245 : : * Initialize an empty (all zeroes) segment. NOTE: it is possible that
3246 : : * another process is doing the same thing. If so, we will end up
3247 : : * pre-creating an extra log segment. That seems OK, and better than
3248 : : * holding the lock throughout this lengthy process.
3249 : : */
6833 tgl@sss.pgh.pa.us 3250 [ + + ]: 1466 : elog(DEBUG2, "creating and filling new WAL file");
3251 : :
7559 3252 : 1466 : snprintf(tmppath, MAXPGPATH, XLOGDIR "/xlogtemp.%d", (int) getpid());
3253 : :
9129 3254 : 1466 : unlink(tmppath);
3255 : :
1072 tmunro@postgresql.or 3256 [ - + ]: 1466 : if (io_direct_flags & IO_DIRECT_WAL_INIT)
1072 tmunro@postgresql.or 3257 :UBC 0 : open_flags |= PG_O_DIRECT;
3258 : :
3259 : : /* do not use get_sync_bit() here --- want to fsync only at end of fill */
1072 tmunro@postgresql.or 3260 :CBC 1466 : fd = BasicOpenFile(tmppath, open_flags);
9666 vadim4o@yahoo.com 3261 [ - + ]: 1466 : if (fd < 0)
7639 tgl@sss.pgh.pa.us 3262 [ # # ]:UBC 0 : ereport(ERROR,
3263 : : (errcode_for_file_access(),
3264 : : errmsg("could not create file \"%s\": %m", tmppath)));
3265 : :
3266 : : /* Measure I/O timing when initializing segment */
382 michael@paquier.xyz 3267 :CBC 1466 : io_start = pgstat_prepare_io_time(track_wal_io_timing);
3268 : :
2539 tmunro@postgresql.or 3269 : 1466 : pgstat_report_wait_start(WAIT_EVENT_WAL_INIT_WRITE);
3270 : 1466 : save_errno = 0;
3271 [ + - ]: 1466 : if (wal_init_zero)
3272 : : {
3273 : : ssize_t rc;
3274 : :
3275 : : /*
3276 : : * Zero-fill the file. With this setting, we do this the hard way to
3277 : : * ensure that all the file space has really been allocated. On
3278 : : * platforms that allow "holes" in files, just seeking to the end
3279 : : * doesn't allocate intermediate space. This way, we know that we
3280 : : * have all the space and (after the fsync below) that all the
3281 : : * indirect blocks are down on disk. Therefore, fdatasync(2) or
3282 : : * O_DSYNC will be sufficient to sync future writes to the log file.
3283 : : */
1105 michael@paquier.xyz 3284 : 1466 : rc = pg_pwrite_zeros(fd, wal_segment_size, 0);
3285 : :
1223 3286 [ - + ]: 1466 : if (rc < 0)
1223 michael@paquier.xyz 3287 :UBC 0 : save_errno = errno;
3288 : : }
3289 : : else
3290 : : {
3291 : : /*
3292 : : * Otherwise, seeking to the end and writing a solitary byte is
3293 : : * enough.
3294 : : */
4575 jdavis@postgresql.or 3295 : 0 : errno = 0;
1223 michael@paquier.xyz 3296 [ # # ]: 0 : if (pg_pwrite(fd, "\0", 1, wal_segment_size - 1) != 1)
3297 : : {
3298 : : /* if write didn't set errno, assume no disk space */
2539 tmunro@postgresql.or 3299 [ # # ]: 0 : save_errno = errno ? errno : ENOSPC;
3300 : : }
3301 : : }
2539 tmunro@postgresql.or 3302 :CBC 1466 : pgstat_report_wait_end();
3303 : :
3304 : : /*
3305 : : * A full segment worth of data is written when using wal_init_zero. One
3306 : : * byte is written when not using it.
3307 : : */
404 michael@paquier.xyz 3308 : 1466 : pgstat_count_io_op_time(IOOBJECT_WAL, IOCONTEXT_INIT, IOOP_WRITE,
3309 : : io_start, 1,
3310 [ + - ]: 1466 : wal_init_zero ? wal_segment_size : 1);
3311 : :
2539 tmunro@postgresql.or 3312 [ - + ]: 1466 : if (save_errno)
3313 : : {
3314 : : /*
3315 : : * If we fail to make the file, delete it to release disk space
3316 : : */
2539 tmunro@postgresql.or 3317 :UBC 0 : unlink(tmppath);
3318 : :
3319 : 0 : close(fd);
3320 : :
3321 : 0 : errno = save_errno;
3322 : :
3323 [ # # ]: 0 : ereport(ERROR,
3324 : : (errcode_for_file_access(),
3325 : : errmsg("could not write to file \"%s\": %m", tmppath)));
3326 : : }
3327 : :
3328 : : /* Measure I/O timing when flushing segment */
382 michael@paquier.xyz 3329 :CBC 1466 : io_start = pgstat_prepare_io_time(track_wal_io_timing);
3330 : :
3284 rhaas@postgresql.org 3331 : 1466 : pgstat_report_wait_start(WAIT_EVENT_WAL_INIT_SYNC);
9228 tgl@sss.pgh.pa.us 3332 [ - + ]: 1466 : if (pg_fsync(fd) != 0)
3333 : : {
1297 drowley@postgresql.o 3334 :UBC 0 : save_errno = errno;
4856 heikki.linnakangas@i 3335 : 0 : close(fd);
2820 michael@paquier.xyz 3336 : 0 : errno = save_errno;
7639 tgl@sss.pgh.pa.us 3337 [ # # ]: 0 : ereport(ERROR,
3338 : : (errcode_for_file_access(),
3339 : : errmsg("could not fsync file \"%s\": %m", tmppath)));
3340 : : }
3284 rhaas@postgresql.org 3341 :CBC 1466 : pgstat_report_wait_end();
3342 : :
404 michael@paquier.xyz 3343 : 1466 : pgstat_count_io_op_time(IOOBJECT_WAL, IOCONTEXT_INIT,
3344 : : IOOP_FSYNC, io_start, 1, 0);
3345 : :
2444 peter@eisentraut.org 3346 [ - + ]: 1466 : if (close(fd) != 0)
7639 tgl@sss.pgh.pa.us 3347 [ # # ]:UBC 0 : ereport(ERROR,
3348 : : (errcode_for_file_access(),
3349 : : errmsg("could not close file \"%s\": %m", tmppath)));
3350 : :
3351 : : /*
3352 : : * Now move the segment into place with its final name. Cope with
3353 : : * possibility that someone else has created the file while we were
3354 : : * filling ours: if so, use ours to pre-create a future log segment.
3355 : : */
5012 heikki.linnakangas@i 3356 :CBC 1466 : installed_segno = logsegno;
3357 : :
3358 : : /*
3359 : : * XXX: What should we use as max_segno? We used to use XLOGfileslop when
3360 : : * that was a constant, but that was always a bit dubious: normally, at a
3361 : : * checkpoint, XLOGfileslop was the offset from the checkpoint record, but
3362 : : * here, it was the offset from the insert location. We can't do the
3363 : : * normal XLOGfileslop calculation here because we don't have access to
3364 : : * the prior checkpoint's redo location. So somewhat arbitrarily, just use
3365 : : * CheckPointSegments.
3366 : : */
4038 3367 : 1466 : max_segno = logsegno + CheckPointSegments;
1591 rhaas@postgresql.org 3368 [ + - ]: 1466 : if (InstallXLogFileSegment(&installed_segno, tmppath, true, max_segno,
3369 : : logtli))
3370 : : {
1721 noah@leadboat.com 3371 : 1466 : *added = true;
3372 [ + + ]: 1466 : elog(DEBUG2, "done creating and filling new WAL file");
3373 : : }
3374 : : else
3375 : : {
3376 : : /*
3377 : : * No need for any more future segments, or InstallXLogFileSegment()
3378 : : * failed to rename the file into place. If the rename failed, a
3379 : : * caller opening the file may fail.
3380 : : */
9005 tgl@sss.pgh.pa.us 3381 :UBC 0 : unlink(tmppath);
1721 noah@leadboat.com 3382 [ # # ]: 0 : elog(DEBUG2, "abandoned new WAL file");
3383 : : }
3384 : :
1721 noah@leadboat.com 3385 :CBC 1466 : return -1;
3386 : : }
3387 : :
3388 : : /*
3389 : : * Create a new XLOG file segment, or open a pre-existing one.
3390 : : *
3391 : : * logsegno: identify segment to be created/opened.
3392 : : *
3393 : : * Returns FD of opened file.
3394 : : *
3395 : : * Note: errors here are ERROR not PANIC because we might or might not be
3396 : : * inside a critical section (eg, during checkpoint there is no reason to
3397 : : * take down the system on failure). They will promote to PANIC if we are
3398 : : * in a critical section.
3399 : : */
3400 : : int
1591 rhaas@postgresql.org 3401 : 14696 : XLogFileInit(XLogSegNo logsegno, TimeLineID logtli)
3402 : : {
3403 : : bool ignore_added;
3404 : : char path[MAXPGPATH];
3405 : : int fd;
3406 : :
3407 [ - + ]: 14696 : Assert(logtli != 0);
3408 : :
3409 : 14696 : fd = XLogFileInitInternal(logsegno, logtli, &ignore_added, path);
1721 noah@leadboat.com 3410 [ + + ]: 14696 : if (fd >= 0)
3411 : 13280 : return fd;
3412 : :
3413 : : /* Now open original target segment (might not be file I just made) */
1108 tmunro@postgresql.or 3414 : 1416 : fd = BasicOpenFile(path, O_RDWR | PG_BINARY | O_CLOEXEC |
884 nathan@postgresql.or 3415 : 1416 : get_sync_bit(wal_sync_method));
9005 tgl@sss.pgh.pa.us 3416 [ - + ]: 1416 : if (fd < 0)
7639 tgl@sss.pgh.pa.us 3417 [ # # ]:UBC 0 : ereport(ERROR,
3418 : : (errcode_for_file_access(),
3419 : : errmsg("could not open file \"%s\": %m", path)));
7368 neilc@samurai.com 3420 :CBC 1416 : return fd;
3421 : : }
3422 : :
3423 : : /*
3424 : : * Create a new XLOG file segment by copying a pre-existing one.
3425 : : *
3426 : : * destsegno: identify segment to be created.
3427 : : *
3428 : : * srcTLI, srcsegno: identify segment to be copied (could be from
3429 : : * a different timeline)
3430 : : *
3431 : : * upto: how much of the source file to copy (the rest is filled with
3432 : : * zeros)
3433 : : *
3434 : : * Currently this is only used during recovery, and so there are no locking
3435 : : * considerations. But we should be just as tense as XLogFileInit to avoid
3436 : : * emplacing a bogus file.
3437 : : */
3438 : : static void
1591 rhaas@postgresql.org 3439 : 43 : XLogFileCopy(TimeLineID destTLI, XLogSegNo destsegno,
3440 : : TimeLineID srcTLI, XLogSegNo srcsegno,
3441 : : int upto)
3442 : : {
3443 : : char path[MAXPGPATH];
3444 : : char tmppath[MAXPGPATH];
3445 : : PGAlignedXLogBlock buffer;
3446 : : int srcfd;
3447 : : int fd;
3448 : : int nbytes;
3449 : :
3450 : : /*
3451 : : * Open the source file
3452 : : */
3099 andres@anarazel.de 3453 : 43 : XLogFilePath(path, srcTLI, srcsegno, wal_segment_size);
3095 peter_e@gmx.net 3454 : 43 : srcfd = OpenTransientFile(path, O_RDONLY | PG_BINARY);
7907 tgl@sss.pgh.pa.us 3455 [ - + ]: 43 : if (srcfd < 0)
7639 tgl@sss.pgh.pa.us 3456 [ # # ]:UBC 0 : ereport(ERROR,
3457 : : (errcode_for_file_access(),
3458 : : errmsg("could not open file \"%s\": %m", path)));
3459 : :
3460 : : /*
3461 : : * Copy into a temp file name.
3462 : : */
7559 tgl@sss.pgh.pa.us 3463 :CBC 43 : snprintf(tmppath, MAXPGPATH, XLOGDIR "/xlogtemp.%d", (int) getpid());
3464 : :
7907 3465 : 43 : unlink(tmppath);
3466 : :
3467 : : /* do not use get_sync_bit() here --- want to fsync only at end of fill */
3095 peter_e@gmx.net 3468 : 43 : fd = OpenTransientFile(tmppath, O_RDWR | O_CREAT | O_EXCL | PG_BINARY);
7907 tgl@sss.pgh.pa.us 3469 [ - + ]: 43 : if (fd < 0)
7639 tgl@sss.pgh.pa.us 3470 [ # # ]:UBC 0 : ereport(ERROR,
3471 : : (errcode_for_file_access(),
3472 : : errmsg("could not create file \"%s\": %m", tmppath)));
3473 : :
3474 : : /*
3475 : : * Do the data copying.
3476 : : */
3099 andres@anarazel.de 3477 [ + + ]:CBC 88107 : for (nbytes = 0; nbytes < wal_segment_size; nbytes += sizeof(buffer))
3478 : : {
3479 : : int nread;
3480 : :
4105 heikki.linnakangas@i 3481 : 88064 : nread = upto - nbytes;
3482 : :
3483 : : /*
3484 : : * The part that is not read from the source file is filled with
3485 : : * zeros.
3486 : : */
3487 [ + + ]: 88064 : if (nread < sizeof(buffer))
2752 tgl@sss.pgh.pa.us 3488 : 43 : memset(buffer.data, 0, sizeof(buffer));
3489 : :
4105 heikki.linnakangas@i 3490 [ + + ]: 88064 : if (nread > 0)
3491 : : {
3492 : : int r;
3493 : :
3494 [ + + ]: 2800 : if (nread > sizeof(buffer))
3495 : 2757 : nread = sizeof(buffer);
3284 rhaas@postgresql.org 3496 : 2800 : pgstat_report_wait_start(WAIT_EVENT_WAL_COPY_READ);
2752 tgl@sss.pgh.pa.us 3497 : 2800 : r = read(srcfd, buffer.data, nread);
2797 michael@paquier.xyz 3498 [ - + ]: 2800 : if (r != nread)
3499 : : {
2797 michael@paquier.xyz 3500 [ # # ]:UBC 0 : if (r < 0)
4105 heikki.linnakangas@i 3501 [ # # ]: 0 : ereport(ERROR,
3502 : : (errcode_for_file_access(),
3503 : : errmsg("could not read file \"%s\": %m",
3504 : : path)));
3505 : : else
3506 [ # # ]: 0 : ereport(ERROR,
3507 : : (errcode(ERRCODE_DATA_CORRUPTED),
3508 : : errmsg("could not read file \"%s\": read %d of %zu",
3509 : : path, r, (Size) nread)));
3510 : : }
3284 rhaas@postgresql.org 3511 :CBC 2800 : pgstat_report_wait_end();
3512 : : }
7907 tgl@sss.pgh.pa.us 3513 : 88064 : errno = 0;
3284 rhaas@postgresql.org 3514 : 88064 : pgstat_report_wait_start(WAIT_EVENT_WAL_COPY_WRITE);
2752 tgl@sss.pgh.pa.us 3515 [ - + ]: 88064 : if ((int) write(fd, buffer.data, sizeof(buffer)) != (int) sizeof(buffer))
3516 : : {
7907 tgl@sss.pgh.pa.us 3517 :UBC 0 : int save_errno = errno;
3518 : :
3519 : : /*
3520 : : * If we fail to make the file, delete it to release disk space
3521 : : */
3522 : 0 : unlink(tmppath);
3523 : : /* if write didn't set errno, assume problem is no disk space */
3524 [ # # ]: 0 : errno = save_errno ? save_errno : ENOSPC;
3525 : :
7639 3526 [ # # ]: 0 : ereport(ERROR,
3527 : : (errcode_for_file_access(),
3528 : : errmsg("could not write to file \"%s\": %m", tmppath)));
3529 : : }
3284 rhaas@postgresql.org 3530 :CBC 88064 : pgstat_report_wait_end();
3531 : : }
3532 : :
3533 : 43 : pgstat_report_wait_start(WAIT_EVENT_WAL_COPY_SYNC);
7907 tgl@sss.pgh.pa.us 3534 [ - + ]: 43 : if (pg_fsync(fd) != 0)
2673 tmunro@postgresql.or 3535 [ # # ]:UBC 0 : ereport(data_sync_elevel(ERROR),
3536 : : (errcode_for_file_access(),
3537 : : errmsg("could not fsync file \"%s\": %m", tmppath)));
3284 rhaas@postgresql.org 3538 :CBC 43 : pgstat_report_wait_end();
3539 : :
2444 peter@eisentraut.org 3540 [ - + ]: 43 : if (CloseTransientFile(fd) != 0)
7639 tgl@sss.pgh.pa.us 3541 [ # # ]:UBC 0 : ereport(ERROR,
3542 : : (errcode_for_file_access(),
3543 : : errmsg("could not close file \"%s\": %m", tmppath)));
3544 : :
2444 peter@eisentraut.org 3545 [ - + ]:CBC 43 : if (CloseTransientFile(srcfd) != 0)
2563 michael@paquier.xyz 3546 [ # # ]:UBC 0 : ereport(ERROR,
3547 : : (errcode_for_file_access(),
3548 : : errmsg("could not close file \"%s\": %m", path)));
3549 : :
3550 : : /*
3551 : : * Now move the segment into place with its final name.
3552 : : */
1591 rhaas@postgresql.org 3553 [ - + ]:CBC 43 : if (!InstallXLogFileSegment(&destsegno, tmppath, false, 0, destTLI))
3910 fujii@postgresql.org 3554 [ # # ]:UBC 0 : elog(ERROR, "InstallXLogFileSegment should not have failed");
7907 tgl@sss.pgh.pa.us 3555 :CBC 43 : }
3556 : :
3557 : : /*
3558 : : * Install a new XLOG segment file as a current or future log segment.
3559 : : *
3560 : : * This is used both to install a newly-created segment (which has a temp
3561 : : * filename while it's being created) and to recycle an old segment.
3562 : : *
3563 : : * *segno: identify segment to install as (or first possible target).
3564 : : * When find_free is true, this is modified on return to indicate the
3565 : : * actual installation location or last segment searched.
3566 : : *
3567 : : * tmppath: initial name of file to install. It will be renamed into place.
3568 : : *
3569 : : * find_free: if true, install the new segment at the first empty segno
3570 : : * number at or after the passed numbers. If false, install the new segment
3571 : : * exactly where specified, deleting any existing segment file there.
3572 : : *
3573 : : * max_segno: maximum segment number to install the new file as. Fail if no
3574 : : * free slot is found between *segno and max_segno. (Ignored when find_free
3575 : : * is false.)
3576 : : *
3577 : : * tli: The timeline on which the new segment should be installed.
3578 : : *
3579 : : * Returns true if the file was installed successfully. false indicates that
3580 : : * max_segno limit was exceeded, the startup process has disabled this
3581 : : * function for now, or an error occurred while renaming the file into place.
3582 : : */
3583 : : static bool
5012 heikki.linnakangas@i 3584 : 3151 : InstallXLogFileSegment(XLogSegNo *segno, char *tmppath,
3585 : : bool find_free, XLogSegNo max_segno, TimeLineID tli)
3586 : : {
3587 : : char path[MAXPGPATH];
3588 : : struct stat stat_buf;
3589 : :
1591 rhaas@postgresql.org 3590 [ - + ]: 3151 : Assert(tli != 0);
3591 : :
3592 : 3151 : XLogFilePath(path, tli, *segno, wal_segment_size);
3593 : :
1721 noah@leadboat.com 3594 : 3151 : LWLockAcquire(ControlFileLock, LW_EXCLUSIVE);
3595 [ - + ]: 3151 : if (!XLogCtl->InstallXLogFileSegmentActive)
3596 : : {
1721 noah@leadboat.com 3597 :UBC 0 : LWLockRelease(ControlFileLock);
3598 : 0 : return false;
3599 : : }
3600 : :
9005 tgl@sss.pgh.pa.us 3601 [ + + ]:CBC 3151 : if (!find_free)
3602 : : {
3603 : : /* Force installation: get rid of any pre-existing segment file */
3275 teodor@sigaev.ru 3604 : 43 : durable_unlink(path, DEBUG1);
3605 : : }
3606 : : else
3607 : : {
3608 : : /* Find a free slot to put it in */
8450 tgl@sss.pgh.pa.us 3609 [ + + ]: 4356 : while (stat(path, &stat_buf) == 0)
3610 : : {
4038 heikki.linnakangas@i 3611 [ + + ]: 1468 : if ((*segno) >= max_segno)
3612 : : {
3613 : : /* Failed to find a free slot within specified range */
1721 noah@leadboat.com 3614 : 220 : LWLockRelease(ControlFileLock);
9005 tgl@sss.pgh.pa.us 3615 : 220 : return false;
3616 : : }
5012 heikki.linnakangas@i 3617 : 1248 : (*segno)++;
1591 rhaas@postgresql.org 3618 : 1248 : XLogFilePath(path, tli, *segno, wal_segment_size);
3619 : : }
3620 : : }
3621 : :
1349 michael@paquier.xyz 3622 [ + - - + ]: 2931 : Assert(access(path, F_OK) != 0 && errno == ENOENT);
3623 [ - + ]: 2931 : if (durable_rename(tmppath, path, LOG) != 0)
3624 : : {
1721 noah@leadboat.com 3625 :UBC 0 : LWLockRelease(ControlFileLock);
3626 : : /* durable_rename already emitted log message */
6027 heikki.linnakangas@i 3627 : 0 : return false;
3628 : : }
3629 : :
1721 noah@leadboat.com 3630 :CBC 2931 : LWLockRelease(ControlFileLock);
3631 : :
9005 tgl@sss.pgh.pa.us 3632 : 2931 : return true;
3633 : : }
3634 : :
3635 : : /*
3636 : : * Open a pre-existing logfile segment for writing.
3637 : : */
3638 : : int
1591 rhaas@postgresql.org 3639 : 177 : XLogFileOpen(XLogSegNo segno, TimeLineID tli)
3640 : : {
3641 : : char path[MAXPGPATH];
3642 : : int fd;
3643 : :
3644 : 177 : XLogFilePath(path, tli, segno, wal_segment_size);
3645 : :
1108 tmunro@postgresql.or 3646 : 177 : fd = BasicOpenFile(path, O_RDWR | PG_BINARY | O_CLOEXEC |
884 nathan@postgresql.or 3647 : 177 : get_sync_bit(wal_sync_method));
9666 vadim4o@yahoo.com 3648 [ - + ]: 177 : if (fd < 0)
8273 tgl@sss.pgh.pa.us 3649 [ # # ]:UBC 0 : ereport(PANIC,
3650 : : (errcode_for_file_access(),
3651 : : errmsg("could not open file \"%s\": %m", path)));
3652 : :
7907 tgl@sss.pgh.pa.us 3653 :CBC 177 : return fd;
3654 : : }
3655 : :
3656 : : /*
3657 : : * Close the current logfile segment for writing.
3658 : : */
3659 : : static void
7213 bruce@momjian.us 3660 : 6740 : XLogFileClose(void)
3661 : : {
3662 [ - + ]: 6740 : Assert(openLogFile >= 0);
3663 : :
3664 : : /*
3665 : : * WAL segment files will not be re-read in normal operation, so we advise
3666 : : * the OS to release any cached pages. But do not do so if WAL archiving
3667 : : * or streaming is active, because archiver and walsender process could
3668 : : * use the cache to read the WAL segment.
3669 : : */
3670 : : #if defined(USE_POSIX_FADVISE) && defined(POSIX_FADV_DONTNEED)
1072 tmunro@postgresql.or 3671 [ + + + - ]: 6740 : if (!XLogIsNeeded() && (io_direct_flags & IO_DIRECT_WAL) == 0)
6272 tgl@sss.pgh.pa.us 3672 : 115 : (void) posix_fadvise(openLogFile, 0, 0, POSIX_FADV_DONTNEED);
3673 : : #endif
3674 : :
2444 peter@eisentraut.org 3675 [ - + ]: 6740 : if (close(openLogFile) != 0)
3676 : : {
3677 : : char xlogfname[MAXFNAMELEN];
2294 michael@paquier.xyz 3678 :UBC 0 : int save_errno = errno;
3679 : :
1591 rhaas@postgresql.org 3680 : 0 : XLogFileName(xlogfname, openLogTLI, openLogSegNo, wal_segment_size);
2294 michael@paquier.xyz 3681 : 0 : errno = save_errno;
7213 bruce@momjian.us 3682 [ # # ]: 0 : ereport(PANIC,
3683 : : (errcode_for_file_access(),
3684 : : errmsg("could not close file \"%s\": %m", xlogfname)));
3685 : : }
3686 : :
7213 bruce@momjian.us 3687 :CBC 6740 : openLogFile = -1;
2211 tgl@sss.pgh.pa.us 3688 : 6740 : ReleaseExternalFD();
7213 bruce@momjian.us 3689 : 6740 : }
3690 : :
3691 : : /*
3692 : : * Preallocate log files beyond the specified log endpoint.
3693 : : *
3694 : : * XXX this is currently extremely conservative, since it forces only one
3695 : : * future log segment to exist, and even that only if we are 75% done with
3696 : : * the current one. This is only appropriate for very low-WAL-volume systems.
3697 : : * High-volume systems will be OK once they've built up a sufficient set of
3698 : : * recycled log segments, but the startup transient is likely to include
3699 : : * a lot of segment creations by foreground processes, which is not so good.
3700 : : *
3701 : : * XLogFileInitInternal() can ereport(ERROR). All known causes indicate big
3702 : : * trouble; for example, a full filesystem is one cause. The checkpoint WAL
3703 : : * and/or ControlFile updates already completed. If a RequestCheckpoint()
3704 : : * initiated the present checkpoint and an ERROR ends this function, the
3705 : : * command that called RequestCheckpoint() fails. That's not ideal, but it's
3706 : : * not worth contorting more functions to use caller-specified elevel values.
3707 : : * (With or without RequestCheckpoint(), an ERROR forestalls some inessential
3708 : : * reporting and resource reclamation.)
3709 : : */
3710 : : static void
1591 rhaas@postgresql.org 3711 : 2076 : PreallocXlogFiles(XLogRecPtr endptr, TimeLineID tli)
3712 : : {
3713 : : XLogSegNo _logSegNo;
3714 : : int lf;
3715 : : bool added;
3716 : : char path[MAXPGPATH];
3717 : : uint64 offset;
3718 : :
1721 noah@leadboat.com 3719 [ + + ]: 2076 : if (!XLogCtl->InstallXLogFileSegmentActive)
3720 : 12 : return; /* unlocked check says no */
3721 : :
3099 andres@anarazel.de 3722 : 2064 : XLByteToPrevSeg(endptr, _logSegNo, wal_segment_size);
3723 : 2064 : offset = XLogSegmentOffset(endptr - 1, wal_segment_size);
3724 [ + + ]: 2064 : if (offset >= (uint32) (0.75 * wal_segment_size))
3725 : : {
5012 heikki.linnakangas@i 3726 : 193 : _logSegNo++;
1591 rhaas@postgresql.org 3727 : 193 : lf = XLogFileInitInternal(_logSegNo, tli, &added, path);
1721 noah@leadboat.com 3728 [ + + ]: 193 : if (lf >= 0)
3729 : 143 : close(lf);
3730 [ + + ]: 193 : if (added)
6833 tgl@sss.pgh.pa.us 3731 : 50 : CheckpointStats.ckpt_segs_added++;
3732 : : }
3733 : : }
3734 : :
3735 : : /*
3736 : : * Throws an error if the given log segment has already been removed or
3737 : : * recycled. The caller should only pass a segment that it knows to have
3738 : : * existed while the server has been running, as this function always
3739 : : * succeeds if no WAL segments have been removed since startup.
3740 : : * 'tli' is only used in the error message.
3741 : : *
3742 : : * Note: this function guarantees to keep errno unchanged on return.
3743 : : * This supports callers that use this to possibly deliver a better
3744 : : * error message about a missing file, while still being able to throw
3745 : : * a normal file-access error afterwards, if this does return.
3746 : : */
3747 : : void
4819 heikki.linnakangas@i 3748 : 131185 : CheckXLogRemoved(XLogSegNo segno, TimeLineID tli)
3749 : : {
3023 tgl@sss.pgh.pa.us 3750 : 131185 : int save_errno = errno;
3751 : : XLogSegNo lastRemovedSegNo;
3752 : :
4192 andres@anarazel.de 3753 [ + + ]: 131185 : SpinLockAcquire(&XLogCtl->info_lck);
3754 : 131185 : lastRemovedSegNo = XLogCtl->lastRemovedSegNo;
3755 : 131185 : SpinLockRelease(&XLogCtl->info_lck);
3756 : :
4819 heikki.linnakangas@i 3757 [ - + ]: 131185 : if (segno <= lastRemovedSegNo)
3758 : : {
3759 : : char filename[MAXFNAMELEN];
3760 : :
3099 andres@anarazel.de 3761 :UBC 0 : XLogFileName(filename, tli, segno, wal_segment_size);
3023 tgl@sss.pgh.pa.us 3762 : 0 : errno = save_errno;
4819 heikki.linnakangas@i 3763 [ # # ]: 0 : ereport(ERROR,
3764 : : (errcode_for_file_access(),
3765 : : errmsg("requested WAL segment %s has already been removed",
3766 : : filename)));
3767 : : }
3023 tgl@sss.pgh.pa.us 3768 :CBC 131185 : errno = save_errno;
5816 heikki.linnakangas@i 3769 : 131185 : }
3770 : :
3771 : : /*
3772 : : * Return the last WAL segment removed, or 0 if no segment has been removed
3773 : : * since startup.
3774 : : *
3775 : : * NB: the result can be out of date arbitrarily fast, the caller has to deal
3776 : : * with that.
3777 : : */
3778 : : XLogSegNo
4395 rhaas@postgresql.org 3779 : 1251 : XLogGetLastRemovedSegno(void)
3780 : : {
3781 : : XLogSegNo lastRemovedSegNo;
3782 : :
4192 andres@anarazel.de 3783 [ - + ]: 1251 : SpinLockAcquire(&XLogCtl->info_lck);
3784 : 1251 : lastRemovedSegNo = XLogCtl->lastRemovedSegNo;
3785 : 1251 : SpinLockRelease(&XLogCtl->info_lck);
3786 : :
4395 rhaas@postgresql.org 3787 : 1251 : return lastRemovedSegNo;
3788 : : }
3789 : :
3790 : : /*
3791 : : * Return the oldest WAL segment on the given TLI that still exists in
3792 : : * XLOGDIR, or 0 if none.
3793 : : */
3794 : : XLogSegNo
816 3795 : 7 : XLogGetOldestSegno(TimeLineID tli)
3796 : : {
3797 : : DIR *xldir;
3798 : : struct dirent *xlde;
3799 : 7 : XLogSegNo oldest_segno = 0;
3800 : :
3801 : 7 : xldir = AllocateDir(XLOGDIR);
3802 [ + + ]: 50 : while ((xlde = ReadDir(xldir, XLOGDIR)) != NULL)
3803 : : {
3804 : : TimeLineID file_tli;
3805 : : XLogSegNo file_segno;
3806 : :
3807 : : /* Ignore files that are not XLOG segments. */
3808 [ + + ]: 43 : if (!IsXLogFileName(xlde->d_name))
3809 : 29 : continue;
3810 : :
3811 : : /* Parse filename to get TLI and segno. */
3812 : 14 : XLogFromFileName(xlde->d_name, &file_tli, &file_segno,
3813 : : wal_segment_size);
3814 : :
3815 : : /* Ignore anything that's not from the TLI of interest. */
3816 [ - + ]: 14 : if (tli != file_tli)
816 rhaas@postgresql.org 3817 :UBC 0 : continue;
3818 : :
3819 : : /* If it's the oldest so far, update oldest_segno. */
816 rhaas@postgresql.org 3820 [ + + + + ]:CBC 14 : if (oldest_segno == 0 || file_segno < oldest_segno)
3821 : 9 : oldest_segno = file_segno;
3822 : : }
3823 : :
3824 : 7 : FreeDir(xldir);
3825 : 7 : return oldest_segno;
3826 : : }
3827 : :
3828 : : /*
3829 : : * Update the last removed segno pointer in shared memory, to reflect that the
3830 : : * given XLOG file has been removed.
3831 : : */
3832 : : static void
5816 heikki.linnakangas@i 3833 : 2596 : UpdateLastRemovedPtr(char *filename)
3834 : : {
3835 : : uint32 tli;
3836 : : XLogSegNo segno;
3837 : :
3099 andres@anarazel.de 3838 : 2596 : XLogFromFileName(filename, &tli, &segno, wal_segment_size);
3839 : :
4192 3840 [ + + ]: 2596 : SpinLockAcquire(&XLogCtl->info_lck);
3841 [ + + ]: 2596 : if (segno > XLogCtl->lastRemovedSegNo)
3842 : 1166 : XLogCtl->lastRemovedSegNo = segno;
3843 : 2596 : SpinLockRelease(&XLogCtl->info_lck);
5816 heikki.linnakangas@i 3844 : 2596 : }
3845 : :
3846 : : /*
3847 : : * Remove all temporary log files in pg_wal
3848 : : *
3849 : : * This is called at the beginning of recovery after a previous crash,
3850 : : * at a point where no other processes write fresh WAL data.
3851 : : */
3852 : : static void
2802 michael@paquier.xyz 3853 : 186 : RemoveTempXlogFiles(void)
3854 : : {
3855 : : DIR *xldir;
3856 : : struct dirent *xlde;
3857 : :
3858 [ + + ]: 186 : elog(DEBUG2, "removing all temporary WAL segments");
3859 : :
3860 : 186 : xldir = AllocateDir(XLOGDIR);
3861 [ + + ]: 1259 : while ((xlde = ReadDir(xldir, XLOGDIR)) != NULL)
3862 : : {
3863 : : char path[MAXPGPATH];
3864 : :
3865 [ + - ]: 1073 : if (strncmp(xlde->d_name, "xlogtemp.", 9) != 0)
3866 : 1073 : continue;
3867 : :
2802 michael@paquier.xyz 3868 :UBC 0 : snprintf(path, MAXPGPATH, XLOGDIR "/%s", xlde->d_name);
3869 : 0 : unlink(path);
3870 [ # # ]: 0 : elog(DEBUG2, "removed temporary WAL segment \"%s\"", path);
3871 : : }
2802 michael@paquier.xyz 3872 :CBC 186 : FreeDir(xldir);
3873 : 186 : }
3874 : :
3875 : : /*
3876 : : * Recycle or remove all log files older or equal to passed segno.
3877 : : *
3878 : : * endptr is current (or recent) end of xlog, and lastredoptr is the
3879 : : * redo pointer of the last checkpoint. These are used to determine
3880 : : * whether we want to recycle rather than delete no-longer-wanted log files.
3881 : : *
3882 : : * insertTLI is the current timeline for XLOG insertion. Any recycled
3883 : : * segments should be reused for this timeline.
3884 : : */
3885 : : static void
1591 rhaas@postgresql.org 3886 : 1802 : RemoveOldXlogFiles(XLogSegNo segno, XLogRecPtr lastredoptr, XLogRecPtr endptr,
3887 : : TimeLineID insertTLI)
3888 : : {
3889 : : DIR *xldir;
3890 : : struct dirent *xlde;
3891 : : char lastoff[MAXFNAMELEN];
3892 : : XLogSegNo endlogSegNo;
3893 : : XLogSegNo recycleSegNo;
3894 : :
3895 : : /* Initialize info about where to try to recycle to */
1885 michael@paquier.xyz 3896 : 1802 : XLByteToSeg(endptr, endlogSegNo, wal_segment_size);
3897 : 1802 : recycleSegNo = XLOGfileslop(lastredoptr);
3898 : :
3899 : : /*
3900 : : * Construct a filename of the last segment to be kept. The timeline ID
3901 : : * doesn't matter, we ignore that in the comparison. (During recovery,
3902 : : * InsertTimeLineID isn't set, so we can't use that.)
3903 : : */
3099 andres@anarazel.de 3904 : 1802 : XLogFileName(lastoff, 0, segno, wal_segment_size);
3905 : :
5676 simon@2ndQuadrant.co 3906 [ + + ]: 1802 : elog(DEBUG2, "attempting to remove WAL segments older than log file %s",
3907 : : lastoff);
3908 : :
3023 tgl@sss.pgh.pa.us 3909 : 1802 : xldir = AllocateDir(XLOGDIR);
3910 : :
7559 3911 [ + + ]: 44439 : while ((xlde = ReadDir(xldir, XLOGDIR)) != NULL)
3912 : : {
3913 : : /* Ignore files that are not XLOG segments */
3964 heikki.linnakangas@i 3914 [ + + ]: 42637 : if (!IsXLogFileName(xlde->d_name) &&
3915 [ + + ]: 7657 : !IsPartialXLogFileName(xlde->d_name))
3989 3916 : 7655 : continue;
3917 : :
3918 : : /*
3919 : : * We ignore the timeline part of the XLOG segment identifiers in
3920 : : * deciding whether a segment is still needed. This ensures that we
3921 : : * won't prematurely remove a segment from a parent timeline. We could
3922 : : * probably be a little more proactive about removing segments of
3923 : : * non-parent timelines, but that would be a whole lot more
3924 : : * complicated.
3925 : : *
3926 : : * We use the alphanumeric sorting property of the filenames to decide
3927 : : * which ones are earlier than the lastoff segment.
3928 : : */
3929 [ + + ]: 34982 : if (strcmp(xlde->d_name + 8, lastoff + 8) <= 0)
3930 : : {
4776 3931 [ + + ]: 28689 : if (XLogArchiveCheckDone(xlde->d_name))
3932 : : {
3933 : : /* Update the last removed location in shared memory first */
5816 3934 : 2596 : UpdateLastRemovedPtr(xlde->d_name);
3935 : :
1290 michael@paquier.xyz 3936 : 2596 : RemoveXlogFile(xlde, recycleSegNo, &endlogSegNo, insertTLI);
3937 : : }
3938 : : }
3939 : : }
3940 : :
3989 heikki.linnakangas@i 3941 : 1802 : FreeDir(xldir);
3942 : 1802 : }
3943 : :
3944 : : /*
3945 : : * Recycle or remove WAL files that are not part of the given timeline's
3946 : : * history.
3947 : : *
3948 : : * This is called during recovery, whenever we switch to follow a new
3949 : : * timeline, and at the end of recovery when we create a new timeline. We
3950 : : * wouldn't otherwise care about extra WAL files lying in pg_wal, but they
3951 : : * might be leftover pre-allocated or recycled WAL segments on the old timeline
3952 : : * that we haven't used yet, and contain garbage. If we just leave them in
3953 : : * pg_wal, they will eventually be archived, and we can't let that happen.
3954 : : * Files that belong to our timeline history are valid, because we have
3955 : : * successfully replayed them, but from others we can't be sure.
3956 : : *
3957 : : * 'switchpoint' is the current point in WAL where we switch to new timeline,
3958 : : * and 'newTLI' is the new timeline we switch to.
3959 : : */
3960 : : void
3961 : 67 : RemoveNonParentXlogFiles(XLogRecPtr switchpoint, TimeLineID newTLI)
3962 : : {
3963 : : DIR *xldir;
3964 : : struct dirent *xlde;
3965 : : char switchseg[MAXFNAMELEN];
3966 : : XLogSegNo endLogSegNo;
3967 : : XLogSegNo switchLogSegNo;
3968 : : XLogSegNo recycleSegNo;
3969 : :
3970 : : /*
3971 : : * Initialize info about where to begin the work. This will recycle,
3972 : : * somewhat arbitrarily, 10 future segments.
3973 : : */
1885 michael@paquier.xyz 3974 : 67 : XLByteToPrevSeg(switchpoint, switchLogSegNo, wal_segment_size);
3975 : 67 : XLByteToSeg(switchpoint, endLogSegNo, wal_segment_size);
3976 : 67 : recycleSegNo = endLogSegNo + 10;
3977 : :
3978 : : /*
3979 : : * Construct a filename of the last segment to be kept.
3980 : : */
3981 : 67 : XLogFileName(switchseg, newTLI, switchLogSegNo, wal_segment_size);
3982 : :
3989 heikki.linnakangas@i 3983 [ + + ]: 67 : elog(DEBUG2, "attempting to remove WAL segments newer than log file %s",
3984 : : switchseg);
3985 : :
3023 tgl@sss.pgh.pa.us 3986 : 67 : xldir = AllocateDir(XLOGDIR);
3987 : :
3989 heikki.linnakangas@i 3988 [ + + ]: 635 : while ((xlde = ReadDir(xldir, XLOGDIR)) != NULL)
3989 : : {
3990 : : /* Ignore files that are not XLOG segments */
3964 3991 [ + + ]: 568 : if (!IsXLogFileName(xlde->d_name))
3989 3992 : 353 : continue;
3993 : :
3994 : : /*
3995 : : * Remove files that are on a timeline older than the new one we're
3996 : : * switching to, but with a segment number >= the first segment on the
3997 : : * new timeline.
3998 : : */
3999 [ + + ]: 215 : if (strncmp(xlde->d_name, switchseg, 8) < 0 &&
4000 [ + + ]: 140 : strcmp(xlde->d_name + 8, switchseg + 8) > 0)
4001 : : {
4002 : : /*
4003 : : * If the file has already been marked as .ready, however, don't
4004 : : * remove it yet. It should be OK to remove it - files that are
4005 : : * not part of our timeline history are not required for recovery
4006 : : * - but seems safer to let them be archived and removed later.
4007 : : */
4008 [ + - ]: 16 : if (!XLogArchiveIsReady(xlde->d_name))
1290 michael@paquier.xyz 4009 : 16 : RemoveXlogFile(xlde, recycleSegNo, &endLogSegNo, newTLI);
4010 : : }
4011 : : }
4012 : :
3989 heikki.linnakangas@i 4013 : 67 : FreeDir(xldir);
4014 : 67 : }
4015 : :
4016 : : /*
4017 : : * Recycle or remove a log file that's no longer needed.
4018 : : *
4019 : : * segment_de is the dirent structure of the segment to recycle or remove.
4020 : : * recycleSegNo is the segment number to recycle up to. endlogSegNo is
4021 : : * the segment number of the current (or recent) end of WAL.
4022 : : *
4023 : : * endlogSegNo gets incremented if the segment is recycled so as it is not
4024 : : * checked again with future callers of this function.
4025 : : *
4026 : : * insertTLI is the current timeline for XLOG insertion. Any recycled segments
4027 : : * should be used for this timeline.
4028 : : */
4029 : : static void
1290 michael@paquier.xyz 4030 : 2612 : RemoveXlogFile(const struct dirent *segment_de,
4031 : : XLogSegNo recycleSegNo, XLogSegNo *endlogSegNo,
4032 : : TimeLineID insertTLI)
4033 : : {
4034 : : char path[MAXPGPATH];
4035 : : #ifdef WIN32
4036 : : char newpath[MAXPGPATH];
4037 : : #endif
4038 : 2612 : const char *segname = segment_de->d_name;
4039 : :
3989 heikki.linnakangas@i 4040 : 2612 : snprintf(path, MAXPGPATH, XLOGDIR "/%s", segname);
4041 : :
4042 : : /*
4043 : : * Before deleting the file, see if it can be recycled as a future log
4044 : : * segment. Only recycle normal files, because we don't want to recycle
4045 : : * symbolic links pointing to a separate archive directory.
4046 : : */
2539 tmunro@postgresql.or 4047 [ + - ]: 2612 : if (wal_recycle &&
1885 michael@paquier.xyz 4048 [ + + ]: 2612 : *endlogSegNo <= recycleSegNo &&
1721 noah@leadboat.com 4049 [ + + + - ]: 3613 : XLogCtl->InstallXLogFileSegmentActive && /* callee rechecks this */
1290 michael@paquier.xyz 4050 [ + + ]: 3284 : get_dirent_type(path, segment_de, false, DEBUG2) == PGFILETYPE_REG &&
1885 4051 : 1642 : InstallXLogFileSegment(endlogSegNo, path,
4052 : : true, recycleSegNo, insertTLI))
4053 : : {
3989 heikki.linnakangas@i 4054 [ + + ]: 1422 : ereport(DEBUG2,
4055 : : (errmsg_internal("recycled write-ahead log file \"%s\"",
4056 : : segname)));
4057 : 1422 : CheckpointStats.ckpt_segs_recycled++;
4058 : : /* Needn't recheck that slot on future iterations */
1885 michael@paquier.xyz 4059 : 1422 : (*endlogSegNo)++;
4060 : : }
4061 : : else
4062 : : {
4063 : : /* No need for any more future segments, or recycling failed ... */
4064 : : int rc;
4065 : :
3989 heikki.linnakangas@i 4066 [ + + ]: 1190 : ereport(DEBUG2,
4067 : : (errmsg_internal("removing write-ahead log file \"%s\"",
4068 : : segname)));
4069 : :
4070 : : #ifdef WIN32
4071 : :
4072 : : /*
4073 : : * On Windows, if another process (e.g another backend) holds the file
4074 : : * open in FILE_SHARE_DELETE mode, unlink will succeed, but the file
4075 : : * will still show up in directory listing until the last handle is
4076 : : * closed. To avoid confusing the lingering deleted file for a live
4077 : : * WAL file that needs to be archived, rename it before deleting it.
4078 : : *
4079 : : * If another process holds the file open without FILE_SHARE_DELETE
4080 : : * flag, rename will fail. We'll try again at the next checkpoint.
4081 : : */
4082 : : snprintf(newpath, MAXPGPATH, "%s.deleted", path);
4083 : : if (rename(path, newpath) != 0)
4084 : : {
4085 : : ereport(LOG,
4086 : : (errcode_for_file_access(),
4087 : : errmsg("could not rename file \"%s\": %m",
4088 : : path)));
4089 : : return;
4090 : : }
4091 : : rc = durable_unlink(newpath, LOG);
4092 : : #else
3275 teodor@sigaev.ru 4093 : 1190 : rc = durable_unlink(path, LOG);
4094 : : #endif
3989 heikki.linnakangas@i 4095 [ - + ]: 1190 : if (rc != 0)
4096 : : {
4097 : : /* Message already logged by durable_unlink() */
3989 heikki.linnakangas@i 4098 :UBC 0 : return;
4099 : : }
3989 heikki.linnakangas@i 4100 :CBC 1190 : CheckpointStats.ckpt_segs_removed++;
4101 : : }
4102 : :
4103 : 2612 : XLogArchiveCleanup(segname);
4104 : : }
4105 : :
4106 : : /*
4107 : : * Verify whether pg_wal, pg_wal/archive_status, and pg_wal/summaries exist.
4108 : : * If the latter do not exist, recreate them.
4109 : : *
4110 : : * It is not the goal of this function to verify the contents of these
4111 : : * directories, but to help in cases where someone has performed a cluster
4112 : : * copy for PITR purposes but omitted pg_wal from the copy.
4113 : : *
4114 : : * We could also recreate pg_wal if it doesn't exist, but a deliberate
4115 : : * policy decision was made not to. It is fairly common for pg_wal to be
4116 : : * a symlink, and if that was the DBA's intent then automatically making a
4117 : : * plain directory would result in degraded performance with no notice.
4118 : : */
4119 : : static void
6335 tgl@sss.pgh.pa.us 4120 : 1004 : ValidateXLOGDirectoryStructure(void)
4121 : : {
4122 : : char path[MAXPGPATH];
4123 : : struct stat stat_buf;
4124 : :
4125 : : /* Check for pg_wal; if it doesn't exist, error out */
4126 [ + - ]: 1004 : if (stat(XLOGDIR, &stat_buf) != 0 ||
4127 [ - + ]: 1004 : !S_ISDIR(stat_buf.st_mode))
6121 bruce@momjian.us 4128 [ # # ]:UBC 0 : ereport(FATAL,
4129 : : (errcode_for_file_access(),
4130 : : errmsg("required WAL directory \"%s\" does not exist",
4131 : : XLOGDIR)));
4132 : :
4133 : : /* Check for archive_status */
6335 tgl@sss.pgh.pa.us 4134 :CBC 1004 : snprintf(path, MAXPGPATH, XLOGDIR "/archive_status");
4135 [ + + ]: 1004 : if (stat(path, &stat_buf) == 0)
4136 : : {
4137 : : /* Check for weird cases where it exists but isn't a directory */
4138 [ - + ]: 1003 : if (!S_ISDIR(stat_buf.st_mode))
6121 bruce@momjian.us 4139 [ # # ]:UBC 0 : ereport(FATAL,
4140 : : (errcode_for_file_access(),
4141 : : errmsg("required WAL directory \"%s\" does not exist",
4142 : : path)));
4143 : : }
4144 : : else
4145 : : {
6335 tgl@sss.pgh.pa.us 4146 [ + - ]:CBC 1 : ereport(LOG,
4147 : : (errmsg("creating missing WAL directory \"%s\"", path)));
2899 sfrost@snowman.net 4148 [ - + ]: 1 : if (MakePGDirectory(path) < 0)
6121 bruce@momjian.us 4149 [ # # ]:UBC 0 : ereport(FATAL,
4150 : : (errcode_for_file_access(),
4151 : : errmsg("could not create missing directory \"%s\": %m",
4152 : : path)));
4153 : : }
4154 : :
4155 : : /* Check for summaries */
816 rhaas@postgresql.org 4156 :CBC 1004 : snprintf(path, MAXPGPATH, XLOGDIR "/summaries");
4157 [ + + ]: 1004 : if (stat(path, &stat_buf) == 0)
4158 : : {
4159 : : /* Check for weird cases where it exists but isn't a directory */
4160 [ - + ]: 1003 : if (!S_ISDIR(stat_buf.st_mode))
816 rhaas@postgresql.org 4161 [ # # ]:UBC 0 : ereport(FATAL,
4162 : : (errmsg("required WAL directory \"%s\" does not exist",
4163 : : path)));
4164 : : }
4165 : : else
4166 : : {
816 rhaas@postgresql.org 4167 [ + - ]:CBC 1 : ereport(LOG,
4168 : : (errmsg("creating missing WAL directory \"%s\"", path)));
4169 [ - + ]: 1 : if (MakePGDirectory(path) < 0)
816 rhaas@postgresql.org 4170 [ # # ]:UBC 0 : ereport(FATAL,
4171 : : (errmsg("could not create missing directory \"%s\": %m",
4172 : : path)));
4173 : : }
6335 tgl@sss.pgh.pa.us 4174 :CBC 1004 : }
4175 : :
4176 : : /*
4177 : : * Remove previous backup history files. This also retries creation of
4178 : : * .ready files for any backup history files for which XLogArchiveNotify
4179 : : * failed earlier.
4180 : : */
4181 : : static void
7206 4182 : 163 : CleanupBackupHistory(void)
4183 : : {
4184 : : DIR *xldir;
4185 : : struct dirent *xlde;
4186 : : char path[MAXPGPATH + sizeof(XLOGDIR)];
4187 : :
7559 4188 : 163 : xldir = AllocateDir(XLOGDIR);
4189 : :
4190 [ + + ]: 1668 : while ((xlde = ReadDir(xldir, XLOGDIR)) != NULL)
4191 : : {
3964 heikki.linnakangas@i 4192 [ + + ]: 1342 : if (IsBackupHistoryFileName(xlde->d_name))
4193 : : {
6397 tgl@sss.pgh.pa.us 4194 [ + + ]: 171 : if (XLogArchiveCheckDone(xlde->d_name))
4195 : : {
3229 peter_e@gmx.net 4196 [ + + ]: 137 : elog(DEBUG2, "removing WAL backup history file \"%s\"",
4197 : : xlde->d_name);
3260 4198 : 137 : snprintf(path, sizeof(path), XLOGDIR "/%s", xlde->d_name);
7578 bruce@momjian.us 4199 : 137 : unlink(path);
4200 : 137 : XLogArchiveCleanup(xlde->d_name);
4201 : : }
4202 : : }
4203 : : }
4204 : :
4205 : 163 : FreeDir(xldir);
4206 : 163 : }
4207 : :
4208 : : /*
4209 : : * I/O routines for pg_control
4210 : : *
4211 : : * *ControlFile is a buffer in shared memory that holds an image of the
4212 : : * contents of pg_control. WriteControlFile() initializes pg_control
4213 : : * given a preloaded buffer, ReadControlFile() loads the buffer from
4214 : : * the pg_control file (during postmaster or standalone-backend startup),
4215 : : * and UpdateControlFile() rewrites pg_control after we modify xlog state.
4216 : : * InitControlFile() fills the buffer with initial values.
4217 : : *
4218 : : * For simplicity, WriteControlFile() initializes the fields of pg_control
4219 : : * that are related to checking backend/database compatibility, and
4220 : : * ReadControlFile() verifies they are correct. We could split out the
4221 : : * I/O and compatibility-check functions, but there seems no need currently.
4222 : : */
4223 : :
4224 : : static void
600 peter@eisentraut.org 4225 : 51 : InitControlFile(uint64 sysidentifier, uint32 data_checksum_version)
4226 : : {
4227 : : char mock_auth_nonce[MOCK_AUTH_NONCE_LEN];
4228 : :
4229 : : /*
4230 : : * Generate a random nonce. This is used for authentication requests that
4231 : : * will fail because the user does not exist. The nonce is used to create
4232 : : * a genuine-looking password challenge for the non-existent user, in lieu
4233 : : * of an actual stored password.
4234 : : */
1488 heikki.linnakangas@i 4235 [ - + ]: 51 : if (!pg_strong_random(mock_auth_nonce, MOCK_AUTH_NONCE_LEN))
1488 heikki.linnakangas@i 4236 [ # # ]:UBC 0 : ereport(PANIC,
4237 : : (errcode(ERRCODE_INTERNAL_ERROR),
4238 : : errmsg("could not generate secret authorization token")));
4239 : :
1488 heikki.linnakangas@i 4240 :CBC 51 : memset(ControlFile, 0, sizeof(ControlFileData));
4241 : : /* Initialize pg_control status fields */
4242 : 51 : ControlFile->system_identifier = sysidentifier;
4243 : 51 : memcpy(ControlFile->mock_authentication_nonce, mock_auth_nonce, MOCK_AUTH_NONCE_LEN);
4244 : 51 : ControlFile->state = DB_SHUTDOWNED;
4245 : 51 : ControlFile->unloggedLSN = FirstNormalUnloggedLSN;
4246 : :
4247 : : /* Set important parameter values for use when replaying WAL */
2218 peter@eisentraut.org 4248 : 51 : ControlFile->MaxConnections = MaxConnections;
4249 : 51 : ControlFile->max_worker_processes = max_worker_processes;
4250 : 51 : ControlFile->max_wal_senders = max_wal_senders;
4251 : 51 : ControlFile->max_prepared_xacts = max_prepared_xacts;
4252 : 51 : ControlFile->max_locks_per_xact = max_locks_per_xact;
4253 : 51 : ControlFile->wal_level = wal_level;
4254 : 51 : ControlFile->wal_log_hints = wal_log_hints;
4255 : 51 : ControlFile->track_commit_timestamp = track_commit_timestamp;
600 4256 : 51 : ControlFile->data_checksum_version = data_checksum_version;
2218 4257 : 51 : }
4258 : :
4259 : : static void
9241 tgl@sss.pgh.pa.us 4260 : 51 : WriteControlFile(void)
4261 : : {
4262 : : int fd;
4263 : : char buffer[PG_CONTROL_FILE_SIZE]; /* need not be aligned */
4264 : :
4265 : : /*
4266 : : * Initialize version and compatibility-check fields
4267 : : */
9133 4268 : 51 : ControlFile->pg_control_version = PG_CONTROL_VERSION;
4269 : 51 : ControlFile->catalog_version_no = CATALOG_VERSION_NO;
4270 : :
7468 4271 : 51 : ControlFile->maxAlign = MAXIMUM_ALIGNOF;
4272 : 51 : ControlFile->floatFormat = FLOATFORMAT_VALUE;
4273 : :
9241 4274 : 51 : ControlFile->blcksz = BLCKSZ;
4275 : 51 : ControlFile->relseg_size = RELSEG_SIZE;
125 heikki.linnakangas@i 4276 :GNC 51 : ControlFile->slru_pages_per_segment = SLRU_PAGES_PER_SEGMENT;
7286 tgl@sss.pgh.pa.us 4277 :CBC 51 : ControlFile->xlog_blcksz = XLOG_BLCKSZ;
3099 andres@anarazel.de 4278 : 51 : ControlFile->xlog_seg_size = wal_segment_size;
4279 : :
8729 lockhart@fourpalms.o 4280 : 51 : ControlFile->nameDataLen = NAMEDATALEN;
7656 tgl@sss.pgh.pa.us 4281 : 51 : ControlFile->indexMaxKeys = INDEX_MAX_KEYS;
4282 : :
6921 4283 : 51 : ControlFile->toast_max_chunk_size = TOAST_MAX_CHUNK_SIZE;
4301 4284 : 51 : ControlFile->loblksize = LOBLKSIZE;
4285 : :
214 tgl@sss.pgh.pa.us 4286 :GNC 51 : ControlFile->float8ByVal = true; /* vestigial */
4287 : :
4288 : : /*
4289 : : * Initialize the default 'char' signedness.
4290 : : *
4291 : : * The signedness of the char type is implementation-defined. For instance
4292 : : * on x86 architecture CPUs, the char data type is typically treated as
4293 : : * signed by default, whereas on aarch architecture CPUs, it is typically
4294 : : * treated as unsigned by default. In v17 or earlier, we accidentally let
4295 : : * C implementation signedness affect persistent data. This led to
4296 : : * inconsistent results when comparing char data across different
4297 : : * platforms.
4298 : : *
4299 : : * This flag can be used as a hint to ensure consistent behavior for
4300 : : * pre-v18 data files that store data sorted by the 'char' type on disk,
4301 : : * especially in cross-platform replication scenarios.
4302 : : *
4303 : : * Newly created database clusters unconditionally set the default char
4304 : : * signedness to true. pg_upgrade changes this flag for clusters that were
4305 : : * initialized on signedness=false platforms. As a result,
4306 : : * signedness=false setting will become rare over time. If we had known
4307 : : * about this problem during the last development cycle that forced initdb
4308 : : * (v8.3), we would have made all clusters signed or all clusters
4309 : : * unsigned. Making pg_upgrade the only source of signedness=false will
4310 : : * cause the population of database clusters to converge toward that
4311 : : * retrospective ideal.
4312 : : */
387 msawada@postgresql.o 4313 :CBC 51 : ControlFile->default_char_signedness = true;
4314 : :
4315 : : /* Contents are protected with a CRC */
4149 heikki.linnakangas@i 4316 : 51 : INIT_CRC32C(ControlFile->crc);
4317 : 51 : COMP_CRC32C(ControlFile->crc,
4318 : : ControlFile,
4319 : : offsetof(ControlFileData, crc));
4320 : 51 : FIN_CRC32C(ControlFile->crc);
4321 : :
4322 : : /*
4323 : : * We write out PG_CONTROL_FILE_SIZE bytes into pg_control, zero-padding
4324 : : * the excess over sizeof(ControlFileData). This reduces the odds of
4325 : : * premature-EOF errors when reading pg_control. We'll still fail when we
4326 : : * check the contents of the file, but hopefully with a more specific
4327 : : * error than "couldn't read pg_control".
4328 : : */
3161 tgl@sss.pgh.pa.us 4329 : 51 : memset(buffer, 0, PG_CONTROL_FILE_SIZE);
9241 4330 : 51 : memcpy(buffer, ControlFile, sizeof(ControlFileData));
4331 : :
7559 4332 : 51 : fd = BasicOpenFile(XLOG_CONTROL_FILE,
4333 : : O_RDWR | O_CREAT | O_EXCL | PG_BINARY);
9241 4334 [ - + ]: 51 : if (fd < 0)
8273 tgl@sss.pgh.pa.us 4335 [ # # ]:UBC 0 : ereport(PANIC,
4336 : : (errcode_for_file_access(),
4337 : : errmsg("could not create file \"%s\": %m",
4338 : : XLOG_CONTROL_FILE)));
4339 : :
9048 tgl@sss.pgh.pa.us 4340 :CBC 51 : errno = 0;
3284 rhaas@postgresql.org 4341 : 51 : pgstat_report_wait_start(WAIT_EVENT_CONTROL_FILE_WRITE);
3161 tgl@sss.pgh.pa.us 4342 [ - + ]: 51 : if (write(fd, buffer, PG_CONTROL_FILE_SIZE) != PG_CONTROL_FILE_SIZE)
4343 : : {
4344 : : /* if write didn't set errno, assume problem is no disk space */
9048 tgl@sss.pgh.pa.us 4345 [ # # ]:UBC 0 : if (errno == 0)
4346 : 0 : errno = ENOSPC;
8273 4347 [ # # ]: 0 : ereport(PANIC,
4348 : : (errcode_for_file_access(),
4349 : : errmsg("could not write to file \"%s\": %m",
4350 : : XLOG_CONTROL_FILE)));
4351 : : }
3284 rhaas@postgresql.org 4352 :CBC 51 : pgstat_report_wait_end();
4353 : :
4354 : 51 : pgstat_report_wait_start(WAIT_EVENT_CONTROL_FILE_SYNC);
9228 tgl@sss.pgh.pa.us 4355 [ - + ]: 51 : if (pg_fsync(fd) != 0)
8273 tgl@sss.pgh.pa.us 4356 [ # # ]:UBC 0 : ereport(PANIC,
4357 : : (errcode_for_file_access(),
4358 : : errmsg("could not fsync file \"%s\": %m",
4359 : : XLOG_CONTROL_FILE)));
3284 rhaas@postgresql.org 4360 :CBC 51 : pgstat_report_wait_end();
4361 : :
2444 peter@eisentraut.org 4362 [ - + ]: 51 : if (close(fd) != 0)
8084 tgl@sss.pgh.pa.us 4363 [ # # ]:UBC 0 : ereport(PANIC,
4364 : : (errcode_for_file_access(),
4365 : : errmsg("could not close file \"%s\": %m",
4366 : : XLOG_CONTROL_FILE)));
9241 tgl@sss.pgh.pa.us 4367 :CBC 51 : }
4368 : :
4369 : : static void
4370 : 1056 : ReadControlFile(void)
4371 : : {
4372 : : pg_crc32c crc;
4373 : : int fd;
4374 : : char wal_segsz_str[20];
4375 : : int r;
4376 : :
4377 : : /*
4378 : : * Read data...
4379 : : */
7559 4380 : 1056 : fd = BasicOpenFile(XLOG_CONTROL_FILE,
4381 : : O_RDWR | PG_BINARY);
9241 4382 [ - + ]: 1056 : if (fd < 0)
8273 tgl@sss.pgh.pa.us 4383 [ # # ]:UBC 0 : ereport(PANIC,
4384 : : (errcode_for_file_access(),
4385 : : errmsg("could not open file \"%s\": %m",
4386 : : XLOG_CONTROL_FILE)));
4387 : :
3284 rhaas@postgresql.org 4388 :CBC 1056 : pgstat_report_wait_start(WAIT_EVENT_CONTROL_FILE_READ);
2858 magnus@hagander.net 4389 : 1056 : r = read(fd, ControlFile, sizeof(ControlFileData));
4390 [ - + ]: 1056 : if (r != sizeof(ControlFileData))
4391 : : {
2858 magnus@hagander.net 4392 [ # # ]:UBC 0 : if (r < 0)
4393 [ # # ]: 0 : ereport(PANIC,
4394 : : (errcode_for_file_access(),
4395 : : errmsg("could not read file \"%s\": %m",
4396 : : XLOG_CONTROL_FILE)));
4397 : : else
4398 [ # # ]: 0 : ereport(PANIC,
4399 : : (errcode(ERRCODE_DATA_CORRUPTED),
4400 : : errmsg("could not read file \"%s\": read %d of %zu",
4401 : : XLOG_CONTROL_FILE, r, sizeof(ControlFileData))));
4402 : : }
3284 rhaas@postgresql.org 4403 :CBC 1056 : pgstat_report_wait_end();
4404 : :
9241 tgl@sss.pgh.pa.us 4405 : 1056 : close(fd);
4406 : :
4407 : : /*
4408 : : * Check for expected pg_control format version. If this is wrong, the
4409 : : * CRC check will likely fail because we'll be checking the wrong number
4410 : : * of bytes. Complaining about wrong version will probably be more
4411 : : * enlightening than complaining about wrong CRC.
4412 : : */
4413 : :
6628 peter_e@gmx.net 4414 [ - + - - : 1056 : if (ControlFile->pg_control_version != PG_CONTROL_VERSION && ControlFile->pg_control_version % 65536 == 0 && ControlFile->pg_control_version / 65536 != 0)
- - ]
6628 peter_e@gmx.net 4415 [ # # ]:UBC 0 : ereport(FATAL,
4416 : : (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
4417 : : errmsg("database files are incompatible with server"),
4418 : : errdetail("The database cluster was initialized with PG_CONTROL_VERSION %d (0x%08x),"
4419 : : " but the server was compiled with PG_CONTROL_VERSION %d (0x%08x).",
4420 : : ControlFile->pg_control_version, ControlFile->pg_control_version,
4421 : : PG_CONTROL_VERSION, PG_CONTROL_VERSION),
4422 : : errhint("This could be a problem of mismatched byte ordering. It looks like you need to initdb.")));
4423 : :
9133 tgl@sss.pgh.pa.us 4424 [ - + ]:CBC 1056 : if (ControlFile->pg_control_version != PG_CONTROL_VERSION)
8273 tgl@sss.pgh.pa.us 4425 [ # # ]:UBC 0 : ereport(FATAL,
4426 : : (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
4427 : : errmsg("database files are incompatible with server"),
4428 : : errdetail("The database cluster was initialized with PG_CONTROL_VERSION %d,"
4429 : : " but the server was compiled with PG_CONTROL_VERSION %d.",
4430 : : ControlFile->pg_control_version, PG_CONTROL_VERSION),
4431 : : errhint("It looks like you need to initdb.")));
4432 : :
4433 : : /* Now check the CRC. */
4149 heikki.linnakangas@i 4434 :CBC 1056 : INIT_CRC32C(crc);
4435 : 1056 : COMP_CRC32C(crc,
4436 : : ControlFile,
4437 : : offsetof(ControlFileData, crc));
4438 : 1056 : FIN_CRC32C(crc);
4439 : :
4440 [ - + ]: 1056 : if (!EQ_CRC32C(crc, ControlFile->crc))
8273 tgl@sss.pgh.pa.us 4441 [ # # ]:UBC 0 : ereport(FATAL,
4442 : : (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
4443 : : errmsg("incorrect checksum in control file")));
4444 : :
4445 : : /*
4446 : : * Do compatibility checking immediately. If the database isn't
4447 : : * compatible with the backend executable, we want to abort before we can
4448 : : * possibly do any damage.
4449 : : */
9133 tgl@sss.pgh.pa.us 4450 [ - + ]:CBC 1056 : if (ControlFile->catalog_version_no != CATALOG_VERSION_NO)
8273 tgl@sss.pgh.pa.us 4451 [ # # ]:UBC 0 : ereport(FATAL,
4452 : : (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
4453 : : errmsg("database files are incompatible with server"),
4454 : : /* translator: %s is a variable name and %d is its value */
4455 : : errdetail("The database cluster was initialized with %s %d,"
4456 : : " but the server was compiled with %s %d.",
4457 : : "CATALOG_VERSION_NO", ControlFile->catalog_version_no,
4458 : : "CATALOG_VERSION_NO", CATALOG_VERSION_NO),
4459 : : errhint("It looks like you need to initdb.")));
7468 tgl@sss.pgh.pa.us 4460 [ - + ]:CBC 1056 : if (ControlFile->maxAlign != MAXIMUM_ALIGNOF)
7468 tgl@sss.pgh.pa.us 4461 [ # # ]:UBC 0 : ereport(FATAL,
4462 : : (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
4463 : : errmsg("database files are incompatible with server"),
4464 : : /* translator: %s is a variable name and %d is its value */
4465 : : errdetail("The database cluster was initialized with %s %d,"
4466 : : " but the server was compiled with %s %d.",
4467 : : "MAXALIGN", ControlFile->maxAlign,
4468 : : "MAXALIGN", MAXIMUM_ALIGNOF),
4469 : : errhint("It looks like you need to initdb.")));
7468 tgl@sss.pgh.pa.us 4470 [ - + ]:CBC 1056 : if (ControlFile->floatFormat != FLOATFORMAT_VALUE)
7468 tgl@sss.pgh.pa.us 4471 [ # # ]:UBC 0 : ereport(FATAL,
4472 : : (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
4473 : : errmsg("database files are incompatible with server"),
4474 : : errdetail("The database cluster appears to use a different floating-point number format than the server executable."),
4475 : : errhint("It looks like you need to initdb.")));
9241 tgl@sss.pgh.pa.us 4476 [ - + ]:CBC 1056 : if (ControlFile->blcksz != BLCKSZ)
8273 tgl@sss.pgh.pa.us 4477 [ # # ]:UBC 0 : ereport(FATAL,
4478 : : (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
4479 : : errmsg("database files are incompatible with server"),
4480 : : /* translator: %s is a variable name and %d is its value */
4481 : : errdetail("The database cluster was initialized with %s %d,"
4482 : : " but the server was compiled with %s %d.",
4483 : : "BLCKSZ", ControlFile->blcksz,
4484 : : "BLCKSZ", BLCKSZ),
4485 : : errhint("It looks like you need to recompile or initdb.")));
9241 tgl@sss.pgh.pa.us 4486 [ - + ]:CBC 1056 : if (ControlFile->relseg_size != RELSEG_SIZE)
8273 tgl@sss.pgh.pa.us 4487 [ # # ]:UBC 0 : ereport(FATAL,
4488 : : (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
4489 : : errmsg("database files are incompatible with server"),
4490 : : /* translator: %s is a variable name and %d is its value */
4491 : : errdetail("The database cluster was initialized with %s %d,"
4492 : : " but the server was compiled with %s %d.",
4493 : : "RELSEG_SIZE", ControlFile->relseg_size,
4494 : : "RELSEG_SIZE", RELSEG_SIZE),
4495 : : errhint("It looks like you need to recompile or initdb.")));
125 heikki.linnakangas@i 4496 [ - + ]:GNC 1056 : if (ControlFile->slru_pages_per_segment != SLRU_PAGES_PER_SEGMENT)
125 heikki.linnakangas@i 4497 [ # # ]:UNC 0 : ereport(FATAL,
4498 : : (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
4499 : : errmsg("database files are incompatible with server"),
4500 : : /* translator: %s is a variable name and %d is its value */
4501 : : errdetail("The database cluster was initialized with %s %d,"
4502 : : " but the server was compiled with %s %d.",
4503 : : "SLRU_PAGES_PER_SEGMENT", ControlFile->slru_pages_per_segment,
4504 : : "SLRU_PAGES_PER_SEGMENT", SLRU_PAGES_PER_SEGMENT),
4505 : : errhint("It looks like you need to recompile or initdb.")));
7286 tgl@sss.pgh.pa.us 4506 [ - + ]:CBC 1056 : if (ControlFile->xlog_blcksz != XLOG_BLCKSZ)
7286 tgl@sss.pgh.pa.us 4507 [ # # ]:UBC 0 : ereport(FATAL,
4508 : : (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
4509 : : errmsg("database files are incompatible with server"),
4510 : : /* translator: %s is a variable name and %d is its value */
4511 : : errdetail("The database cluster was initialized with %s %d,"
4512 : : " but the server was compiled with %s %d.",
4513 : : "XLOG_BLCKSZ", ControlFile->xlog_blcksz,
4514 : : "XLOG_BLCKSZ", XLOG_BLCKSZ),
4515 : : errhint("It looks like you need to recompile or initdb.")));
8729 lockhart@fourpalms.o 4516 [ - + ]:CBC 1056 : if (ControlFile->nameDataLen != NAMEDATALEN)
8273 tgl@sss.pgh.pa.us 4517 [ # # ]:UBC 0 : ereport(FATAL,
4518 : : (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
4519 : : errmsg("database files are incompatible with server"),
4520 : : /* translator: %s is a variable name and %d is its value */
4521 : : errdetail("The database cluster was initialized with %s %d,"
4522 : : " but the server was compiled with %s %d.",
4523 : : "NAMEDATALEN", ControlFile->nameDataLen,
4524 : : "NAMEDATALEN", NAMEDATALEN),
4525 : : errhint("It looks like you need to recompile or initdb.")));
7656 tgl@sss.pgh.pa.us 4526 [ - + ]:CBC 1056 : if (ControlFile->indexMaxKeys != INDEX_MAX_KEYS)
8273 tgl@sss.pgh.pa.us 4527 [ # # ]:UBC 0 : ereport(FATAL,
4528 : : (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
4529 : : errmsg("database files are incompatible with server"),
4530 : : /* translator: %s is a variable name and %d is its value */
4531 : : errdetail("The database cluster was initialized with %s %d,"
4532 : : " but the server was compiled with %s %d.",
4533 : : "INDEX_MAX_KEYS", ControlFile->indexMaxKeys,
4534 : : "INDEX_MAX_KEYS", INDEX_MAX_KEYS),
4535 : : errhint("It looks like you need to recompile or initdb.")));
6921 tgl@sss.pgh.pa.us 4536 [ - + ]:CBC 1056 : if (ControlFile->toast_max_chunk_size != TOAST_MAX_CHUNK_SIZE)
6921 tgl@sss.pgh.pa.us 4537 [ # # ]:UBC 0 : ereport(FATAL,
4538 : : (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
4539 : : errmsg("database files are incompatible with server"),
4540 : : /* translator: %s is a variable name and %d is its value */
4541 : : errdetail("The database cluster was initialized with %s %d,"
4542 : : " but the server was compiled with %s %d.",
4543 : : "TOAST_MAX_CHUNK_SIZE", ControlFile->toast_max_chunk_size,
4544 : : "TOAST_MAX_CHUNK_SIZE", (int) TOAST_MAX_CHUNK_SIZE),
4545 : : errhint("It looks like you need to recompile or initdb.")));
4301 tgl@sss.pgh.pa.us 4546 [ - + ]:CBC 1056 : if (ControlFile->loblksize != LOBLKSIZE)
4301 tgl@sss.pgh.pa.us 4547 [ # # ]:UBC 0 : ereport(FATAL,
4548 : : (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
4549 : : errmsg("database files are incompatible with server"),
4550 : : /* translator: %s is a variable name and %d is its value */
4551 : : errdetail("The database cluster was initialized with %s %d,"
4552 : : " but the server was compiled with %s %d.",
4553 : : "LOBLKSIZE", ControlFile->loblksize,
4554 : : "LOBLKSIZE", (int) LOBLKSIZE),
4555 : : errhint("It looks like you need to recompile or initdb.")));
4556 : :
214 tgl@sss.pgh.pa.us 4557 [ - + ]:GNC 1056 : Assert(ControlFile->float8ByVal); /* vestigial, not worth an error msg */
4558 : :
3099 andres@anarazel.de 4559 :CBC 1056 : wal_segment_size = ControlFile->xlog_seg_size;
4560 : :
4561 [ + - + - : 1056 : if (!IsValidWalSegSize(wal_segment_size))
+ - - + ]
3099 andres@anarazel.de 4562 [ # # ]:UBC 0 : ereport(ERROR, (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
4563 : : errmsg_plural("invalid WAL segment size in control file (%d byte)",
4564 : : "invalid WAL segment size in control file (%d bytes)",
4565 : : wal_segment_size,
4566 : : wal_segment_size),
4567 : : errdetail("The WAL segment size must be a power of two between 1 MB and 1 GB.")));
4568 : :
3099 andres@anarazel.de 4569 :CBC 1056 : snprintf(wal_segsz_str, sizeof(wal_segsz_str), "%d", wal_segment_size);
4570 : 1056 : SetConfigOption("wal_segment_size", wal_segsz_str, PGC_INTERNAL,
4571 : : PGC_S_DYNAMIC_DEFAULT);
4572 : :
4573 : : /* check and update variables dependent on wal_segment_size */
4574 [ - + ]: 1056 : if (ConvertToXSegs(min_wal_size_mb, wal_segment_size) < 2)
3099 andres@anarazel.de 4575 [ # # ]:UBC 0 : ereport(ERROR, (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
4576 : : /* translator: both %s are GUC names */
4577 : : errmsg("\"%s\" must be at least twice \"%s\"",
4578 : : "min_wal_size", "wal_segment_size")));
4579 : :
3099 andres@anarazel.de 4580 [ - + ]:CBC 1056 : if (ConvertToXSegs(max_wal_size_mb, wal_segment_size) < 2)
3099 andres@anarazel.de 4581 [ # # ]:UBC 0 : ereport(ERROR, (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
4582 : : /* translator: both %s are GUC names */
4583 : : errmsg("\"%s\" must be at least twice \"%s\"",
4584 : : "max_wal_size", "wal_segment_size")));
4585 : :
3099 andres@anarazel.de 4586 :CBC 1056 : UsableBytesInSegment =
4587 : 1056 : (wal_segment_size / XLOG_BLCKSZ * UsableBytesInPage) -
4588 : : (SizeOfXLogLongPHD - SizeOfXLogShortPHD);
4589 : :
4590 : 1056 : CalculateCheckpointSegments();
4591 : :
4592 : : /* Make the initdb settings visible as GUC variables, too */
2897 magnus@hagander.net 4593 [ + + ]: 1056 : SetConfigOption("data_checksums", DataChecksumsEnabled() ? "yes" : "no",
4594 : : PGC_INTERNAL, PGC_S_DYNAMIC_DEFAULT);
9241 tgl@sss.pgh.pa.us 4595 : 1056 : }
4596 : :
4597 : : /*
4598 : : * Utility wrapper to update the control file. Note that the control
4599 : : * file gets flushed.
4600 : : */
4601 : : static void
4602 : 9693 : UpdateControlFile(void)
4603 : : {
2540 peter@eisentraut.org 4604 : 9693 : update_controlfile(DataDir, ControlFile, true);
9657 vadim4o@yahoo.com 4605 : 9693 : }
4606 : :
4607 : : /*
4608 : : * Returns the unique system identifier from control file.
4609 : : */
4610 : : uint64
5903 heikki.linnakangas@i 4611 : 1522 : GetSystemIdentifier(void)
4612 : : {
4613 [ - + ]: 1522 : Assert(ControlFile != NULL);
4614 : 1522 : return ControlFile->system_identifier;
4615 : : }
4616 : :
4617 : : /*
4618 : : * Returns the random nonce from control file.
4619 : : */
4620 : : char *
3295 4621 : 2 : GetMockAuthenticationNonce(void)
4622 : : {
4623 [ - + ]: 2 : Assert(ControlFile != NULL);
4624 : 2 : return ControlFile->mock_authentication_nonce;
4625 : : }
4626 : :
4627 : : /*
4628 : : * Are checksums enabled for data pages?
4629 : : */
4630 : : bool
2897 magnus@hagander.net 4631 : 2880039 : DataChecksumsEnabled(void)
4632 : : {
4741 simon@2ndQuadrant.co 4633 [ - + ]: 2880039 : Assert(ControlFile != NULL);
4702 4634 : 2880039 : return (ControlFile->data_checksum_version > 0);
4635 : : }
4636 : :
4637 : : /*
4638 : : * Return true if the cluster was initialized on a platform where the
4639 : : * default signedness of char is "signed". This function exists for code
4640 : : * that deals with pre-v18 data files that store data sorted by the 'char'
4641 : : * type on disk (e.g., GIN and GiST indexes). See the comments in
4642 : : * WriteControlFile() for details.
4643 : : */
4644 : : bool
387 msawada@postgresql.o 4645 : 4 : GetDefaultCharSignedness(void)
4646 : : {
4647 : 4 : return ControlFile->default_char_signedness;
4648 : : }
4649 : :
4650 : : /*
4651 : : * Returns a fake LSN for unlogged relations.
4652 : : *
4653 : : * Each call generates an LSN that is greater than any previous value
4654 : : * returned. The current counter value is saved and restored across clean
4655 : : * shutdowns, but like unlogged relations, does not survive a crash. This can
4656 : : * be used in lieu of real LSN values returned by XLogInsert, if you need an
4657 : : * LSN-like increasing sequence of numbers without writing any WAL.
4658 : : */
4659 : : XLogRecPtr
4780 heikki.linnakangas@i 4660 : 201447 : GetFakeLSNForUnloggedRel(void)
4661 : : {
745 nathan@postgresql.or 4662 : 201447 : return pg_atomic_fetch_add_u64(&XLogCtl->unloggedLSN, 1);
4663 : : }
4664 : :
4665 : : /*
4666 : : * Auto-tune the number of XLOG buffers.
4667 : : *
4668 : : * The preferred setting for wal_buffers is about 3% of shared_buffers, with
4669 : : * a maximum of one XLOG segment (there is little reason to think that more
4670 : : * is helpful, at least so long as we force an fsync when switching log files)
4671 : : * and a minimum of 8 blocks (which was the default value prior to PostgreSQL
4672 : : * 9.1, when auto-tuning was added).
4673 : : *
4674 : : * This should not be called until NBuffers has received its final value.
4675 : : */
4676 : : static int
5456 tgl@sss.pgh.pa.us 4677 : 1148 : XLOGChooseNumBuffers(void)
4678 : : {
4679 : : int xbuffers;
4680 : :
4681 : 1148 : xbuffers = NBuffers / 32;
3099 andres@anarazel.de 4682 [ + + ]: 1148 : if (xbuffers > (wal_segment_size / XLOG_BLCKSZ))
4683 : 24 : xbuffers = (wal_segment_size / XLOG_BLCKSZ);
5456 tgl@sss.pgh.pa.us 4684 [ + + ]: 1148 : if (xbuffers < 8)
4685 : 448 : xbuffers = 8;
4686 : 1148 : return xbuffers;
4687 : : }
4688 : :
4689 : : /*
4690 : : * GUC check_hook for wal_buffers
4691 : : */
4692 : : bool
4693 : 2332 : check_wal_buffers(int *newval, void **extra, GucSource source)
4694 : : {
4695 : : /*
4696 : : * -1 indicates a request for auto-tune.
4697 : : */
4698 [ + + ]: 2332 : if (*newval == -1)
4699 : : {
4700 : : /*
4701 : : * If we haven't yet changed the boot_val default of -1, just let it
4702 : : * be. We'll fix it when XLOGShmemSize is called.
4703 : : */
4704 [ + - ]: 1184 : if (XLOGbuffers == -1)
4705 : 1184 : return true;
4706 : :
4707 : : /* Otherwise, substitute the auto-tune value */
5456 tgl@sss.pgh.pa.us 4708 :UBC 0 : *newval = XLOGChooseNumBuffers();
4709 : : }
4710 : :
4711 : : /*
4712 : : * We clamp manually-set values to at least 4 blocks. Prior to PostgreSQL
4713 : : * 9.1, a minimum of 4 was enforced by guc.c, but since that is no longer
4714 : : * the case, we just silently treat such values as a request for the
4715 : : * minimum. (We could throw an error instead, but that doesn't seem very
4716 : : * helpful.)
4717 : : */
5456 tgl@sss.pgh.pa.us 4718 [ - + ]:CBC 1148 : if (*newval < 4)
5456 tgl@sss.pgh.pa.us 4719 :UBC 0 : *newval = 4;
4720 : :
5456 tgl@sss.pgh.pa.us 4721 :CBC 1148 : return true;
4722 : : }
4723 : :
4724 : : /*
4725 : : * GUC check_hook for wal_consistency_checking
4726 : : */
4727 : : bool
1279 4728 : 2164 : check_wal_consistency_checking(char **newval, void **extra, GucSource source)
4729 : : {
4730 : : char *rawstring;
4731 : : List *elemlist;
4732 : : ListCell *l;
4733 : : bool newwalconsistency[RM_MAX_ID + 1];
4734 : :
4735 : : /* Initialize the array */
4736 [ + - + - : 71412 : MemSet(newwalconsistency, 0, (RM_MAX_ID + 1) * sizeof(bool));
+ - + - +
+ ]
4737 : :
4738 : : /* Need a modifiable copy of string */
4739 : 2164 : rawstring = pstrdup(*newval);
4740 : :
4741 : : /* Parse string into list of identifiers */
4742 [ - + ]: 2164 : if (!SplitIdentifierString(rawstring, ',', &elemlist))
4743 : : {
4744 : : /* syntax error in list */
1279 tgl@sss.pgh.pa.us 4745 :UBC 0 : GUC_check_errdetail("List syntax is invalid.");
4746 : 0 : pfree(rawstring);
4747 : 0 : list_free(elemlist);
4748 : 0 : return false;
4749 : : }
4750 : :
1279 tgl@sss.pgh.pa.us 4751 [ + + + + :CBC 2657 : foreach(l, elemlist)
+ + ]
4752 : : {
4753 : 493 : char *tok = (char *) lfirst(l);
4754 : : int rmid;
4755 : :
4756 : : /* Check for 'all'. */
4757 [ + + ]: 493 : if (pg_strcasecmp(tok, "all") == 0)
4758 : : {
4759 [ + + ]: 126187 : for (rmid = 0; rmid <= RM_MAX_ID; rmid++)
4760 [ + + + + ]: 125696 : if (RmgrIdExists(rmid) && GetRmgr(rmid).rm_mask != NULL)
4761 : 4910 : newwalconsistency[rmid] = true;
4762 : : }
4763 : : else
4764 : : {
4765 : : /* Check if the token matches any known resource manager. */
4766 : 2 : bool found = false;
4767 : :
4768 [ + - ]: 36 : for (rmid = 0; rmid <= RM_MAX_ID; rmid++)
4769 : : {
4770 [ + - + + : 54 : if (RmgrIdExists(rmid) && GetRmgr(rmid).rm_mask != NULL &&
+ + ]
4771 : 18 : pg_strcasecmp(tok, GetRmgr(rmid).rm_name) == 0)
4772 : : {
4773 : 2 : newwalconsistency[rmid] = true;
4774 : 2 : found = true;
4775 : 2 : break;
4776 : : }
4777 : : }
4778 [ - + ]: 2 : if (!found)
4779 : : {
4780 : : /*
4781 : : * During startup, it might be a not-yet-loaded custom
4782 : : * resource manager. Defer checking until
4783 : : * InitializeWalConsistencyChecking().
4784 : : */
1279 tgl@sss.pgh.pa.us 4785 [ # # ]:UBC 0 : if (!process_shared_preload_libraries_done)
4786 : : {
4787 : 0 : check_wal_consistency_checking_deferred = true;
4788 : : }
4789 : : else
4790 : : {
4791 : 0 : GUC_check_errdetail("Unrecognized key word: \"%s\".", tok);
4792 : 0 : pfree(rawstring);
4793 : 0 : list_free(elemlist);
4794 : 0 : return false;
4795 : : }
4796 : : }
4797 : : }
4798 : : }
4799 : :
1279 tgl@sss.pgh.pa.us 4800 :CBC 2164 : pfree(rawstring);
4801 : 2164 : list_free(elemlist);
4802 : :
4803 : : /* assign new value */
353 dgustafsson@postgres 4804 : 2164 : *extra = guc_malloc(LOG, (RM_MAX_ID + 1) * sizeof(bool));
4805 [ - + ]: 2164 : if (!*extra)
353 dgustafsson@postgres 4806 :UBC 0 : return false;
1279 tgl@sss.pgh.pa.us 4807 :CBC 2164 : memcpy(*extra, newwalconsistency, (RM_MAX_ID + 1) * sizeof(bool));
4808 : 2164 : return true;
4809 : : }
4810 : :
4811 : : /*
4812 : : * GUC assign_hook for wal_consistency_checking
4813 : : */
4814 : : void
4815 : 2163 : assign_wal_consistency_checking(const char *newval, void *extra)
4816 : : {
4817 : : /*
4818 : : * If some checks were deferred, it's possible that the checks will fail
4819 : : * later during InitializeWalConsistencyChecking(). But in that case, the
4820 : : * postmaster will exit anyway, so it's safe to proceed with the
4821 : : * assignment.
4822 : : *
4823 : : * Any built-in resource managers specified are assigned immediately,
4824 : : * which affects WAL created before shared_preload_libraries are
4825 : : * processed. Any custom resource managers specified won't be assigned
4826 : : * until after shared_preload_libraries are processed, but that's OK
4827 : : * because WAL for a custom resource manager can't be written before the
4828 : : * module is loaded anyway.
4829 : : */
4830 : 2163 : wal_consistency_checking = extra;
4831 : 2163 : }
4832 : :
4833 : : /*
4834 : : * InitializeWalConsistencyChecking: run after loading custom resource managers
4835 : : *
4836 : : * If any unknown resource managers were specified in the
4837 : : * wal_consistency_checking GUC, processing was deferred. Now that
4838 : : * shared_preload_libraries have been loaded, process wal_consistency_checking
4839 : : * again.
4840 : : */
4841 : : void
4842 : 995 : InitializeWalConsistencyChecking(void)
4843 : : {
4844 [ - + ]: 995 : Assert(process_shared_preload_libraries_done);
4845 : :
4846 [ - + ]: 995 : if (check_wal_consistency_checking_deferred)
4847 : : {
4848 : : struct config_generic *guc;
4849 : :
1279 tgl@sss.pgh.pa.us 4850 :UBC 0 : guc = find_option("wal_consistency_checking", false, false, ERROR);
4851 : :
4852 : 0 : check_wal_consistency_checking_deferred = false;
4853 : :
4854 : 0 : set_config_option_ext("wal_consistency_checking",
4855 : : wal_consistency_checking_string,
4856 : : guc->scontext, guc->source, guc->srole,
4857 : : GUC_ACTION_SET, true, ERROR, false);
4858 : :
4859 : : /* checking should not be deferred again */
4860 [ # # ]: 0 : Assert(!check_wal_consistency_checking_deferred);
4861 : : }
1279 tgl@sss.pgh.pa.us 4862 :CBC 995 : }
4863 : :
4864 : : /*
4865 : : * GUC show_hook for archive_command
4866 : : */
4867 : : const char *
4868 : 1781 : show_archive_command(void)
4869 : : {
4870 [ + + - + : 1781 : if (XLogArchivingActive())
+ + ]
4871 : 2 : return XLogArchiveCommand;
4872 : : else
4873 : 1779 : return "(disabled)";
4874 : : }
4875 : :
4876 : : /*
4877 : : * GUC show_hook for in_hot_standby
4878 : : */
4879 : : const char *
4880 : 15945 : show_in_hot_standby(void)
4881 : : {
4882 : : /*
4883 : : * We display the actual state based on shared memory, so that this GUC
4884 : : * reports up-to-date state if examined intra-query. The underlying
4885 : : * variable (in_hot_standby_guc) changes only when we transmit a new value
4886 : : * to the client.
4887 : : */
4888 [ + + ]: 15945 : return RecoveryInProgress() ? "on" : "off";
4889 : : }
4890 : :
4891 : : /*
4892 : : * GUC show_hook for effective_wal_level
4893 : : */
4894 : : const char *
82 msawada@postgresql.o 4895 :GNC 1818 : show_effective_wal_level(void)
4896 : : {
4897 [ + + ]: 1818 : if (wal_level == WAL_LEVEL_MINIMAL)
4898 : 272 : return "minimal";
4899 : :
4900 : : /*
4901 : : * During recovery, effective_wal_level reflects the primary's
4902 : : * configuration rather than the local wal_level value.
4903 : : */
4904 [ + + ]: 1546 : if (RecoveryInProgress())
4905 [ + + ]: 22 : return IsXLogLogicalInfoEnabled() ? "logical" : "replica";
4906 : :
4907 [ + + + + ]: 1524 : return XLogLogicalInfoActive() ? "logical" : "replica";
4908 : : }
4909 : :
4910 : : /*
4911 : : * Read the control file, set respective GUCs.
4912 : : *
4913 : : * This is to be called during startup, including a crash recovery cycle,
4914 : : * unless in bootstrap mode, where no control file yet exists. As there's no
4915 : : * usable shared memory yet (its sizing can depend on the contents of the
4916 : : * control file!), first store the contents in local memory. XLOGShmemInit()
4917 : : * will then copy it to shared memory later.
4918 : : *
4919 : : * reset just controls whether previous contents are to be expected (in the
4920 : : * reset case, there's a dangling pointer into old shared memory), or not.
4921 : : */
4922 : : void
3101 andres@anarazel.de 4923 :CBC 1005 : LocalProcessControlFile(bool reset)
4924 : : {
4925 [ + + - + ]: 1005 : Assert(reset || ControlFile == NULL);
95 michael@paquier.xyz 4926 :GNC 1005 : ControlFile = palloc_object(ControlFileData);
3105 andres@anarazel.de 4927 :CBC 1005 : ReadControlFile();
4928 : 1005 : }
4929 : :
4930 : : /*
4931 : : * Get the wal_level from the control file. For a standby, this value should be
4932 : : * considered as its active wal_level, because it may be different from what
4933 : : * was originally configured on standby.
4934 : : */
4935 : : WalLevel
1072 andres@anarazel.de 4936 :LBC (69) : GetActiveWalLevelOnStandby(void)
4937 : : {
4938 : (69) : return ControlFile->wal_level;
4939 : : }
4940 : :
4941 : : /*
4942 : : * Initialization of shared memory for XLOG
4943 : : */
4944 : : Size
9245 peter_e@gmx.net 4945 :CBC 3297 : XLOGShmemSize(void)
4946 : : {
4947 : : Size size;
4948 : :
4949 : : /*
4950 : : * If the value of wal_buffers is -1, use the preferred auto-tune value.
4951 : : * This isn't an amazingly clean place to do this, but we must wait till
4952 : : * NBuffers has received its final value, and must do it before using the
4953 : : * value of XLOGbuffers to do anything important.
4954 : : *
4955 : : * We prefer to report this value's source as PGC_S_DYNAMIC_DEFAULT.
4956 : : * However, if the DBA explicitly set wal_buffers = -1 in the config file,
4957 : : * then PGC_S_DYNAMIC_DEFAULT will fail to override that and we must force
4958 : : * the matter with PGC_S_OVERRIDE.
4959 : : */
5456 tgl@sss.pgh.pa.us 4960 [ + + ]: 3297 : if (XLOGbuffers == -1)
4961 : : {
4962 : : char buf[32];
4963 : :
4964 : 1148 : snprintf(buf, sizeof(buf), "%d", XLOGChooseNumBuffers());
1376 4965 : 1148 : SetConfigOption("wal_buffers", buf, PGC_POSTMASTER,
4966 : : PGC_S_DYNAMIC_DEFAULT);
4967 [ - + ]: 1148 : if (XLOGbuffers == -1) /* failed to apply it? */
1376 tgl@sss.pgh.pa.us 4968 :UBC 0 : SetConfigOption("wal_buffers", buf, PGC_POSTMASTER,
4969 : : PGC_S_OVERRIDE);
4970 : : }
5531 tgl@sss.pgh.pa.us 4971 [ - + ]:CBC 3297 : Assert(XLOGbuffers > 0);
4972 : :
4973 : : /* XLogCtl */
7512 4974 : 3297 : size = sizeof(XLogCtlData);
4975 : :
4976 : : /* WAL insertion locks, plus alignment */
4183 heikki.linnakangas@i 4977 : 3297 : size = add_size(size, mul_size(sizeof(WALInsertLockPadded), NUM_XLOGINSERT_LOCKS + 1));
4978 : : /* xlblocks array */
817 jdavis@postgresql.or 4979 : 3297 : size = add_size(size, mul_size(sizeof(pg_atomic_uint64), XLOGbuffers));
4980 : : /* extra alignment padding for XLOG I/O buffers */
1072 tmunro@postgresql.or 4981 : 3297 : size = add_size(size, Max(XLOG_BLCKSZ, PG_IO_ALIGN_SIZE));
4982 : : /* and the buffers themselves */
7286 tgl@sss.pgh.pa.us 4983 : 3297 : size = add_size(size, mul_size(XLOG_BLCKSZ, XLOGbuffers));
4984 : :
4985 : : /*
4986 : : * Note: we don't count ControlFileData, it comes out of the "slop factor"
4987 : : * added by CreateSharedMemoryAndSemaphores. This lets us use this
4988 : : * routine again below to compute the actual allocation size.
4989 : : */
4990 : :
7512 4991 : 3297 : return size;
4992 : : }
4993 : :
4994 : : void
9657 vadim4o@yahoo.com 4995 : 1150 : XLOGShmemInit(void)
4996 : : {
4997 : : bool foundCFile,
4998 : : foundXLog;
4999 : : char *allocptr;
5000 : : int i;
5001 : : ControlFileData *localControlFile;
5002 : :
5003 : : #ifdef WAL_DEBUG
5004 : :
5005 : : /*
5006 : : * Create a memory context for WAL debugging that's exempt from the normal
5007 : : * "no pallocs in critical section" rule. Yes, that can lead to a PANIC if
5008 : : * an allocation fails, but wal_debug is not for production use anyway.
5009 : : */
5010 : : if (walDebugCxt == NULL)
5011 : : {
5012 : : walDebugCxt = AllocSetContextCreate(TopMemoryContext,
5013 : : "WAL Debug",
5014 : : ALLOCSET_DEFAULT_SIZES);
5015 : : MemoryContextAllowInCriticalSection(walDebugCxt, true);
5016 : : }
5017 : : #endif
5018 : :
5019 : :
3101 andres@anarazel.de 5020 : 1150 : XLogCtl = (XLogCtlData *)
5021 : 1150 : ShmemInitStruct("XLOG Ctl", XLOGShmemSize(), &foundXLog);
5022 : :
3105 5023 : 1150 : localControlFile = ControlFile;
9241 tgl@sss.pgh.pa.us 5024 : 1150 : ControlFile = (ControlFileData *)
8121 bruce@momjian.us 5025 : 1150 : ShmemInitStruct("Control File", sizeof(ControlFileData), &foundCFile);
5026 : :
7510 tgl@sss.pgh.pa.us 5027 [ + - - + ]: 1150 : if (foundCFile || foundXLog)
5028 : : {
5029 : : /* both should be present or neither */
7510 tgl@sss.pgh.pa.us 5030 [ # # # # ]:UBC 0 : Assert(foundCFile && foundXLog);
5031 : :
5032 : : /* Initialize local copy of WALInsertLocks */
4252 rhaas@postgresql.org 5033 : 0 : WALInsertLocks = XLogCtl->Insert.WALInsertLocks;
5034 : :
3101 andres@anarazel.de 5035 [ # # ]: 0 : if (localControlFile)
5036 : 0 : pfree(localControlFile);
8121 bruce@momjian.us 5037 : 0 : return;
5038 : : }
9133 tgl@sss.pgh.pa.us 5039 :CBC 1150 : memset(XLogCtl, 0, sizeof(XLogCtlData));
5040 : :
5041 : : /*
5042 : : * Already have read control file locally, unless in bootstrap mode. Move
5043 : : * contents into shared memory.
5044 : : */
3101 andres@anarazel.de 5045 [ + + ]: 1150 : if (localControlFile)
5046 : : {
5047 : 997 : memcpy(ControlFile, localControlFile, sizeof(ControlFileData));
5048 : 997 : pfree(localControlFile);
5049 : : }
5050 : :
5051 : : /*
5052 : : * Since XLogCtlData contains XLogRecPtr fields, its sizeof should be a
5053 : : * multiple of the alignment for same, so no extra alignment padding is
5054 : : * needed here.
5055 : : */
4633 heikki.linnakangas@i 5056 : 1150 : allocptr = ((char *) XLogCtl) + sizeof(XLogCtlData);
817 jdavis@postgresql.or 5057 : 1150 : XLogCtl->xlblocks = (pg_atomic_uint64 *) allocptr;
5058 : 1150 : allocptr += sizeof(pg_atomic_uint64) * XLOGbuffers;
5059 : :
5060 [ + + ]: 328899 : for (i = 0; i < XLOGbuffers; i++)
5061 : : {
5062 : 327749 : pg_atomic_init_u64(&XLogCtl->xlblocks[i], InvalidXLogRecPtr);
5063 : : }
5064 : :
5065 : : /* WAL insertion locks. Ensure they're aligned to the full padded size */
4377 heikki.linnakangas@i 5066 : 1150 : allocptr += sizeof(WALInsertLockPadded) -
3189 tgl@sss.pgh.pa.us 5067 : 1150 : ((uintptr_t) allocptr) % sizeof(WALInsertLockPadded);
4377 heikki.linnakangas@i 5068 : 1150 : WALInsertLocks = XLogCtl->Insert.WALInsertLocks =
5069 : : (WALInsertLockPadded *) allocptr;
4183 5070 : 1150 : allocptr += sizeof(WALInsertLockPadded) * NUM_XLOGINSERT_LOCKS;
5071 : :
5072 [ + + ]: 10350 : for (i = 0; i < NUM_XLOGINSERT_LOCKS; i++)
5073 : : {
3743 rhaas@postgresql.org 5074 : 9200 : LWLockInitialize(&WALInsertLocks[i].l.lock, LWTRANCHE_WAL_INSERT);
964 michael@paquier.xyz 5075 : 9200 : pg_atomic_init_u64(&WALInsertLocks[i].l.insertingAt, InvalidXLogRecPtr);
3370 andres@anarazel.de 5076 : 9200 : WALInsertLocks[i].l.lastImportantAt = InvalidXLogRecPtr;
5077 : : }
5078 : :
5079 : : /*
5080 : : * Align the start of the page buffers to a full xlog block size boundary.
5081 : : * This simplifies some calculations in XLOG insertion. It is also
5082 : : * required for O_DIRECT.
5083 : : */
4633 heikki.linnakangas@i 5084 : 1150 : allocptr = (char *) TYPEALIGN(XLOG_BLCKSZ, allocptr);
7512 tgl@sss.pgh.pa.us 5085 : 1150 : XLogCtl->pages = allocptr;
7286 5086 : 1150 : memset(XLogCtl->pages, 0, (Size) XLOG_BLCKSZ * XLOGbuffers);
5087 : :
5088 : : /*
5089 : : * Do basic initialization of XLogCtl shared data. (StartupXLOG will fill
5090 : : * in additional info.)
5091 : : */
9133 5092 : 1150 : XLogCtl->XLogCacheBlck = XLOGbuffers - 1;
2151 michael@paquier.xyz 5093 : 1150 : XLogCtl->SharedRecoveryState = RECOVERY_STATE_CRASH;
1721 noah@leadboat.com 5094 : 1150 : XLogCtl->InstallXLogFileSegmentActive = false;
5059 tgl@sss.pgh.pa.us 5095 : 1150 : XLogCtl->WalWriterSleeping = false;
5096 : :
4633 heikki.linnakangas@i 5097 : 1150 : SpinLockInit(&XLogCtl->Insert.insertpos_lck);
8933 tgl@sss.pgh.pa.us 5098 : 1150 : SpinLockInit(&XLogCtl->info_lck);
707 alvherre@alvh.no-ip. 5099 : 1150 : pg_atomic_init_u64(&XLogCtl->logInsertResult, InvalidXLogRecPtr);
709 5100 : 1150 : pg_atomic_init_u64(&XLogCtl->logWriteResult, InvalidXLogRecPtr);
5101 : 1150 : pg_atomic_init_u64(&XLogCtl->logFlushResult, InvalidXLogRecPtr);
745 nathan@postgresql.or 5102 : 1150 : pg_atomic_init_u64(&XLogCtl->unloggedLSN, InvalidXLogRecPtr);
5103 : : }
5104 : :
5105 : : /*
5106 : : * This func must be called ONCE on system install. It creates pg_control
5107 : : * and the initial XLOG segment.
5108 : : */
5109 : : void
600 peter@eisentraut.org 5110 : 51 : BootStrapXLOG(uint32 data_checksum_version)
5111 : : {
5112 : : CheckPoint checkPoint;
5113 : : PGAlignedXLogBlock buffer;
5114 : : XLogPageHeader page;
5115 : : XLogLongPageHeader longpage;
5116 : : XLogRecord *record;
5117 : : char *recptr;
5118 : : uint64 sysidentifier;
5119 : : struct timeval tv;
5120 : : pg_crc32c crc;
5121 : :
5122 : : /* allow ordinary WAL segment creation, like StartupXLOG() would */
1306 michael@paquier.xyz 5123 : 51 : SetInstallXLogFileSegmentActive();
5124 : :
5125 : : /*
5126 : : * Select a hopefully-unique system identifier code for this installation.
5127 : : * We use the result of gettimeofday(), including the fractional seconds
5128 : : * field, as being about as unique as we can easily get. (Think not to
5129 : : * use random(), since it hasn't been seeded and there's no portable way
5130 : : * to seed it other than the system clock value...) The upper half of the
5131 : : * uint64 value is just the tv_sec part, while the lower half contains the
5132 : : * tv_usec part (which must fit in 20 bits), plus 12 bits from our current
5133 : : * PID for a little extra uniqueness. A person knowing this encoding can
5134 : : * determine the initialization time of the installation, which could
5135 : : * perhaps be useful sometimes.
5136 : : */
8068 tgl@sss.pgh.pa.us 5137 : 51 : gettimeofday(&tv, NULL);
5138 : 51 : sysidentifier = ((uint64) tv.tv_sec) << 32;
4341 5139 : 51 : sysidentifier |= ((uint64) tv.tv_usec) << 12;
5140 : 51 : sysidentifier |= getpid() & 0xFFF;
5141 : :
97 peter@eisentraut.org 5142 :GNC 51 : memset(&buffer, 0, sizeof buffer);
5143 : 51 : page = (XLogPageHeader) &buffer;
5144 : :
5145 : : /*
5146 : : * Set up information for the initial checkpoint record
5147 : : *
5148 : : * The initial checkpoint record is written to the beginning of the WAL
5149 : : * segment with logid=0 logseg=1. The very first WAL segment, 0/0, is not
5150 : : * used, so that we can use 0/0 to mean "before any valid WAL segment".
5151 : : */
3099 andres@anarazel.de 5152 :CBC 51 : checkPoint.redo = wal_segment_size + SizeOfXLogLongPHD;
1591 rhaas@postgresql.org 5153 : 51 : checkPoint.ThisTimeLineID = BootstrapTimeLineID;
5154 : 51 : checkPoint.PrevTimeLineID = BootstrapTimeLineID;
5163 simon@2ndQuadrant.co 5155 : 51 : checkPoint.fullPageWrites = fullPageWrites;
82 msawada@postgresql.o 5156 :GNC 51 : checkPoint.logicalDecodingEnabled = (wal_level == WAL_LEVEL_LOGICAL);
601 rhaas@postgresql.org 5157 :CBC 51 : checkPoint.wal_level = wal_level;
5158 : : checkPoint.nextXid =
2544 tmunro@postgresql.or 5159 : 51 : FullTransactionIdFromEpochAndXid(0, FirstNormalTransactionId);
1704 tgl@sss.pgh.pa.us 5160 : 51 : checkPoint.nextOid = FirstGenbkiObjectId;
7626 5161 : 51 : checkPoint.nextMulti = FirstMultiXactId;
96 heikki.linnakangas@i 5162 :GNC 51 : checkPoint.nextMultiOffset = 1;
6040 tgl@sss.pgh.pa.us 5163 :CBC 51 : checkPoint.oldestXid = FirstNormalTransactionId;
1424 5164 : 51 : checkPoint.oldestXidDB = Template1DbOid;
4799 alvherre@alvh.no-ip. 5165 : 51 : checkPoint.oldestMulti = FirstMultiXactId;
1424 tgl@sss.pgh.pa.us 5166 : 51 : checkPoint.oldestMultiDB = Template1DbOid;
3730 mail@joeconway.com 5167 : 51 : checkPoint.oldestCommitTsXid = InvalidTransactionId;
5168 : 51 : checkPoint.newestCommitTsXid = InvalidTransactionId;
6601 tgl@sss.pgh.pa.us 5169 : 51 : checkPoint.time = (pg_time_t) time(NULL);
5930 simon@2ndQuadrant.co 5170 : 51 : checkPoint.oldestActiveXid = InvalidTransactionId;
5171 : :
828 heikki.linnakangas@i 5172 : 51 : TransamVariables->nextXid = checkPoint.nextXid;
5173 : 51 : TransamVariables->nextOid = checkPoint.nextOid;
5174 : 51 : TransamVariables->oidCount = 0;
7585 tgl@sss.pgh.pa.us 5175 : 51 : MultiXactSetNextMXact(checkPoint.nextMulti, checkPoint.nextMultiOffset);
3279 rhaas@postgresql.org 5176 : 51 : AdvanceOldestClogXid(checkPoint.oldestXid);
5870 tgl@sss.pgh.pa.us 5177 : 51 : SetTransactionIdLimit(checkPoint.oldestXid, checkPoint.oldestXidDB);
96 heikki.linnakangas@i 5178 :GNC 51 : SetMultiXactIdLimit(checkPoint.oldestMulti, checkPoint.oldestMultiDB);
4120 alvherre@alvh.no-ip. 5179 :CBC 51 : SetCommitTsLimit(InvalidTransactionId, InvalidTransactionId);
5180 : :
5181 : : /* Set up the XLOG page header */
9657 vadim4o@yahoo.com 5182 : 51 : page->xlp_magic = XLOG_PAGE_MAGIC;
7907 tgl@sss.pgh.pa.us 5183 : 51 : page->xlp_info = XLP_LONG_HEADER;
1591 rhaas@postgresql.org 5184 : 51 : page->xlp_tli = BootstrapTimeLineID;
3099 andres@anarazel.de 5185 : 51 : page->xlp_pageaddr = wal_segment_size;
7907 tgl@sss.pgh.pa.us 5186 : 51 : longpage = (XLogLongPageHeader) page;
5187 : 51 : longpage->xlp_sysid = sysidentifier;
3099 andres@anarazel.de 5188 : 51 : longpage->xlp_seg_size = wal_segment_size;
7284 tgl@sss.pgh.pa.us 5189 : 51 : longpage->xlp_xlog_blcksz = XLOG_BLCKSZ;
5190 : :
5191 : : /* Insert the initial checkpoint record */
4133 heikki.linnakangas@i 5192 : 51 : recptr = ((char *) page + SizeOfXLogLongPHD);
5193 : 51 : record = (XLogRecord *) recptr;
45 alvherre@kurilemu.de 5194 :GNC 51 : record->xl_prev = InvalidXLogRecPtr;
9657 vadim4o@yahoo.com 5195 :CBC 51 : record->xl_xid = InvalidTransactionId;
4133 heikki.linnakangas@i 5196 : 51 : record->xl_tot_len = SizeOfXLogRecord + SizeOfXLogRecordDataHeaderShort + sizeof(checkPoint);
9133 tgl@sss.pgh.pa.us 5197 : 51 : record->xl_info = XLOG_CHECKPOINT_SHUTDOWN;
9657 vadim4o@yahoo.com 5198 : 51 : record->xl_rmid = RM_XLOG_ID;
4133 heikki.linnakangas@i 5199 : 51 : recptr += SizeOfXLogRecord;
5200 : : /* fill the XLogRecordDataHeaderShort struct */
3274 tgl@sss.pgh.pa.us 5201 : 51 : *(recptr++) = (char) XLR_BLOCK_ID_DATA_SHORT;
4133 heikki.linnakangas@i 5202 : 51 : *(recptr++) = sizeof(checkPoint);
5203 : 51 : memcpy(recptr, &checkPoint, sizeof(checkPoint));
5204 : 51 : recptr += sizeof(checkPoint);
5205 [ - + ]: 51 : Assert(recptr - (char *) record == record->xl_tot_len);
5206 : :
4149 5207 : 51 : INIT_CRC32C(crc);
4133 5208 : 51 : COMP_CRC32C(crc, ((char *) record) + SizeOfXLogRecord, record->xl_tot_len - SizeOfXLogRecord);
4149 5209 : 51 : COMP_CRC32C(crc, (char *) record, offsetof(XLogRecord, xl_crc));
5210 : 51 : FIN_CRC32C(crc);
9208 vadim4o@yahoo.com 5211 : 51 : record->xl_crc = crc;
5212 : :
5213 : : /* Create first XLOG segment file */
1591 rhaas@postgresql.org 5214 : 51 : openLogTLI = BootstrapTimeLineID;
5215 : 51 : openLogFile = XLogFileInit(1, BootstrapTimeLineID);
5216 : :
5217 : : /*
5218 : : * We needn't bother with Reserve/ReleaseExternalFD here, since we'll
5219 : : * close the file again in a moment.
5220 : : */
5221 : :
5222 : : /* Write the first page with the initial record */
9048 tgl@sss.pgh.pa.us 5223 : 51 : errno = 0;
3284 rhaas@postgresql.org 5224 : 51 : pgstat_report_wait_start(WAIT_EVENT_WAL_BOOTSTRAP_WRITE);
97 peter@eisentraut.org 5225 [ - + ]:GNC 51 : if (write(openLogFile, &buffer, XLOG_BLCKSZ) != XLOG_BLCKSZ)
5226 : : {
5227 : : /* if write didn't set errno, assume problem is no disk space */
9048 tgl@sss.pgh.pa.us 5228 [ # # ]:UBC 0 : if (errno == 0)
5229 : 0 : errno = ENOSPC;
8273 5230 [ # # ]: 0 : ereport(PANIC,
5231 : : (errcode_for_file_access(),
5232 : : errmsg("could not write bootstrap write-ahead log file: %m")));
5233 : : }
3284 rhaas@postgresql.org 5234 :CBC 51 : pgstat_report_wait_end();
5235 : :
5236 : 51 : pgstat_report_wait_start(WAIT_EVENT_WAL_BOOTSTRAP_SYNC);
9133 tgl@sss.pgh.pa.us 5237 [ - + ]: 51 : if (pg_fsync(openLogFile) != 0)
8273 tgl@sss.pgh.pa.us 5238 [ # # ]:UBC 0 : ereport(PANIC,
5239 : : (errcode_for_file_access(),
5240 : : errmsg("could not fsync bootstrap write-ahead log file: %m")));
3284 rhaas@postgresql.org 5241 :CBC 51 : pgstat_report_wait_end();
5242 : :
2444 peter@eisentraut.org 5243 [ - + ]: 51 : if (close(openLogFile) != 0)
8084 tgl@sss.pgh.pa.us 5244 [ # # ]:UBC 0 : ereport(PANIC,
5245 : : (errcode_for_file_access(),
5246 : : errmsg("could not close bootstrap write-ahead log file: %m")));
5247 : :
9133 tgl@sss.pgh.pa.us 5248 :CBC 51 : openLogFile = -1;
5249 : :
5250 : : /* Now create pg_control */
600 peter@eisentraut.org 5251 : 51 : InitControlFile(sysidentifier, data_checksum_version);
9133 tgl@sss.pgh.pa.us 5252 : 51 : ControlFile->time = checkPoint.time;
9657 vadim4o@yahoo.com 5253 : 51 : ControlFile->checkPoint = checkPoint.redo;
9133 tgl@sss.pgh.pa.us 5254 : 51 : ControlFile->checkPointCopy = checkPoint;
5255 : :
5256 : : /* some additional ControlFile fields are set in WriteControlFile() */
9241 5257 : 51 : WriteControlFile();
5258 : :
5259 : : /* Bootstrap the commit log, too */
8968 5260 : 51 : BootStrapCLOG();
4120 alvherre@alvh.no-ip. 5261 : 51 : BootStrapCommitTs();
7927 tgl@sss.pgh.pa.us 5262 : 51 : BootStrapSUBTRANS();
7626 5263 : 51 : BootStrapMultiXact();
5264 : :
5265 : : /*
5266 : : * Force control file to be read - in contrast to normal processing we'd
5267 : : * otherwise never run the checks and GUC related initializations therein.
5268 : : */
3105 andres@anarazel.de 5269 : 51 : ReadControlFile();
9657 vadim4o@yahoo.com 5270 : 51 : }
5271 : :
5272 : : static char *
225 tgl@sss.pgh.pa.us 5273 :GNC 892 : str_time(pg_time_t tnow, char *buf, size_t bufsize)
5274 : : {
5275 : 892 : pg_strftime(buf, bufsize,
5276 : : "%Y-%m-%d %H:%M:%S %Z",
6798 tgl@sss.pgh.pa.us 5277 :CBC 892 : pg_localtime(&tnow, log_timezone));
5278 : :
9245 peter_e@gmx.net 5279 : 892 : return buf;
5280 : : }
5281 : :
5282 : : /*
5283 : : * Initialize the first WAL segment on new timeline.
5284 : : */
5285 : : static void
1488 heikki.linnakangas@i 5286 : 55 : XLogInitNewTimeline(TimeLineID endTLI, XLogRecPtr endOfLog, TimeLineID newTLI)
5287 : : {
5288 : : char xlogfname[MAXFNAMELEN];
5289 : : XLogSegNo endLogSegNo;
5290 : : XLogSegNo startLogSegNo;
5291 : :
5292 : : /* we always switch to a new timeline after archive recovery */
1591 rhaas@postgresql.org 5293 [ - + ]: 55 : Assert(endTLI != newTLI);
5294 : :
5295 : : /*
5296 : : * Update min recovery point one last time.
5297 : : */
6107 heikki.linnakangas@i 5298 : 55 : UpdateMinRecoveryPoint(InvalidXLogRecPtr, true);
5299 : :
5300 : : /*
5301 : : * Calculate the last segment on the old timeline, and the first segment
5302 : : * on the new timeline. If the switch happens in the middle of a segment,
5303 : : * they are the same, but if the switch happens exactly at a segment
5304 : : * boundary, startLogSegNo will be endLogSegNo + 1.
5305 : : */
3099 andres@anarazel.de 5306 : 55 : XLByteToPrevSeg(endOfLog, endLogSegNo, wal_segment_size);
5307 : 55 : XLByteToSeg(endOfLog, startLogSegNo, wal_segment_size);
5308 : :
5309 : : /*
5310 : : * Initialize the starting WAL segment for the new timeline. If the switch
5311 : : * happens in the middle of a segment, copy data from the last WAL segment
5312 : : * of the old timeline up to the switch point, to the starting WAL segment
5313 : : * on the new timeline.
5314 : : */
4105 heikki.linnakangas@i 5315 [ + + ]: 55 : if (endLogSegNo == startLogSegNo)
5316 : : {
5317 : : /*
5318 : : * Make a copy of the file on the new timeline.
5319 : : *
5320 : : * Writing WAL isn't allowed yet, so there are no locking
5321 : : * considerations. But we should be just as tense as XLogFileInit to
5322 : : * avoid emplacing a bogus file.
5323 : : */
1591 rhaas@postgresql.org 5324 : 43 : XLogFileCopy(newTLI, endLogSegNo, endTLI, endLogSegNo,
3099 andres@anarazel.de 5325 : 43 : XLogSegmentOffset(endOfLog, wal_segment_size));
5326 : : }
5327 : : else
5328 : : {
5329 : : /*
5330 : : * The switch happened at a segment boundary, so just create the next
5331 : : * segment on the new timeline.
5332 : : */
5333 : : int fd;
5334 : :
1591 rhaas@postgresql.org 5335 : 12 : fd = XLogFileInit(startLogSegNo, newTLI);
5336 : :
2444 peter@eisentraut.org 5337 [ - + ]: 12 : if (close(fd) != 0)
5338 : : {
2294 michael@paquier.xyz 5339 :UBC 0 : int save_errno = errno;
5340 : :
1591 rhaas@postgresql.org 5341 : 0 : XLogFileName(xlogfname, newTLI, startLogSegNo, wal_segment_size);
2294 michael@paquier.xyz 5342 : 0 : errno = save_errno;
4102 heikki.linnakangas@i 5343 [ # # ]: 0 : ereport(ERROR,
5344 : : (errcode_for_file_access(),
5345 : : errmsg("could not close file \"%s\": %m", xlogfname)));
5346 : : }
5347 : : }
5348 : :
5349 : : /*
5350 : : * Let's just make real sure there are not .ready or .done flags posted
5351 : : * for the new segment.
5352 : : */
1591 rhaas@postgresql.org 5353 :CBC 55 : XLogFileName(xlogfname, newTLI, startLogSegNo, wal_segment_size);
4161 fujii@postgresql.org 5354 : 55 : XLogArchiveCleanup(xlogfname);
7909 tgl@sss.pgh.pa.us 5355 : 55 : }
5356 : :
5357 : : /*
5358 : : * Perform cleanup actions at the conclusion of archive recovery.
5359 : : */
5360 : : static void
1591 rhaas@postgresql.org 5361 : 55 : CleanupAfterArchiveRecovery(TimeLineID EndOfLogTLI, XLogRecPtr EndOfLog,
5362 : : TimeLineID newTLI)
5363 : : {
5364 : : /*
5365 : : * Execute the recovery_end_command, if any.
5366 : : */
1614 5367 [ + - + + ]: 55 : if (recoveryEndCommand && strcmp(recoveryEndCommand, "") != 0)
1133 michael@paquier.xyz 5368 : 2 : ExecuteRecoveryCommand(recoveryEndCommand,
5369 : : "recovery_end_command",
5370 : : true,
5371 : : WAIT_EVENT_RECOVERY_END_COMMAND);
5372 : :
5373 : : /*
5374 : : * We switched to a new timeline. Clean up segments on the old timeline.
5375 : : *
5376 : : * If there are any higher-numbered segments on the old timeline, remove
5377 : : * them. They might contain valid WAL, but they might also be
5378 : : * pre-allocated files containing garbage. In any case, they are not part
5379 : : * of the new timeline's history so we don't need them.
5380 : : */
1591 rhaas@postgresql.org 5381 : 55 : RemoveNonParentXlogFiles(EndOfLog, newTLI);
5382 : :
5383 : : /*
5384 : : * If the switch happened in the middle of a segment, what to do with the
5385 : : * last, partial segment on the old timeline? If we don't archive it, and
5386 : : * the server that created the WAL never archives it either (e.g. because
5387 : : * it was hit by a meteor), it will never make it to the archive. That's
5388 : : * OK from our point of view, because the new segment that we created with
5389 : : * the new TLI contains all the WAL from the old timeline up to the switch
5390 : : * point. But if you later try to do PITR to the "missing" WAL on the old
5391 : : * timeline, recovery won't find it in the archive. It's physically
5392 : : * present in the new file with new TLI, but recovery won't look there
5393 : : * when it's recovering to the older timeline. On the other hand, if we
5394 : : * archive the partial segment, and the original server on that timeline
5395 : : * is still running and archives the completed version of the same segment
5396 : : * later, it will fail. (We used to do that in 9.4 and below, and it
5397 : : * caused such problems).
5398 : : *
5399 : : * As a compromise, we rename the last segment with the .partial suffix,
5400 : : * and archive it. Archive recovery will never try to read .partial
5401 : : * segments, so they will normally go unused. But in the odd PITR case,
5402 : : * the administrator can copy them manually to the pg_wal directory
5403 : : * (removing the suffix). They can be useful in debugging, too.
5404 : : *
5405 : : * If a .done or .ready file already exists for the old timeline, however,
5406 : : * we had already determined that the segment is complete, so we can let
5407 : : * it be archived normally. (In particular, if it was restored from the
5408 : : * archive to begin with, it's expected to have a .done file).
5409 : : */
1614 5410 [ + + + + ]: 98 : if (XLogSegmentOffset(EndOfLog, wal_segment_size) != 0 &&
5411 [ + + - + ]: 43 : XLogArchivingActive())
5412 : : {
5413 : : char origfname[MAXFNAMELEN];
5414 : : XLogSegNo endLogSegNo;
5415 : :
5416 : 9 : XLByteToPrevSeg(EndOfLog, endLogSegNo, wal_segment_size);
5417 : 9 : XLogFileName(origfname, EndOfLogTLI, endLogSegNo, wal_segment_size);
5418 : :
5419 [ + + ]: 9 : if (!XLogArchiveIsReadyOrDone(origfname))
5420 : : {
5421 : : char origpath[MAXPGPATH];
5422 : : char partialfname[MAXFNAMELEN];
5423 : : char partialpath[MAXPGPATH];
5424 : :
5425 : : /*
5426 : : * If we're summarizing WAL, we can't rename the partial file
5427 : : * until the summarizer finishes with it, else it will fail.
5428 : : */
597 5429 [ + + ]: 5 : if (summarize_wal)
5430 : 1 : WaitForWalSummarization(EndOfLog);
5431 : :
1614 5432 : 5 : XLogFilePath(origpath, EndOfLogTLI, endLogSegNo, wal_segment_size);
5433 : 5 : snprintf(partialfname, MAXFNAMELEN, "%s.partial", origfname);
5434 : 5 : snprintf(partialpath, MAXPGPATH, "%s.partial", origpath);
5435 : :
5436 : : /*
5437 : : * Make sure there's no .done or .ready file for the .partial
5438 : : * file.
5439 : : */
5440 : 5 : XLogArchiveCleanup(partialfname);
5441 : :
5442 : 5 : durable_rename(origpath, partialpath, ERROR);
5443 : 5 : XLogArchiveNotify(partialfname);
5444 : : }
5445 : : }
5446 : 55 : }
5447 : :
5448 : : /*
5449 : : * Check to see if required parameters are set high enough on this server
5450 : : * for various aspects of recovery operation.
5451 : : *
5452 : : * Note that all the parameters which this function tests need to be
5453 : : * listed in Administrator's Overview section in high-availability.sgml.
5454 : : * If you change them, don't forget to update the list.
5455 : : */
5456 : : static void
1488 heikki.linnakangas@i 5457 : 262 : CheckRequiredParameterValues(void)
5458 : : {
5459 : : /*
5460 : : * For archive recovery, the WAL must be generated with at least 'replica'
5461 : : * wal_level.
5462 : : */
5463 [ + + + + ]: 262 : if (ArchiveRecoveryRequested && ControlFile->wal_level == WAL_LEVEL_MINIMAL)
5464 : : {
5465 [ + - ]: 2 : ereport(FATAL,
5466 : : (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
5467 : : errmsg("WAL was generated with \"wal_level=minimal\", cannot continue recovering"),
5468 : : errdetail("This happens if you temporarily set \"wal_level=minimal\" on the server."),
5469 : : errhint("Use a backup taken after setting \"wal_level\" to higher than \"minimal\".")));
5470 : : }
5471 : :
5472 : : /*
5473 : : * For Hot Standby, the WAL must be generated with 'replica' mode, and we
5474 : : * must have at least as many backend slots as the primary.
5475 : : */
4393 5476 [ + + + + ]: 260 : if (ArchiveRecoveryRequested && EnableHotStandby)
5477 : : {
5478 : : /* We ignore autovacuum_worker_slots when we make this test. */
5800 5479 : 136 : RecoveryRequiresIntParameter("max_connections",
5480 : : MaxConnections,
5799 tgl@sss.pgh.pa.us 5481 : 136 : ControlFile->MaxConnections);
4637 rhaas@postgresql.org 5482 : 136 : RecoveryRequiresIntParameter("max_worker_processes",
5483 : : max_worker_processes,
5484 : 136 : ControlFile->max_worker_processes);
2588 michael@paquier.xyz 5485 : 136 : RecoveryRequiresIntParameter("max_wal_senders",
5486 : : max_wal_senders,
5487 : 136 : ControlFile->max_wal_senders);
4939 tgl@sss.pgh.pa.us 5488 : 136 : RecoveryRequiresIntParameter("max_prepared_transactions",
5489 : : max_prepared_xacts,
5799 5490 : 136 : ControlFile->max_prepared_xacts);
4939 5491 : 136 : RecoveryRequiresIntParameter("max_locks_per_transaction",
5492 : : max_locks_per_xact,
5799 5493 : 136 : ControlFile->max_locks_per_xact);
5494 : : }
5930 simon@2ndQuadrant.co 5495 : 260 : }
5496 : :
5497 : : /*
5498 : : * This must be called ONCE during postmaster or standalone-backend startup
5499 : : */
5500 : : void
9133 tgl@sss.pgh.pa.us 5501 : 1004 : StartupXLOG(void)
5502 : : {
5503 : : XLogCtlInsert *Insert;
5504 : : CheckPoint checkPoint;
5505 : : bool wasShutdown;
5506 : : bool didCrash;
5507 : : bool haveTblspcMap;
5508 : : bool haveBackupLabel;
5509 : : XLogRecPtr EndOfLog;
5510 : : TimeLineID EndOfLogTLI;
5511 : : TimeLineID newTLI;
5512 : : bool performedWalRecovery;
5513 : : EndOfWalRecoveryInfo *endOfRecoveryInfo;
5514 : : XLogRecPtr abortedRecPtr;
5515 : : XLogRecPtr missingContrecPtr;
5516 : : TransactionId oldestActiveXID;
2055 fujii@postgresql.org 5517 : 1004 : bool promoted = false;
5518 : : char timebuf[128];
5519 : :
5520 : : /*
5521 : : * We should have an aux process resource owner to use, and we should not
5522 : : * be in a transaction that's installed some other resowner.
5523 : : */
2797 tgl@sss.pgh.pa.us 5524 [ - + ]: 1004 : Assert(AuxProcessResourceOwner != NULL);
5525 [ + - - + ]: 1004 : Assert(CurrentResourceOwner == NULL ||
5526 : : CurrentResourceOwner == AuxProcessResourceOwner);
5527 : 1004 : CurrentResourceOwner = AuxProcessResourceOwner;
5528 : :
5529 : : /*
5530 : : * Check that contents look valid.
5531 : : */
2319 peter@eisentraut.org 5532 [ - + ]: 1004 : if (!XRecOffIsValid(ControlFile->checkPoint))
8273 tgl@sss.pgh.pa.us 5533 [ # # ]:UBC 0 : ereport(FATAL,
5534 : : (errcode(ERRCODE_DATA_CORRUPTED),
5535 : : errmsg("control file contains invalid checkpoint location")));
5536 : :
2319 peter@eisentraut.org 5537 [ + + - - :CBC 1004 : switch (ControlFile->state)
+ + - ]
5538 : : {
5539 : 785 : case DB_SHUTDOWNED:
5540 : :
5541 : : /*
5542 : : * This is the expected case, so don't be chatty in standalone
5543 : : * mode
5544 : : */
5545 [ + + + + ]: 785 : ereport(IsPostmasterEnvironment ? LOG : NOTICE,
5546 : : (errmsg("database system was shut down at %s",
5547 : : str_time(ControlFile->time,
5548 : : timebuf, sizeof(timebuf)))));
5549 : 785 : break;
5550 : :
5551 : 33 : case DB_SHUTDOWNED_IN_RECOVERY:
5552 [ + - ]: 33 : ereport(LOG,
5553 : : (errmsg("database system was shut down in recovery at %s",
5554 : : str_time(ControlFile->time,
5555 : : timebuf, sizeof(timebuf)))));
5556 : 33 : break;
5557 : :
2319 peter@eisentraut.org 5558 :UBC 0 : case DB_SHUTDOWNING:
5559 [ # # ]: 0 : ereport(LOG,
5560 : : (errmsg("database system shutdown was interrupted; last known up at %s",
5561 : : str_time(ControlFile->time,
5562 : : timebuf, sizeof(timebuf)))));
5563 : 0 : break;
5564 : :
5565 : 0 : case DB_IN_CRASH_RECOVERY:
5566 [ # # ]: 0 : ereport(LOG,
5567 : : (errmsg("database system was interrupted while in recovery at %s",
5568 : : str_time(ControlFile->time,
5569 : : timebuf, sizeof(timebuf))),
5570 : : errhint("This probably means that some data is corrupted and"
5571 : : " you will have to use the last backup for recovery.")));
5572 : 0 : break;
5573 : :
2319 peter@eisentraut.org 5574 :CBC 7 : case DB_IN_ARCHIVE_RECOVERY:
5575 [ + - ]: 7 : ereport(LOG,
5576 : : (errmsg("database system was interrupted while in recovery at log time %s",
5577 : : str_time(ControlFile->checkPointCopy.time,
5578 : : timebuf, sizeof(timebuf))),
5579 : : errhint("If this has occurred more than once some data might be corrupted"
5580 : : " and you might need to choose an earlier recovery target.")));
5581 : 7 : break;
5582 : :
5583 : 179 : case DB_IN_PRODUCTION:
5584 [ + - ]: 179 : ereport(LOG,
5585 : : (errmsg("database system was interrupted; last known up at %s",
5586 : : str_time(ControlFile->time,
5587 : : timebuf, sizeof(timebuf)))));
5588 : 179 : break;
5589 : :
2319 peter@eisentraut.org 5590 :UBC 0 : default:
5591 [ # # ]: 0 : ereport(FATAL,
5592 : : (errcode(ERRCODE_DATA_CORRUPTED),
5593 : : errmsg("control file contains invalid database cluster state")));
5594 : : }
5595 : :
5596 : : /* This is just to allow attaching to startup process with a debugger */
5597 : : #ifdef XLOG_REPLAY_DELAY
5598 : : if (ControlFile->state != DB_SHUTDOWNED)
5599 : : pg_usleep(60000000L);
5600 : : #endif
5601 : :
5602 : : /*
5603 : : * Verify that pg_wal, pg_wal/archive_status, and pg_wal/summaries exist.
5604 : : * In cases where someone has performed a copy for PITR, these directories
5605 : : * may have been excluded and need to be re-created.
5606 : : */
6335 tgl@sss.pgh.pa.us 5607 :CBC 1004 : ValidateXLOGDirectoryStructure();
5608 : :
5609 : : /* Set up timeout handler needed to report startup progress. */
1602 rhaas@postgresql.org 5610 [ + + ]: 1004 : if (!IsBootstrapProcessingMode())
5611 : 953 : RegisterTimeout(STARTUP_PROGRESS_TIMEOUT,
5612 : : startup_progress_timeout_handler);
5613 : :
5614 : : /*----------
5615 : : * If we previously crashed, perform a couple of actions:
5616 : : *
5617 : : * - The pg_wal directory may still include some temporary WAL segments
5618 : : * used when creating a new segment, so perform some clean up to not
5619 : : * bloat this path. This is done first as there is no point to sync
5620 : : * this temporary data.
5621 : : *
5622 : : * - There might be data which we had written, intending to fsync it, but
5623 : : * which we had not actually fsync'd yet. Therefore, a power failure in
5624 : : * the near future might cause earlier unflushed writes to be lost, even
5625 : : * though more recent data written to disk from here on would be
5626 : : * persisted. To avoid that, fsync the entire data directory.
5627 : : */
1488 heikki.linnakangas@i 5628 [ + + ]: 1004 : if (ControlFile->state != DB_SHUTDOWNED &&
5629 [ + + ]: 219 : ControlFile->state != DB_SHUTDOWNED_IN_RECOVERY)
5630 : : {
5631 : 186 : RemoveTempXlogFiles();
5632 : 186 : SyncDataDirectory();
1439 andres@anarazel.de 5633 : 186 : didCrash = true;
5634 : : }
5635 : : else
5636 : 818 : didCrash = false;
5637 : :
5638 : : /*
5639 : : * Prepare for WAL recovery if needed.
5640 : : *
5641 : : * InitWalRecovery analyzes the control file and the backup label file, if
5642 : : * any. It updates the in-memory ControlFile buffer according to the
5643 : : * starting checkpoint, and sets InRecovery and ArchiveRecoveryRequested.
5644 : : * It also applies the tablespace map file, if any.
5645 : : */
1488 heikki.linnakangas@i 5646 : 1004 : InitWalRecovery(ControlFile, &wasShutdown,
5647 : : &haveBackupLabel, &haveTblspcMap);
5648 : 1002 : checkPoint = ControlFile->checkPointCopy;
5649 : :
5650 : : /* initialize shared memory variables from the checkpoint record */
828 5651 : 1002 : TransamVariables->nextXid = checkPoint.nextXid;
5652 : 1002 : TransamVariables->nextOid = checkPoint.nextOid;
5653 : 1002 : TransamVariables->oidCount = 0;
7585 tgl@sss.pgh.pa.us 5654 : 1002 : MultiXactSetNextMXact(checkPoint.nextMulti, checkPoint.nextMultiOffset);
3279 rhaas@postgresql.org 5655 : 1002 : AdvanceOldestClogXid(checkPoint.oldestXid);
5870 tgl@sss.pgh.pa.us 5656 : 1002 : SetTransactionIdLimit(checkPoint.oldestXid, checkPoint.oldestXidDB);
96 heikki.linnakangas@i 5657 :GNC 1002 : SetMultiXactIdLimit(checkPoint.oldestMulti, checkPoint.oldestMultiDB);
3730 mail@joeconway.com 5658 :CBC 1002 : SetCommitTsLimit(checkPoint.oldestCommitTsXid,
5659 : : checkPoint.newestCommitTsXid);
5660 : :
5661 : : /*
5662 : : * Clear out any old relcache cache files. This is *necessary* if we do
5663 : : * any WAL replay, since that would probably result in the cache files
5664 : : * being out of sync with database reality. In theory we could leave them
5665 : : * in place if the database had been cleanly shut down, but it seems
5666 : : * safest to just remove them always and let them be rebuilt during the
5667 : : * first backend startup. These files needs to be removed from all
5668 : : * directories including pg_tblspc, however the symlinks are created only
5669 : : * after reading tablespace_map file in case of archive recovery from
5670 : : * backup, so needs to clear old relcache files here after creating
5671 : : * symlinks.
5672 : : */
1488 heikki.linnakangas@i 5673 : 1002 : RelationCacheInitFileRemove();
5674 : :
5675 : : /*
5676 : : * Initialize replication slots, before there's a chance to remove
5677 : : * required resources.
5678 : : */
4294 andres@anarazel.de 5679 : 1002 : StartupReplicationSlots();
5680 : :
5681 : : /*
5682 : : * Startup the logical decoding status with the last status stored in the
5683 : : * checkpoint record.
5684 : : */
82 msawada@postgresql.o 5685 :GNC 1000 : StartupLogicalDecodingStatus(checkPoint.logicalDecodingEnabled);
5686 : :
5687 : : /*
5688 : : * Startup logical state, needs to be setup now so we have proper data
5689 : : * during crash recovery.
5690 : : */
4395 rhaas@postgresql.org 5691 :CBC 1000 : StartupReorderBuffer();
5692 : :
5693 : : /*
5694 : : * Startup CLOG. This must be done after TransamVariables->nextXid has
5695 : : * been initialized and before we accept connections or begin WAL replay.
5696 : : */
1873 5697 : 1000 : StartupCLOG();
5698 : :
5699 : : /*
5700 : : * Startup MultiXact. We need to do this early to be able to replay
5701 : : * truncations.
5702 : : */
4489 alvherre@alvh.no-ip. 5703 : 1000 : StartupMultiXact();
5704 : :
5705 : : /*
5706 : : * Ditto for commit timestamps. Activate the facility if the setting is
5707 : : * enabled in the control file, as there should be no tracking of commit
5708 : : * timestamps done when the setting was disabled. This facility can be
5709 : : * started or stopped when replaying a XLOG_PARAMETER_CHANGE record.
5710 : : */
2727 michael@paquier.xyz 5711 [ + + ]: 1000 : if (ControlFile->track_commit_timestamp)
3747 alvherre@alvh.no-ip. 5712 : 14 : StartupCommitTs();
5713 : :
5714 : : /*
5715 : : * Recover knowledge about replay progress of known replication partners.
5716 : : */
3973 andres@anarazel.de 5717 : 1000 : StartupReplicationOrigin();
5718 : :
5719 : : /*
5720 : : * Initialize unlogged LSN. On a clean shutdown, it's restored from the
5721 : : * control file. On recovery, all unlogged relations are blown away, so
5722 : : * the unlogged LSN counter can be reset too.
5723 : : */
4780 heikki.linnakangas@i 5724 [ + + ]: 1000 : if (ControlFile->state == DB_SHUTDOWNED)
745 nathan@postgresql.or 5725 : 776 : pg_atomic_write_membarrier_u64(&XLogCtl->unloggedLSN,
5726 : 776 : ControlFile->unloggedLSN);
5727 : : else
5728 : 224 : pg_atomic_write_membarrier_u64(&XLogCtl->unloggedLSN,
5729 : : FirstNormalUnloggedLSN);
5730 : :
5731 : : /*
5732 : : * Copy any missing timeline history files between 'now' and the recovery
5733 : : * target timeline from archive to pg_wal. While we don't need those files
5734 : : * ourselves - the history file of the recovery target timeline covers all
5735 : : * the previous timelines in the history too - a cascading standby server
5736 : : * might be interested in them. Or, if you archive the WAL from this
5737 : : * server to a different archive than the primary, it'd be good for all
5738 : : * the history files to get archived there after failover, so that you can
5739 : : * use one of the old timelines as a PITR target. Timeline history files
5740 : : * are small, so it's better to copy them unnecessarily than not copy them
5741 : : * and regret later.
5742 : : */
1488 heikki.linnakangas@i 5743 : 1000 : restoreTimeLineHistoryFiles(checkPoint.ThisTimeLineID, recoveryTargetTLI);
5744 : :
5745 : : /*
5746 : : * Before running in recovery, scan pg_twophase and fill in its status to
5747 : : * be able to work on entries generated by redo. Doing a scan before
5748 : : * taking any recovery action has the merit to discard any 2PC files that
5749 : : * are newer than the first record to replay, saving from any conflicts at
5750 : : * replay. This avoids as well any subsequent scans when doing recovery
5751 : : * of the on-disk two-phase data.
5752 : : */
3267 simon@2ndQuadrant.co 5753 : 1000 : restoreTwoPhaseData();
5754 : :
5755 : : /*
5756 : : * When starting with crash recovery, reset pgstat data - it might not be
5757 : : * valid. Otherwise restore pgstat data. It's safe to do this here,
5758 : : * because postmaster will not yet have started any other processes.
5759 : : *
5760 : : * NB: Restoring replication slot stats relies on slot state to have
5761 : : * already been restored from disk.
5762 : : *
5763 : : * TODO: With a bit of extra work we could just start with a pgstat file
5764 : : * associated with the checkpoint redo location we're starting from.
5765 : : */
1439 andres@anarazel.de 5766 [ + + ]: 1000 : if (didCrash)
5767 : 184 : pgstat_discard_stats();
5768 : : else
363 michael@paquier.xyz 5769 : 816 : pgstat_restore_stats();
5770 : :
5163 simon@2ndQuadrant.co 5771 : 1000 : lastFullPageWrites = checkPoint.fullPageWrites;
5772 : :
4633 heikki.linnakangas@i 5773 : 1000 : RedoRecPtr = XLogCtl->RedoRecPtr = XLogCtl->Insert.RedoRecPtr = checkPoint.redo;
4147 5774 : 1000 : doPageWrites = lastFullPageWrites;
5775 : :
5776 : : /* REDO */
7893 tgl@sss.pgh.pa.us 5777 [ + + ]: 1000 : if (InRecovery)
5778 : : {
5779 : : /* Initialize state for RecoveryInProgress() */
1488 heikki.linnakangas@i 5780 [ - + ]: 224 : SpinLockAcquire(&XLogCtl->info_lck);
5781 [ + + ]: 224 : if (InArchiveRecovery)
5782 : 122 : XLogCtl->SharedRecoveryState = RECOVERY_STATE_ARCHIVE;
5783 : : else
5784 : 102 : XLogCtl->SharedRecoveryState = RECOVERY_STATE_CRASH;
5785 : 224 : SpinLockRelease(&XLogCtl->info_lck);
5786 : :
5787 : : /*
5788 : : * Update pg_control to show that we are recovering and to show the
5789 : : * selected checkpoint as the place we are starting from. We also mark
5790 : : * pg_control with any minimum recovery stop point obtained from a
5791 : : * backup history file.
5792 : : *
5793 : : * No need to hold ControlFileLock yet, we aren't up far enough.
5794 : : */
5795 : 224 : UpdateControlFile();
5796 : :
5797 : : /*
5798 : : * If there was a backup label file, it's done its job and the info
5799 : : * has now been propagated into pg_control. We must get rid of the
5800 : : * label file so that if we crash during recovery, we'll pick up at
5801 : : * the latest recovery restartpoint instead of going all the way back
5802 : : * to the backup start point. It seems prudent though to just rename
5803 : : * the file out of the way rather than delete it completely.
5804 : : */
5805 [ + + ]: 224 : if (haveBackupLabel)
5806 : : {
5807 : 80 : unlink(BACKUP_LABEL_OLD);
5808 : 80 : durable_rename(BACKUP_LABEL_FILE, BACKUP_LABEL_OLD, FATAL);
5809 : : }
5810 : :
5811 : : /*
5812 : : * If there was a tablespace_map file, it's done its job and the
5813 : : * symlinks have been created. We must get rid of the map file so
5814 : : * that if we crash during recovery, we don't create symlinks again.
5815 : : * It seems prudent though to just rename the file out of the way
5816 : : * rather than delete it completely.
5817 : : */
5818 [ + + ]: 224 : if (haveTblspcMap)
5819 : : {
5820 : 2 : unlink(TABLESPACE_MAP_OLD);
5821 : 2 : durable_rename(TABLESPACE_MAP, TABLESPACE_MAP_OLD, FATAL);
5822 : : }
5823 : :
5824 : : /*
5825 : : * Initialize our local copy of minRecoveryPoint. When doing crash
5826 : : * recovery we want to replay up to the end of WAL. Particularly, in
5827 : : * the case of a promoted standby minRecoveryPoint value in the
5828 : : * control file is only updated after the first checkpoint. However,
5829 : : * if the instance crashes before the first post-recovery checkpoint
5830 : : * is completed then recovery will use a stale location causing the
5831 : : * startup process to think that there are still invalid page
5832 : : * references when checking for data consistency.
5833 : : */
2810 michael@paquier.xyz 5834 [ + + ]: 224 : if (InArchiveRecovery)
5835 : : {
1488 heikki.linnakangas@i 5836 : 122 : LocalMinRecoveryPoint = ControlFile->minRecoveryPoint;
5837 : 122 : LocalMinRecoveryPointTLI = ControlFile->minRecoveryPointTLI;
5838 : : }
5839 : : else
5840 : : {
5841 : 102 : LocalMinRecoveryPoint = InvalidXLogRecPtr;
5842 : 102 : LocalMinRecoveryPointTLI = 0;
5843 : : }
5844 : :
5845 : : /* Check that the GUCs used to generate the WAL allow recovery */
5800 5846 : 224 : CheckRequiredParameterValues();
5847 : :
5848 : : /*
5849 : : * We're in recovery, so unlogged relations may be trashed and must be
5850 : : * reset. This should be done BEFORE allowing Hot Standby
5851 : : * connections, so that read-only backends don't try to read whatever
5852 : : * garbage is left over from before.
5853 : : */
5555 rhaas@postgresql.org 5854 : 224 : ResetUnloggedRelations(UNLOGGED_RELATION_CLEANUP);
5855 : :
5856 : : /*
5857 : : * Likewise, delete any saved transaction snapshot files that got left
5858 : : * behind by crashed backends.
5859 : : */
5258 tgl@sss.pgh.pa.us 5860 : 224 : DeleteAllExportedSnapshotFiles();
5861 : :
5862 : : /*
5863 : : * Initialize for Hot Standby, if enabled. We won't let backends in
5864 : : * yet, not until we've reached the min recovery point specified in
5865 : : * control file and we've established a recovery snapshot from a
5866 : : * running-xacts WAL record.
5867 : : */
4769 heikki.linnakangas@i 5868 [ + + + + ]: 224 : if (ArchiveRecoveryRequested && EnableHotStandby)
5869 : : {
5870 : : TransactionId *xids;
5871 : : int nxids;
5872 : :
5875 5873 [ + + ]: 114 : ereport(DEBUG1,
5874 : : (errmsg_internal("initializing for hot standby")));
5875 : :
5930 simon@2ndQuadrant.co 5876 : 114 : InitRecoveryTransactionEnvironment();
5877 : :
5878 [ + + ]: 114 : if (wasShutdown)
5879 : 26 : oldestActiveXID = PrescanPreparedTransactions(&xids, &nxids);
5880 : : else
5881 : 88 : oldestActiveXID = checkPoint.oldestActiveXid;
5882 [ - + ]: 114 : Assert(TransactionIdIsValid(oldestActiveXID));
5883 : :
5884 : : /* Tell procarray about the range of xids it has to deal with */
828 heikki.linnakangas@i 5885 : 114 : ProcArrayInitRecovery(XidFromFullTransactionId(TransamVariables->nextXid));
5886 : :
5887 : : /*
5888 : : * Startup subtrans only. CLOG, MultiXact and commit timestamp
5889 : : * have already been started up and other SLRUs are not maintained
5890 : : * during recovery and need not be started yet.
5891 : : */
5930 simon@2ndQuadrant.co 5892 : 114 : StartupSUBTRANS(oldestActiveXID);
5893 : :
5894 : : /*
5895 : : * If we're beginning at a shutdown checkpoint, we know that
5896 : : * nothing was running on the primary at this point. So fake-up an
5897 : : * empty running-xacts record and use that here and now. Recover
5898 : : * additional standby state for prepared transactions.
5899 : : */
5815 heikki.linnakangas@i 5900 [ + + ]: 114 : if (wasShutdown)
5901 : : {
5902 : : RunningTransactionsData running;
5903 : : TransactionId latestCompletedXid;
5904 : :
5905 : : /* Update pg_subtrans entries for any prepared transactions */
626 5906 : 26 : StandbyRecoverPreparedTransactions();
5907 : :
5908 : : /*
5909 : : * Construct a RunningTransactions snapshot representing a
5910 : : * shut down server, with only prepared transactions still
5911 : : * alive. We're never overflowed at this point because all
5912 : : * subxids are listed with their parent prepared transactions.
5913 : : */
5815 5914 : 26 : running.xcnt = nxids;
4851 simon@2ndQuadrant.co 5915 : 26 : running.subxcnt = 0;
626 heikki.linnakangas@i 5916 : 26 : running.subxid_status = SUBXIDS_IN_SUBTRANS;
2042 andres@anarazel.de 5917 : 26 : running.nextXid = XidFromFullTransactionId(checkPoint.nextXid);
5815 heikki.linnakangas@i 5918 : 26 : running.oldestRunningXid = oldestActiveXID;
2042 andres@anarazel.de 5919 : 26 : latestCompletedXid = XidFromFullTransactionId(checkPoint.nextXid);
5785 simon@2ndQuadrant.co 5920 [ - + ]: 26 : TransactionIdRetreat(latestCompletedXid);
5784 5921 [ - + ]: 26 : Assert(TransactionIdIsNormal(latestCompletedXid));
5785 5922 : 26 : running.latestCompletedXid = latestCompletedXid;
5815 heikki.linnakangas@i 5923 : 26 : running.xids = xids;
5924 : :
5925 : 26 : ProcArrayApplyRecoveryInfo(&running);
5926 : : }
5927 : : }
5928 : :
5929 : : /*
5930 : : * We're all set for replaying the WAL now. Do it.
5931 : : */
1488 5932 : 224 : PerformWalRecovery();
5933 : 163 : performedWalRecovery = true;
5934 : : }
5935 : : else
1484 5936 : 776 : performedWalRecovery = false;
5937 : :
5938 : : /*
5939 : : * Finish WAL recovery.
5940 : : */
1488 5941 : 939 : endOfRecoveryInfo = FinishWalRecovery();
5942 : 939 : EndOfLog = endOfRecoveryInfo->endOfLog;
5943 : 939 : EndOfLogTLI = endOfRecoveryInfo->endOfLogTLI;
5944 : 939 : abortedRecPtr = endOfRecoveryInfo->abortedRecPtr;
5945 : 939 : missingContrecPtr = endOfRecoveryInfo->missingContrecPtr;
5946 : :
5947 : : /*
5948 : : * Reset ps status display, so as no information related to recovery shows
5949 : : * up.
5950 : : */
1270 michael@paquier.xyz 5951 : 939 : set_ps_display("");
5952 : :
5953 : : /*
5954 : : * When recovering from a backup (we are in recovery, and archive recovery
5955 : : * was requested), complain if we did not roll forward far enough to reach
5956 : : * the point where the database is consistent. For regular online
5957 : : * backup-from-primary, that means reaching the end-of-backup WAL record
5958 : : * (at which point we reset backupStartPoint to be Invalid), for
5959 : : * backup-from-replica (which can't inject records into the WAL stream),
5960 : : * that point is when we reach the minRecoveryPoint in pg_control (which
5961 : : * we purposefully copy last when backing up from a replica). For
5962 : : * pg_rewind (which creates a backup_label with a method of "pg_rewind")
5963 : : * or snapshot-style backups (which don't), backupEndRequired will be set
5964 : : * to false.
5965 : : *
5966 : : * Note: it is indeed okay to look at the local variable
5967 : : * LocalMinRecoveryPoint here, even though ControlFile->minRecoveryPoint
5968 : : * might be further ahead --- ControlFile->minRecoveryPoint cannot have
5969 : : * been advanced beyond the WAL we processed.
5970 : : */
5464 heikki.linnakangas@i 5971 [ + + ]: 939 : if (InRecovery &&
1488 5972 [ + - ]: 163 : (EndOfLog < LocalMinRecoveryPoint ||
129 alvherre@kurilemu.de 5973 [ - + ]:GNC 163 : XLogRecPtrIsValid(ControlFile->backupStartPoint)))
5974 : : {
5975 : : /*
5976 : : * Ran off end of WAL before reaching end-of-backup WAL record, or
5977 : : * minRecoveryPoint. That's a bad sign, indicating that you tried to
5978 : : * recover from an online backup but never called pg_backup_stop(), or
5979 : : * you didn't archive all the WAL needed.
5980 : : */
4769 heikki.linnakangas@i 5981 [ # # # # ]:UBC 0 : if (ArchiveRecoveryRequested || ControlFile->backupEndRequired)
5982 : : {
129 alvherre@kurilemu.de 5983 [ # # # # ]:UNC 0 : if (XLogRecPtrIsValid(ControlFile->backupStartPoint) || ControlFile->backupEndRequired)
5331 heikki.linnakangas@i 5984 [ # # ]:UBC 0 : ereport(FATAL,
5985 : : (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
5986 : : errmsg("WAL ends before end of online backup"),
5987 : : errhint("All WAL generated while online backup was taken must be available at recovery.")));
5988 : : else
5450 5989 [ # # ]: 0 : ereport(FATAL,
5990 : : (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
5991 : : errmsg("WAL ends before consistent recovery point")));
5992 : : }
5993 : : }
5994 : :
5995 : : /*
5996 : : * Reset unlogged relations to the contents of their INIT fork. This is
5997 : : * done AFTER recovery is complete so as to include any unlogged relations
5998 : : * created during recovery, but BEFORE recovery is marked as having
5999 : : * completed successfully. Otherwise we'd not retry if any of the post
6000 : : * end-of-recovery steps fail.
6001 : : */
1488 heikki.linnakangas@i 6002 [ + + ]:CBC 939 : if (InRecovery)
6003 : 163 : ResetUnloggedRelations(UNLOGGED_RELATION_INIT);
6004 : :
6005 : : /*
6006 : : * Pre-scan prepared transactions to find out the range of XIDs present.
6007 : : * This information is not quite needed yet, but it is positioned here so
6008 : : * as potential problems are detected before any on-disk change is done.
6009 : : */
2806 michael@paquier.xyz 6010 : 939 : oldestActiveXID = PrescanPreparedTransactions(NULL, NULL);
6011 : :
6012 : : /*
6013 : : * Allow ordinary WAL segment creation before possibly switching to a new
6014 : : * timeline, which creates a new segment, and after the last ReadRecord().
6015 : : */
1306 6016 : 939 : SetInstallXLogFileSegmentActive();
6017 : :
6018 : : /*
6019 : : * Consider whether we need to assign a new timeline ID.
6020 : : *
6021 : : * If we did archive recovery, we always assign a new ID. This handles a
6022 : : * couple of issues. If we stopped short of the end of WAL during
6023 : : * recovery, then we are clearly generating a new timeline and must assign
6024 : : * it a unique new ID. Even if we ran to the end, modifying the current
6025 : : * last segment is problematic because it may result in trying to
6026 : : * overwrite an already-archived copy of that segment, and we encourage
6027 : : * DBAs to make their archive_commands reject that. We can dodge the
6028 : : * problem by making the new active segment have a new timeline ID.
6029 : : *
6030 : : * In a normal crash recovery, we can just extend the timeline we were in.
6031 : : */
1488 heikki.linnakangas@i 6032 : 939 : newTLI = endOfRecoveryInfo->lastRecTLI;
4769 6033 [ + + ]: 939 : if (ArchiveRecoveryRequested)
6034 : : {
1586 rhaas@postgresql.org 6035 : 55 : newTLI = findNewestTimeLine(recoveryTargetTLI) + 1;
7907 tgl@sss.pgh.pa.us 6036 [ + - ]: 55 : ereport(LOG,
6037 : : (errmsg("selected new timeline ID: %u", newTLI)));
6038 : :
6039 : : /*
6040 : : * Make a writable copy of the last WAL segment. (Note that we also
6041 : : * have a copy of the last block of the old WAL in
6042 : : * endOfRecovery->lastPage; we will use that below.)
6043 : : */
1488 heikki.linnakangas@i 6044 : 55 : XLogInitNewTimeline(EndOfLogTLI, EndOfLog, newTLI);
6045 : :
6046 : : /*
6047 : : * Remove the signal files out of the way, so that we don't
6048 : : * accidentally re-enter archive recovery mode in a subsequent crash.
6049 : : */
6050 [ + + ]: 55 : if (endOfRecoveryInfo->standby_signal_file_found)
6051 : 52 : durable_unlink(STANDBY_SIGNAL_FILE, FATAL);
6052 : :
6053 [ + + ]: 55 : if (endOfRecoveryInfo->recovery_signal_file_found)
6054 : 4 : durable_unlink(RECOVERY_SIGNAL_FILE, FATAL);
6055 : :
6056 : : /*
6057 : : * Write the timeline history file, and have it archived. After this
6058 : : * point (or rather, as soon as the file is archived), the timeline
6059 : : * will appear as "taken" in the WAL archive and to any standby
6060 : : * servers. If we crash before actually switching to the new
6061 : : * timeline, standby servers will nevertheless think that we switched
6062 : : * to the new timeline, and will try to connect to the new timeline.
6063 : : * To minimize the window for that, try to do as little as possible
6064 : : * between here and writing the end-of-recovery record.
6065 : : */
1586 rhaas@postgresql.org 6066 : 55 : writeTimeLineHistory(newTLI, recoveryTargetTLI,
6067 : : EndOfLog, endOfRecoveryInfo->recoveryStopReason);
6068 : :
1488 heikki.linnakangas@i 6069 [ + - ]: 55 : ereport(LOG,
6070 : : (errmsg("archive recovery complete")));
6071 : : }
6072 : :
6073 : : /* Save the selected TimeLineID in shared memory, too */
597 rhaas@postgresql.org 6074 [ - + ]: 939 : SpinLockAcquire(&XLogCtl->info_lck);
1586 6075 : 939 : XLogCtl->InsertTimeLineID = newTLI;
1488 heikki.linnakangas@i 6076 : 939 : XLogCtl->PrevTimeLineID = endOfRecoveryInfo->lastRecTLI;
597 rhaas@postgresql.org 6077 : 939 : SpinLockRelease(&XLogCtl->info_lck);
6078 : :
6079 : : /*
6080 : : * Actually, if WAL ended in an incomplete record, skip the parts that
6081 : : * made it through and start writing after the portion that persisted.
6082 : : * (It's critical to first write an OVERWRITE_CONTRECORD message, which
6083 : : * we'll do as soon as we're open for writing new WAL.)
6084 : : */
129 alvherre@kurilemu.de 6085 [ + + ]:GNC 939 : if (XLogRecPtrIsValid(missingContrecPtr))
6086 : : {
6087 : : /*
6088 : : * We should only have a missingContrecPtr if we're not switching to a
6089 : : * new timeline. When a timeline switch occurs, WAL is copied from the
6090 : : * old timeline to the new only up to the end of the last complete
6091 : : * record, so there can't be an incomplete WAL record that we need to
6092 : : * disregard.
6093 : : */
1294 rhaas@postgresql.org 6094 [ - + ]:CBC 12 : Assert(newTLI == endOfRecoveryInfo->lastRecTLI);
129 alvherre@kurilemu.de 6095 [ - + ]:GNC 12 : Assert(XLogRecPtrIsValid(abortedRecPtr));
1628 alvherre@alvh.no-ip. 6096 :CBC 12 : EndOfLog = missingContrecPtr;
6097 : : }
6098 : :
6099 : : /*
6100 : : * Prepare to write WAL starting at EndOfLog location, and init xlog
6101 : : * buffer cache using the block containing the last record from the
6102 : : * previous incarnation.
6103 : : */
9269 vadim4o@yahoo.com 6104 : 939 : Insert = &XLogCtl->Insert;
1488 heikki.linnakangas@i 6105 : 939 : Insert->PrevBytePos = XLogRecPtrToBytePos(endOfRecoveryInfo->lastRec);
4624 6106 : 939 : Insert->CurrBytePos = XLogRecPtrToBytePos(EndOfLog);
6107 : :
6108 : : /*
6109 : : * Tricky point here: lastPage contains the *last* block that the LastRec
6110 : : * record spans, not the one it starts in. The last block is indeed the
6111 : : * one we want to use.
6112 : : */
6113 [ + + ]: 939 : if (EndOfLog % XLOG_BLCKSZ != 0)
6114 : : {
6115 : : char *page;
6116 : : int len;
6117 : : int firstIdx;
6118 : :
6119 : 905 : firstIdx = XLogRecPtrToBufIdx(EndOfLog);
1488 6120 : 905 : len = EndOfLog - endOfRecoveryInfo->lastPageBeginPtr;
6121 [ - + ]: 905 : Assert(len < XLOG_BLCKSZ);
6122 : :
6123 : : /* Copy the valid part of the last block, and zero the rest */
4624 6124 : 905 : page = &XLogCtl->pages[firstIdx * XLOG_BLCKSZ];
1488 6125 : 905 : memcpy(page, endOfRecoveryInfo->lastPage, len);
4624 6126 : 905 : memset(page + len, 0, XLOG_BLCKSZ - len);
6127 : :
817 jdavis@postgresql.or 6128 : 905 : pg_atomic_write_u64(&XLogCtl->xlblocks[firstIdx], endOfRecoveryInfo->lastPageBeginPtr + XLOG_BLCKSZ);
205 akorotkov@postgresql 6129 : 905 : XLogCtl->InitializedUpTo = endOfRecoveryInfo->lastPageBeginPtr + XLOG_BLCKSZ;
6130 : : }
6131 : : else
6132 : : {
6133 : : /*
6134 : : * There is no partial block to copy. Just set InitializedUpTo, and
6135 : : * let the first attempt to insert a log record to initialize the next
6136 : : * buffer.
6137 : : */
6138 : 34 : XLogCtl->InitializedUpTo = EndOfLog;
6139 : : }
6140 : :
6141 : : /*
6142 : : * Update local and shared status. This is OK to do without any locks
6143 : : * because no other process can be reading or writing WAL yet.
6144 : : */
4624 heikki.linnakangas@i 6145 : 939 : LogwrtResult.Write = LogwrtResult.Flush = EndOfLog;
707 alvherre@alvh.no-ip. 6146 : 939 : pg_atomic_write_u64(&XLogCtl->logInsertResult, EndOfLog);
709 6147 : 939 : pg_atomic_write_u64(&XLogCtl->logWriteResult, EndOfLog);
6148 : 939 : pg_atomic_write_u64(&XLogCtl->logFlushResult, EndOfLog);
4624 heikki.linnakangas@i 6149 : 939 : XLogCtl->LogwrtRqst.Write = EndOfLog;
6150 : 939 : XLogCtl->LogwrtRqst.Flush = EndOfLog;
6151 : :
6152 : : /*
6153 : : * Preallocate additional log files, if wanted.
6154 : : */
1586 rhaas@postgresql.org 6155 : 939 : PreallocXlogFiles(EndOfLog, newTLI);
6156 : :
6157 : : /*
6158 : : * Okay, we're officially UP.
6159 : : */
9269 vadim4o@yahoo.com 6160 : 939 : InRecovery = false;
6161 : :
6162 : : /* start the archive_timeout timer and LSN running */
4624 heikki.linnakangas@i 6163 : 939 : XLogCtl->lastSegSwitchTime = (pg_time_t) time(NULL);
3370 andres@anarazel.de 6164 : 939 : XLogCtl->lastSegSwitchLSN = EndOfLog;
6165 : :
6166 : : /* also initialize latestCompletedXid, to nextXid - 1 */
5151 tgl@sss.pgh.pa.us 6167 : 939 : LWLockAcquire(ProcArrayLock, LW_EXCLUSIVE);
828 heikki.linnakangas@i 6168 : 939 : TransamVariables->latestCompletedXid = TransamVariables->nextXid;
6169 : 939 : FullTransactionIdRetreat(&TransamVariables->latestCompletedXid);
5151 tgl@sss.pgh.pa.us 6170 : 939 : LWLockRelease(ProcArrayLock);
6171 : :
6172 : : /*
6173 : : * Start up subtrans, if not already done for hot standby. (commit
6174 : : * timestamps are started below, if necessary.)
6175 : : */
5930 simon@2ndQuadrant.co 6176 [ + + ]: 939 : if (standbyState == STANDBY_DISABLED)
6177 : 884 : StartupSUBTRANS(oldestActiveXID);
6178 : :
6179 : : /*
6180 : : * Perform end of recovery actions for any SLRUs that need it.
6181 : : */
5247 6182 : 939 : TrimCLOG();
4489 alvherre@alvh.no-ip. 6183 : 939 : TrimMultiXact();
6184 : :
6185 : : /*
6186 : : * Reload shared-memory state for prepared transactions. This needs to
6187 : : * happen before renaming the last partial segment of the old timeline as
6188 : : * it may be possible that we have to recover some transactions from it.
6189 : : */
7576 tgl@sss.pgh.pa.us 6190 : 939 : RecoverPreparedTransactions();
6191 : :
6192 : : /* Shut down xlogreader */
1488 heikki.linnakangas@i 6193 : 939 : ShutdownWalRecovery();
6194 : :
6195 : : /* Enable WAL writes for this backend only. */
1613 rhaas@postgresql.org 6196 : 939 : LocalSetXLogInsertAllowed();
6197 : :
6198 : : /* If necessary, write overwrite-contrecord before doing anything else */
129 alvherre@kurilemu.de 6199 [ + + ]:GNC 939 : if (XLogRecPtrIsValid(abortedRecPtr))
6200 : : {
6201 [ - + ]: 12 : Assert(XLogRecPtrIsValid(missingContrecPtr));
1488 heikki.linnakangas@i 6202 :CBC 12 : CreateOverwriteContrecordRecord(abortedRecPtr, missingContrecPtr, newTLI);
6203 : : }
6204 : :
6205 : : /*
6206 : : * Update full_page_writes in shared memory and write an XLOG_FPW_CHANGE
6207 : : * record before resource manager writes cleanup WAL records or checkpoint
6208 : : * record is written.
6209 : : */
1613 rhaas@postgresql.org 6210 : 939 : Insert->fullPageWrites = lastFullPageWrites;
6211 : 939 : UpdateFullPageWrites();
6212 : :
6213 : : /*
6214 : : * Emit checkpoint or end-of-recovery record in XLOG, if required.
6215 : : */
1488 heikki.linnakangas@i 6216 [ + + ]: 939 : if (performedWalRecovery)
1613 rhaas@postgresql.org 6217 : 163 : promoted = PerformRecoveryXLogAction();
6218 : :
6219 : : /*
6220 : : * If any of the critical GUCs have changed, log them before we allow
6221 : : * backends to write WAL.
6222 : : */
5800 heikki.linnakangas@i 6223 : 939 : XLogReportParameters();
6224 : :
6225 : : /* If this is archive recovery, perform post-recovery cleanup actions. */
1602 rhaas@postgresql.org 6226 [ + + ]: 939 : if (ArchiveRecoveryRequested)
1586 6227 : 55 : CleanupAfterArchiveRecovery(EndOfLogTLI, EndOfLog, newTLI);
6228 : :
6229 : : /*
6230 : : * Local WAL inserts enabled, so it's time to finish initialization of
6231 : : * commit timestamp.
6232 : : */
4120 alvherre@alvh.no-ip. 6233 : 939 : CompleteCommitTsInitialization();
6234 : :
6235 : : /*
6236 : : * Update logical decoding status in shared memory and write an
6237 : : * XLOG_LOGICAL_DECODING_STATUS_CHANGE, if necessary.
6238 : : */
82 msawada@postgresql.o 6239 :GNC 939 : UpdateLogicalDecodingStatusEndOfRecovery();
6240 : :
6241 : : /* Clean up EndOfWalRecoveryInfo data to appease Valgrind leak checking */
225 tgl@sss.pgh.pa.us 6242 [ + + ]: 939 : if (endOfRecoveryInfo->lastPage)
6243 : 917 : pfree(endOfRecoveryInfo->lastPage);
6244 : 939 : pfree(endOfRecoveryInfo->recoveryStopReason);
6245 : 939 : pfree(endOfRecoveryInfo);
6246 : :
6247 : : /*
6248 : : * All done with end-of-recovery actions.
6249 : : *
6250 : : * Now allow backends to write WAL and update the control file status in
6251 : : * consequence. SharedRecoveryState, that controls if backends can write
6252 : : * WAL, is updated while holding ControlFileLock to prevent other backends
6253 : : * to look at an inconsistent state of the control file in shared memory.
6254 : : * There is still a small window during which backends can write WAL and
6255 : : * the control file is still referring to a system not in DB_IN_PRODUCTION
6256 : : * state while looking at the on-disk control file.
6257 : : *
6258 : : * Also, we use info_lck to update SharedRecoveryState to ensure that
6259 : : * there are no race conditions concerning visibility of other recent
6260 : : * updates to shared memory.
6261 : : */
3519 peter_e@gmx.net 6262 :CBC 939 : LWLockAcquire(ControlFileLock, LW_EXCLUSIVE);
6263 : 939 : ControlFile->state = DB_IN_PRODUCTION;
6264 : :
4192 andres@anarazel.de 6265 [ - + ]: 939 : SpinLockAcquire(&XLogCtl->info_lck);
2151 michael@paquier.xyz 6266 : 939 : XLogCtl->SharedRecoveryState = RECOVERY_STATE_DONE;
4192 andres@anarazel.de 6267 : 939 : SpinLockRelease(&XLogCtl->info_lck);
6268 : :
3519 peter_e@gmx.net 6269 : 939 : UpdateControlFile();
6270 : 939 : LWLockRelease(ControlFileLock);
6271 : :
6272 : : /*
6273 : : * Wake up the checkpointer process as there might be a request to disable
6274 : : * logical decoding by concurrent slot drop.
6275 : : */
82 msawada@postgresql.o 6276 :GNC 939 : WakeupCheckpointer();
6277 : :
6278 : : /*
6279 : : * Wake up all waiters. They need to report an error that recovery was
6280 : : * ended before reaching the target LSN.
6281 : : */
69 akorotkov@postgresql 6282 : 939 : WaitLSNWakeup(WAIT_LSN_TYPE_STANDBY_REPLAY, InvalidXLogRecPtr);
6283 : 939 : WaitLSNWakeup(WAIT_LSN_TYPE_STANDBY_WRITE, InvalidXLogRecPtr);
6284 : 939 : WaitLSNWakeup(WAIT_LSN_TYPE_STANDBY_FLUSH, InvalidXLogRecPtr);
6285 : :
6286 : : /*
6287 : : * Shutdown the recovery environment. This must occur after
6288 : : * RecoverPreparedTransactions() (see notes in lock_twophase_recover())
6289 : : * and after switching SharedRecoveryState to RECOVERY_STATE_DONE so as
6290 : : * any session building a snapshot will not rely on KnownAssignedXids as
6291 : : * RecoveryInProgress() would return false at this stage. This is
6292 : : * particularly critical for prepared 2PC transactions, that would still
6293 : : * need to be included in snapshots once recovery has ended.
6294 : : */
1623 michael@paquier.xyz 6295 [ + + ]:CBC 939 : if (standbyState != STANDBY_DISABLED)
6296 : 55 : ShutdownRecoveryTransactionEnvironment();
6297 : :
6298 : : /*
6299 : : * If there were cascading standby servers connected to us, nudge any wal
6300 : : * sender processes to notice that we've been promoted.
6301 : : */
1072 andres@anarazel.de 6302 : 939 : WalSndWakeup(true, true);
6303 : :
6304 : : /*
6305 : : * If this was a promotion, request an (online) checkpoint now. This isn't
6306 : : * required for consistency, but the last restartpoint might be far back,
6307 : : * and in case of a crash, recovering from it might take a longer than is
6308 : : * appropriate now that we're not in standby mode anymore.
6309 : : */
2055 fujii@postgresql.org 6310 [ + + ]: 939 : if (promoted)
4681 simon@2ndQuadrant.co 6311 : 48 : RequestCheckpoint(CHECKPOINT_FORCE);
6234 heikki.linnakangas@i 6312 : 939 : }
6313 : :
6314 : : /*
6315 : : * Callback from PerformWalRecovery(), called when we switch from crash
6316 : : * recovery to archive recovery mode. Updates the control file accordingly.
6317 : : */
6318 : : void
1488 6319 : 1 : SwitchIntoArchiveRecovery(XLogRecPtr EndRecPtr, TimeLineID replayTLI)
6320 : : {
6321 : : /* initialize minRecoveryPoint to this record */
6322 : 1 : LWLockAcquire(ControlFileLock, LW_EXCLUSIVE);
6323 : 1 : ControlFile->state = DB_IN_ARCHIVE_RECOVERY;
6324 [ + - ]: 1 : if (ControlFile->minRecoveryPoint < EndRecPtr)
6325 : : {
6326 : 1 : ControlFile->minRecoveryPoint = EndRecPtr;
6327 : 1 : ControlFile->minRecoveryPointTLI = replayTLI;
6328 : : }
6329 : : /* update local copy */
6330 : 1 : LocalMinRecoveryPoint = ControlFile->minRecoveryPoint;
6331 : 1 : LocalMinRecoveryPointTLI = ControlFile->minRecoveryPointTLI;
6332 : :
6333 : : /*
6334 : : * The startup process can update its local copy of minRecoveryPoint from
6335 : : * this point.
6336 : : */
6337 : 1 : updateMinRecoveryPoint = true;
6338 : :
6339 : 1 : UpdateControlFile();
6340 : :
6341 : : /*
6342 : : * We update SharedRecoveryState while holding the lock on ControlFileLock
6343 : : * so both states are consistent in shared memory.
6344 : : */
6345 [ - + ]: 1 : SpinLockAcquire(&XLogCtl->info_lck);
6346 : 1 : XLogCtl->SharedRecoveryState = RECOVERY_STATE_ARCHIVE;
6347 : 1 : SpinLockRelease(&XLogCtl->info_lck);
6348 : :
6349 : 1 : LWLockRelease(ControlFileLock);
6350 : 1 : }
6351 : :
6352 : : /*
6353 : : * Callback from PerformWalRecovery(), called when we reach the end of backup.
6354 : : * Updates the control file accordingly.
6355 : : */
6356 : : void
6357 : 80 : ReachedEndOfBackup(XLogRecPtr EndRecPtr, TimeLineID tli)
6358 : : {
6359 : : /*
6360 : : * We have reached the end of base backup, as indicated by pg_control. The
6361 : : * data on disk is now consistent (unless minRecoveryPoint is further
6362 : : * ahead, which can happen if we crashed during previous recovery). Reset
6363 : : * backupStartPoint and backupEndPoint, and update minRecoveryPoint to
6364 : : * make sure we don't allow starting up at an earlier point even if
6365 : : * recovery is stopped and restarted soon after this.
6366 : : */
6367 : 80 : LWLockAcquire(ControlFileLock, LW_EXCLUSIVE);
6368 : :
6369 [ + + ]: 80 : if (ControlFile->minRecoveryPoint < EndRecPtr)
6370 : : {
6371 : 75 : ControlFile->minRecoveryPoint = EndRecPtr;
6372 : 75 : ControlFile->minRecoveryPointTLI = tli;
6373 : : }
6374 : :
6375 : 80 : ControlFile->backupStartPoint = InvalidXLogRecPtr;
6376 : 80 : ControlFile->backupEndPoint = InvalidXLogRecPtr;
6377 : 80 : ControlFile->backupEndRequired = false;
6378 : 80 : UpdateControlFile();
6379 : :
6380 : 80 : LWLockRelease(ControlFileLock);
5815 6381 : 80 : }
6382 : :
6383 : : /*
6384 : : * Perform whatever XLOG actions are necessary at end of REDO.
6385 : : *
6386 : : * The goal here is to make sure that we'll be able to recover properly if
6387 : : * we crash again. If we choose to write a checkpoint, we'll write a shutdown
6388 : : * checkpoint rather than an on-line one. This is not particularly critical,
6389 : : * but since we may be assigning a new TLI, using a shutdown checkpoint allows
6390 : : * us to have the rule that TLI only changes in shutdown checkpoints, which
6391 : : * allows some extra error checking in xlog_redo.
6392 : : */
6393 : : static bool
1614 rhaas@postgresql.org 6394 : 163 : PerformRecoveryXLogAction(void)
6395 : : {
6396 : 163 : bool promoted = false;
6397 : :
6398 : : /*
6399 : : * Perform a checkpoint to update all our recovery activity to disk.
6400 : : *
6401 : : * Note that we write a shutdown checkpoint rather than an on-line one.
6402 : : * This is not particularly critical, but since we may be assigning a new
6403 : : * TLI, using a shutdown checkpoint allows us to have the rule that TLI
6404 : : * only changes in shutdown checkpoints, which allows some extra error
6405 : : * checking in xlog_redo.
6406 : : *
6407 : : * In promotion, only create a lightweight end-of-recovery record instead
6408 : : * of a full checkpoint. A checkpoint is requested later, after we're
6409 : : * fully out of recovery mode and already accepting queries.
6410 : : */
6411 [ + + + - : 218 : if (ArchiveRecoveryRequested && IsUnderPostmaster &&
+ + ]
1488 heikki.linnakangas@i 6412 : 55 : PromoteIsTriggered())
6413 : : {
1614 rhaas@postgresql.org 6414 : 48 : promoted = true;
6415 : :
6416 : : /*
6417 : : * Insert a special WAL record to mark the end of recovery, since we
6418 : : * aren't doing a checkpoint. That means that the checkpointer process
6419 : : * may likely be in the middle of a time-smoothed restartpoint and
6420 : : * could continue to be for minutes after this. That sounds strange,
6421 : : * but the effect is roughly the same and it would be stranger to try
6422 : : * to come out of the restartpoint and then checkpoint. We request a
6423 : : * checkpoint later anyway, just for safety.
6424 : : */
6425 : 48 : CreateEndOfRecoveryRecord();
6426 : : }
6427 : : else
6428 : : {
6429 : 115 : RequestCheckpoint(CHECKPOINT_END_OF_RECOVERY |
6430 : : CHECKPOINT_FAST |
6431 : : CHECKPOINT_WAIT);
6432 : : }
6433 : :
6434 : 163 : return promoted;
6435 : : }
6436 : :
6437 : : /*
6438 : : * Is the system still in recovery?
6439 : : *
6440 : : * Unlike testing InRecovery, this works in any process that's connected to
6441 : : * shared memory.
6442 : : */
6443 : : bool
6234 heikki.linnakangas@i 6444 : 56472936 : RecoveryInProgress(void)
6445 : : {
6446 : : /*
6447 : : * We check shared state each time only until we leave recovery mode. We
6448 : : * can't re-enter recovery, so there's no need to keep checking after the
6449 : : * shared variable has once been seen false.
6450 : : */
6451 [ + + ]: 56472936 : if (!LocalRecoveryInProgress)
6452 : 54485075 : return false;
6453 : : else
6454 : : {
6455 : : /*
6456 : : * use volatile pointer to make sure we make a fresh read of the
6457 : : * shared variable.
6458 : : */
6459 : 1987861 : volatile XLogCtlData *xlogctl = XLogCtl;
6460 : :
2151 michael@paquier.xyz 6461 : 1987861 : LocalRecoveryInProgress = (xlogctl->SharedRecoveryState != RECOVERY_STATE_DONE);
6462 : :
6463 : : /*
6464 : : * Note: We don't need a memory barrier when we're still in recovery.
6465 : : * We might exit recovery immediately after return, so the caller
6466 : : * can't rely on 'true' meaning that we're still in recovery anyway.
6467 : : */
6468 : :
6234 heikki.linnakangas@i 6469 : 1987861 : return LocalRecoveryInProgress;
6470 : : }
6471 : : }
6472 : :
6473 : : /*
6474 : : * Returns current recovery state from shared memory.
6475 : : *
6476 : : * This returned state is kept consistent with the contents of the control
6477 : : * file. See details about the possible values of RecoveryState in xlog.h.
6478 : : */
6479 : : RecoveryState
2151 michael@paquier.xyz 6480 : 26686 : GetRecoveryState(void)
6481 : : {
6482 : : RecoveryState retval;
6483 : :
6484 [ - + ]: 26686 : SpinLockAcquire(&XLogCtl->info_lck);
6485 : 26686 : retval = XLogCtl->SharedRecoveryState;
6486 : 26686 : SpinLockRelease(&XLogCtl->info_lck);
6487 : :
6488 : 26686 : return retval;
6489 : : }
6490 : :
6491 : : /*
6492 : : * Is this process allowed to insert new WAL records?
6493 : : *
6494 : : * Ordinarily this is essentially equivalent to !RecoveryInProgress().
6495 : : * But we also have provisions for forcing the result "true" or "false"
6496 : : * within specific processes regardless of the global state.
6497 : : */
6498 : : bool
6106 tgl@sss.pgh.pa.us 6499 : 43142495 : XLogInsertAllowed(void)
6500 : : {
6501 : : /*
6502 : : * If value is "unconditionally true" or "unconditionally false", just
6503 : : * return it. This provides the normal fast path once recovery is known
6504 : : * done.
6505 : : */
6506 [ + + ]: 43142495 : if (LocalXLogInsertAllowed >= 0)
6507 : 42428997 : return (bool) LocalXLogInsertAllowed;
6508 : :
6509 : : /*
6510 : : * Else, must check to see if we're still in recovery.
6511 : : */
6512 [ + + ]: 713498 : if (RecoveryInProgress())
6513 : 704102 : return false;
6514 : :
6515 : : /*
6516 : : * On exit from recovery, reset to "unconditionally true", since there is
6517 : : * no need to keep checking.
6518 : : */
6519 : 9396 : LocalXLogInsertAllowed = 1;
6520 : 9396 : return true;
6521 : : }
6522 : :
6523 : : /*
6524 : : * Make XLogInsertAllowed() return true in the current process only.
6525 : : *
6526 : : * Note: it is allowed to switch LocalXLogInsertAllowed back to -1 later,
6527 : : * and even call LocalSetXLogInsertAllowed() again after that.
6528 : : *
6529 : : * Returns the previous value of LocalXLogInsertAllowed.
6530 : : */
6531 : : static int
6532 : 969 : LocalSetXLogInsertAllowed(void)
6533 : : {
1488 heikki.linnakangas@i 6534 : 969 : int oldXLogAllowed = LocalXLogInsertAllowed;
6535 : :
6106 tgl@sss.pgh.pa.us 6536 : 969 : LocalXLogInsertAllowed = 1;
6537 : :
1602 rhaas@postgresql.org 6538 : 969 : return oldXLogAllowed;
6539 : : }
6540 : :
6541 : : /*
6542 : : * Return the current Redo pointer from shared memory.
6543 : : *
6544 : : * As a side-effect, the local RedoRecPtr copy is updated.
6545 : : */
6546 : : XLogRecPtr
9208 vadim4o@yahoo.com 6547 : 218343 : GetRedoRecPtr(void)
6548 : : {
6549 : : XLogRecPtr ptr;
6550 : :
6551 : : /*
6552 : : * The possibly not up-to-date copy in XlogCtl is enough. Even if we
6553 : : * grabbed a WAL insertion lock to read the authoritative value in
6554 : : * Insert->RedoRecPtr, someone might update it just after we've released
6555 : : * the lock.
6556 : : */
4192 andres@anarazel.de 6557 [ + + ]: 218343 : SpinLockAcquire(&XLogCtl->info_lck);
6558 : 218343 : ptr = XLogCtl->RedoRecPtr;
6559 : 218343 : SpinLockRelease(&XLogCtl->info_lck);
6560 : :
4633 heikki.linnakangas@i 6561 [ + + ]: 218343 : if (RedoRecPtr < ptr)
6562 : 1592 : RedoRecPtr = ptr;
6563 : :
8766 tgl@sss.pgh.pa.us 6564 : 218343 : return RedoRecPtr;
6565 : : }
6566 : :
6567 : : /*
6568 : : * Return information needed to decide whether a modified block needs a
6569 : : * full-page image to be included in the WAL record.
6570 : : *
6571 : : * The returned values are cached copies from backend-private memory, and
6572 : : * possibly out-of-date or, indeed, uninitialized, in which case they will
6573 : : * be InvalidXLogRecPtr and false, respectively. XLogInsertRecord will
6574 : : * re-check them against up-to-date values, while holding the WAL insert lock.
6575 : : */
6576 : : void
4147 heikki.linnakangas@i 6577 : 16218120 : GetFullPageWriteInfo(XLogRecPtr *RedoRecPtr_p, bool *doPageWrites_p)
6578 : : {
6579 : 16218120 : *RedoRecPtr_p = RedoRecPtr;
6580 : 16218120 : *doPageWrites_p = doPageWrites;
6581 : 16218120 : }
6582 : :
6583 : : /*
6584 : : * GetInsertRecPtr -- Returns the current insert position.
6585 : : *
6586 : : * NOTE: The value *actually* returned is the position of the last full
6587 : : * xlog page. It lags behind the real insert position by at most 1 page.
6588 : : * For that, we don't need to scan through WAL insertion locks, and an
6589 : : * approximation is enough for the current usage of this function.
6590 : : */
6591 : : XLogRecPtr
6835 tgl@sss.pgh.pa.us 6592 : 7406 : GetInsertRecPtr(void)
6593 : : {
6594 : : XLogRecPtr recptr;
6595 : :
4192 andres@anarazel.de 6596 [ + + ]: 7406 : SpinLockAcquire(&XLogCtl->info_lck);
6597 : 7406 : recptr = XLogCtl->LogwrtRqst.Write;
6598 : 7406 : SpinLockRelease(&XLogCtl->info_lck);
6599 : :
6835 tgl@sss.pgh.pa.us 6600 : 7406 : return recptr;
6601 : : }
6602 : :
6603 : : /*
6604 : : * GetFlushRecPtr -- Returns the current flush position, ie, the last WAL
6605 : : * position known to be fsync'd to disk. This should only be used on a
6606 : : * system that is known not to be in recovery.
6607 : : */
6608 : : XLogRecPtr
1591 rhaas@postgresql.org 6609 : 204772 : GetFlushRecPtr(TimeLineID *insertTLI)
6610 : : {
1586 6611 [ - + ]: 204772 : Assert(XLogCtl->SharedRecoveryState == RECOVERY_STATE_DONE);
6612 : :
711 alvherre@alvh.no-ip. 6613 : 204772 : RefreshXLogWriteResult(LogwrtResult);
6614 : :
6615 : : /*
6616 : : * If we're writing and flushing WAL, the time line can't be changing, so
6617 : : * no lock is required.
6618 : : */
1591 rhaas@postgresql.org 6619 [ + + ]: 204772 : if (insertTLI)
1586 6620 : 25926 : *insertTLI = XLogCtl->InsertTimeLineID;
6621 : :
3715 simon@2ndQuadrant.co 6622 : 204772 : return LogwrtResult.Flush;
6623 : : }
6624 : :
6625 : : /*
6626 : : * GetWALInsertionTimeLine -- Returns the current timeline of a system that
6627 : : * is not in recovery.
6628 : : */
6629 : : TimeLineID
1591 rhaas@postgresql.org 6630 : 119655 : GetWALInsertionTimeLine(void)
6631 : : {
6632 [ - + ]: 119655 : Assert(XLogCtl->SharedRecoveryState == RECOVERY_STATE_DONE);
6633 : :
6634 : : /* Since the value can't be changing, no lock is required. */
1586 6635 : 119655 : return XLogCtl->InsertTimeLineID;
6636 : : }
6637 : :
6638 : : /*
6639 : : * GetWALInsertionTimeLineIfSet -- If the system is not in recovery, returns
6640 : : * the WAL insertion timeline; else, returns 0. Wherever possible, use
6641 : : * GetWALInsertionTimeLine() instead, since it's cheaper. Note that this
6642 : : * function decides recovery has ended as soon as the insert TLI is set, which
6643 : : * happens before we set XLogCtl->SharedRecoveryState to RECOVERY_STATE_DONE.
6644 : : */
6645 : : TimeLineID
597 6646 : 1 : GetWALInsertionTimeLineIfSet(void)
6647 : : {
6648 : : TimeLineID insertTLI;
6649 : :
6650 [ - + ]: 1 : SpinLockAcquire(&XLogCtl->info_lck);
6651 : 1 : insertTLI = XLogCtl->InsertTimeLineID;
6652 : 1 : SpinLockRelease(&XLogCtl->info_lck);
6653 : :
6654 : 1 : return insertTLI;
6655 : : }
6656 : :
6657 : : /*
6658 : : * GetLastImportantRecPtr -- Returns the LSN of the last important record
6659 : : * inserted. All records not explicitly marked as unimportant are considered
6660 : : * important.
6661 : : *
6662 : : * The LSN is determined by computing the maximum of
6663 : : * WALInsertLocks[i].lastImportantAt.
6664 : : */
6665 : : XLogRecPtr
3370 andres@anarazel.de 6666 : 1670 : GetLastImportantRecPtr(void)
6667 : : {
6668 : 1670 : XLogRecPtr res = InvalidXLogRecPtr;
6669 : : int i;
6670 : :
6671 [ + + ]: 15030 : for (i = 0; i < NUM_XLOGINSERT_LOCKS; i++)
6672 : : {
6673 : : XLogRecPtr last_important;
6674 : :
6675 : : /*
6676 : : * Need to take a lock to prevent torn reads of the LSN, which are
6677 : : * possible on some of the supported platforms. WAL insert locks only
6678 : : * support exclusive mode, so we have to use that.
6679 : : */
6680 : 13360 : LWLockAcquire(&WALInsertLocks[i].l.lock, LW_EXCLUSIVE);
6681 : 13360 : last_important = WALInsertLocks[i].l.lastImportantAt;
6682 : 13360 : LWLockRelease(&WALInsertLocks[i].l.lock);
6683 : :
6684 [ + + ]: 13360 : if (res < last_important)
6685 : 2896 : res = last_important;
6686 : : }
6687 : :
6688 : 1670 : return res;
6689 : : }
6690 : :
6691 : : /*
6692 : : * Get the time and LSN of the last xlog segment switch
6693 : : */
6694 : : pg_time_t
3370 andres@anarazel.de 6695 :UBC 0 : GetLastSegSwitchData(XLogRecPtr *lastSwitchLSN)
6696 : : {
6697 : : pg_time_t result;
6698 : :
6699 : : /* Need WALWriteLock, but shared lock is sufficient */
7150 tgl@sss.pgh.pa.us 6700 : 0 : LWLockAcquire(WALWriteLock, LW_SHARED);
4624 heikki.linnakangas@i 6701 : 0 : result = XLogCtl->lastSegSwitchTime;
3370 andres@anarazel.de 6702 : 0 : *lastSwitchLSN = XLogCtl->lastSegSwitchLSN;
7150 tgl@sss.pgh.pa.us 6703 : 0 : LWLockRelease(WALWriteLock);
6704 : :
6705 : 0 : return result;
6706 : : }
6707 : :
6708 : : /*
6709 : : * This must be called ONCE during postmaster or standalone-backend shutdown
6710 : : */
6711 : : void
8129 peter_e@gmx.net 6712 :CBC 693 : ShutdownXLOG(int code, Datum arg)
6713 : : {
6714 : : /*
6715 : : * We should have an aux process resource owner to use, and we should not
6716 : : * be in a transaction that's installed some other resowner.
6717 : : */
2797 tgl@sss.pgh.pa.us 6718 [ - + ]: 693 : Assert(AuxProcessResourceOwner != NULL);
6719 [ + + - + ]: 693 : Assert(CurrentResourceOwner == NULL ||
6720 : : CurrentResourceOwner == AuxProcessResourceOwner);
6721 : 693 : CurrentResourceOwner = AuxProcessResourceOwner;
6722 : :
6723 : : /* Don't be chatty in standalone mode */
4658 6724 [ + + + + ]: 693 : ereport(IsPostmasterEnvironment ? LOG : NOTICE,
6725 : : (errmsg("shutting down")));
6726 : :
6727 : : /*
6728 : : * Signal walsenders to move to stopping state.
6729 : : */
3205 andres@anarazel.de 6730 : 693 : WalSndInitStopping();
6731 : :
6732 : : /*
6733 : : * Wait for WAL senders to be in stopping state. This prevents commands
6734 : : * from writing new WAL.
6735 : : */
6736 : 693 : WalSndWaitStopping();
6737 : :
6234 heikki.linnakangas@i 6738 [ + + ]: 693 : if (RecoveryInProgress())
247 nathan@postgresql.or 6739 :GNC 58 : CreateRestartPoint(CHECKPOINT_IS_SHUTDOWN | CHECKPOINT_FAST);
6740 : : else
6741 : : {
6742 : : /*
6743 : : * If archiving is enabled, rotate the last XLOG file so that all the
6744 : : * remaining records are archived (postmaster wakes up the archiver
6745 : : * process one more time at the end of shutdown). The checkpoint
6746 : : * record will go to the next XLOG file and won't be archived (yet).
6747 : : */
1501 rhaas@postgresql.org 6748 [ + + - + :CBC 635 : if (XLogArchivingActive())
+ + ]
3370 andres@anarazel.de 6749 : 16 : RequestXLogSwitch(false);
6750 : :
247 nathan@postgresql.or 6751 :GNC 635 : CreateCheckPoint(CHECKPOINT_IS_SHUTDOWN | CHECKPOINT_FAST);
6752 : : }
9657 vadim4o@yahoo.com 6753 :CBC 693 : }
6754 : :
6755 : : /*
6756 : : * Format checkpoint request flags as a space-separated string for
6757 : : * log messages.
6758 : : */
6759 : : static const char *
24 fujii@postgresql.org 6760 :GNC 3008 : CheckpointFlagsString(int flags)
6761 : : {
6762 : : static char buf[128];
6763 : :
6764 : 24064 : snprintf(buf, sizeof(buf), "%s%s%s%s%s%s%s%s",
6765 [ + + ]: 3008 : (flags & CHECKPOINT_IS_SHUTDOWN) ? " shutdown" : "",
6766 [ + + ]: 3008 : (flags & CHECKPOINT_END_OF_RECOVERY) ? " end-of-recovery" : "",
6767 [ + + ]: 3008 : (flags & CHECKPOINT_FAST) ? " fast" : "",
6768 [ + + ]: 3008 : (flags & CHECKPOINT_FORCE) ? " force" : "",
6769 [ + + ]: 3008 : (flags & CHECKPOINT_WAIT) ? " wait" : "",
6770 [ + + ]: 3008 : (flags & CHECKPOINT_CAUSE_XLOG) ? " wal" : "",
6771 [ - + ]: 3008 : (flags & CHECKPOINT_CAUSE_TIME) ? " time" : "",
6772 [ + + ]: 3008 : (flags & CHECKPOINT_FLUSH_UNLOGGED) ? " flush-unlogged" : "");
6773 : :
6774 : 3008 : return buf;
6775 : : }
6776 : :
6777 : : /*
6778 : : * Log start of a checkpoint.
6779 : : */
6780 : : static void
6234 heikki.linnakangas@i 6781 :CBC 1504 : LogCheckpointStart(int flags, bool restartpoint)
6782 : : {
1927 peter@eisentraut.org 6783 [ + + ]: 1504 : if (restartpoint)
6784 [ + - - + : 204 : ereport(LOG,
- + + + +
+ + + + +
- + + + ]
6785 : : /* translator: the placeholder shows checkpoint options */
6786 : : (errmsg("restartpoint starting:%s",
6787 : : CheckpointFlagsString(flags))));
6788 : : else
6789 [ + - + + : 1300 : ereport(LOG,
- + + + +
+ + + + +
+ + + + ]
6790 : : /* translator: the placeholder shows checkpoint options */
6791 : : (errmsg("checkpoint starting:%s",
6792 : : CheckpointFlagsString(flags))));
6833 tgl@sss.pgh.pa.us 6793 : 1504 : }
6794 : :
6795 : : /*
6796 : : * Log end of a checkpoint.
6797 : : */
6798 : : static void
24 fujii@postgresql.org 6799 :GNC 1802 : LogCheckpointEnd(bool restartpoint, int flags)
6800 : : {
6801 : : long write_msecs,
6802 : : sync_msecs,
6803 : : total_msecs,
6804 : : longest_msecs,
6805 : : average_msecs;
6806 : : uint64 average_sync_time;
6807 : :
6833 tgl@sss.pgh.pa.us 6808 :CBC 1802 : CheckpointStats.ckpt_end_t = GetCurrentTimestamp();
6809 : :
1951 6810 : 1802 : write_msecs = TimestampDifferenceMilliseconds(CheckpointStats.ckpt_write_t,
6811 : : CheckpointStats.ckpt_sync_t);
6812 : :
6813 : 1802 : sync_msecs = TimestampDifferenceMilliseconds(CheckpointStats.ckpt_sync_t,
6814 : : CheckpointStats.ckpt_sync_end_t);
6815 : :
6816 : : /* Accumulate checkpoint timing summary data, in milliseconds. */
867 michael@paquier.xyz 6817 : 1802 : PendingCheckpointerStats.write_time += write_msecs;
6818 : 1802 : PendingCheckpointerStats.sync_time += sync_msecs;
6819 : :
6820 : : /*
6821 : : * All of the published timing statistics are accounted for. Only
6822 : : * continue if a log message is to be written.
6823 : : */
5092 rhaas@postgresql.org 6824 [ + + ]: 1802 : if (!log_checkpoints)
6825 : 298 : return;
6826 : :
1951 tgl@sss.pgh.pa.us 6827 : 1504 : total_msecs = TimestampDifferenceMilliseconds(CheckpointStats.ckpt_start_t,
6828 : : CheckpointStats.ckpt_end_t);
6829 : :
6830 : : /*
6831 : : * Timing values returned from CheckpointStats are in microseconds.
6832 : : * Convert to milliseconds for consistent printing.
6833 : : */
6834 : 1504 : longest_msecs = (long) ((CheckpointStats.ckpt_longest_sync + 999) / 1000);
6835 : :
5570 rhaas@postgresql.org 6836 : 1504 : average_sync_time = 0;
5453 bruce@momjian.us 6837 [ - + ]: 1504 : if (CheckpointStats.ckpt_sync_rels > 0)
5570 rhaas@postgresql.org 6838 :UBC 0 : average_sync_time = CheckpointStats.ckpt_agg_sync_time /
6839 : 0 : CheckpointStats.ckpt_sync_rels;
1951 tgl@sss.pgh.pa.us 6840 :CBC 1504 : average_msecs = (long) ((average_sync_time + 999) / 1000);
6841 : :
6842 : : /*
6843 : : * ControlFileLock is not required to see ControlFile->checkPoint and
6844 : : * ->checkPointCopy here as we are the only updator of those variables at
6845 : : * this moment.
6846 : : */
1927 peter@eisentraut.org 6847 [ + + ]: 1504 : if (restartpoint)
6848 [ + - ]: 204 : ereport(LOG,
6849 : : (errmsg("restartpoint complete:%s: wrote %d buffers (%.1f%%), "
6850 : : "wrote %d SLRU buffers; %d WAL file(s) added, "
6851 : : "%d removed, %d recycled; write=%ld.%03d s, "
6852 : : "sync=%ld.%03d s, total=%ld.%03d s; sync files=%d, "
6853 : : "longest=%ld.%03d s, average=%ld.%03d s; distance=%d kB, "
6854 : : "estimate=%d kB; lsn=%X/%08X, redo lsn=%X/%08X",
6855 : : CheckpointFlagsString(flags),
6856 : : CheckpointStats.ckpt_bufs_written,
6857 : : (double) CheckpointStats.ckpt_bufs_written * 100 / NBuffers,
6858 : : CheckpointStats.ckpt_slru_written,
6859 : : CheckpointStats.ckpt_segs_added,
6860 : : CheckpointStats.ckpt_segs_removed,
6861 : : CheckpointStats.ckpt_segs_recycled,
6862 : : write_msecs / 1000, (int) (write_msecs % 1000),
6863 : : sync_msecs / 1000, (int) (sync_msecs % 1000),
6864 : : total_msecs / 1000, (int) (total_msecs % 1000),
6865 : : CheckpointStats.ckpt_sync_rels,
6866 : : longest_msecs / 1000, (int) (longest_msecs % 1000),
6867 : : average_msecs / 1000, (int) (average_msecs % 1000),
6868 : : (int) (PrevCheckPointDistance / 1024.0),
6869 : : (int) (CheckPointDistanceEstimate / 1024.0),
6870 : : LSN_FORMAT_ARGS(ControlFile->checkPoint),
6871 : : LSN_FORMAT_ARGS(ControlFile->checkPointCopy.redo))));
6872 : : else
6873 [ + - ]: 1300 : ereport(LOG,
6874 : : (errmsg("checkpoint complete:%s: wrote %d buffers (%.1f%%), "
6875 : : "wrote %d SLRU buffers; %d WAL file(s) added, "
6876 : : "%d removed, %d recycled; write=%ld.%03d s, "
6877 : : "sync=%ld.%03d s, total=%ld.%03d s; sync files=%d, "
6878 : : "longest=%ld.%03d s, average=%ld.%03d s; distance=%d kB, "
6879 : : "estimate=%d kB; lsn=%X/%08X, redo lsn=%X/%08X",
6880 : : CheckpointFlagsString(flags),
6881 : : CheckpointStats.ckpt_bufs_written,
6882 : : (double) CheckpointStats.ckpt_bufs_written * 100 / NBuffers,
6883 : : CheckpointStats.ckpt_slru_written,
6884 : : CheckpointStats.ckpt_segs_added,
6885 : : CheckpointStats.ckpt_segs_removed,
6886 : : CheckpointStats.ckpt_segs_recycled,
6887 : : write_msecs / 1000, (int) (write_msecs % 1000),
6888 : : sync_msecs / 1000, (int) (sync_msecs % 1000),
6889 : : total_msecs / 1000, (int) (total_msecs % 1000),
6890 : : CheckpointStats.ckpt_sync_rels,
6891 : : longest_msecs / 1000, (int) (longest_msecs % 1000),
6892 : : average_msecs / 1000, (int) (average_msecs % 1000),
6893 : : (int) (PrevCheckPointDistance / 1024.0),
6894 : : (int) (CheckPointDistanceEstimate / 1024.0),
6895 : : LSN_FORMAT_ARGS(ControlFile->checkPoint),
6896 : : LSN_FORMAT_ARGS(ControlFile->checkPointCopy.redo))));
6897 : : }
6898 : :
6899 : : /*
6900 : : * Update the estimate of distance between checkpoints.
6901 : : *
6902 : : * The estimate is used to calculate the number of WAL segments to keep
6903 : : * preallocated, see XLOGfileslop().
6904 : : */
6905 : : static void
4038 heikki.linnakangas@i 6906 : 1802 : UpdateCheckPointDistanceEstimate(uint64 nbytes)
6907 : : {
6908 : : /*
6909 : : * To estimate the number of segments consumed between checkpoints, keep a
6910 : : * moving average of the amount of WAL generated in previous checkpoint
6911 : : * cycles. However, if the load is bursty, with quiet periods and busy
6912 : : * periods, we want to cater for the peak load. So instead of a plain
6913 : : * moving average, let the average decline slowly if the previous cycle
6914 : : * used less WAL than estimated, but bump it up immediately if it used
6915 : : * more.
6916 : : *
6917 : : * When checkpoints are triggered by max_wal_size, this should converge to
6918 : : * CheckpointSegments * wal_segment_size,
6919 : : *
6920 : : * Note: This doesn't pay any attention to what caused the checkpoint.
6921 : : * Checkpoints triggered manually with CHECKPOINT command, or by e.g.
6922 : : * starting a base backup, are counted the same as those created
6923 : : * automatically. The slow-decline will largely mask them out, if they are
6924 : : * not frequent. If they are frequent, it seems reasonable to count them
6925 : : * in as any others; if you issue a manual checkpoint every 5 minutes and
6926 : : * never let a timed checkpoint happen, it makes sense to base the
6927 : : * preallocation on that 5 minute interval rather than whatever
6928 : : * checkpoint_timeout is set to.
6929 : : */
6930 : 1802 : PrevCheckPointDistance = nbytes;
6931 [ + + ]: 1802 : if (CheckPointDistanceEstimate < nbytes)
6932 : 776 : CheckPointDistanceEstimate = nbytes;
6933 : : else
6934 : 1026 : CheckPointDistanceEstimate =
6935 : 1026 : (0.90 * CheckPointDistanceEstimate + 0.10 * (double) nbytes);
6833 tgl@sss.pgh.pa.us 6936 : 1802 : }
6937 : :
6938 : : /*
6939 : : * Update the ps display for a process running a checkpoint. Note that
6940 : : * this routine should not do any allocations so as it can be called
6941 : : * from a critical section.
6942 : : */
6943 : : static void
1917 michael@paquier.xyz 6944 : 3604 : update_checkpoint_display(int flags, bool restartpoint, bool reset)
6945 : : {
6946 : : /*
6947 : : * The status is reported only for end-of-recovery and shutdown
6948 : : * checkpoints or shutdown restartpoints. Updating the ps display is
6949 : : * useful in those situations as it may not be possible to rely on
6950 : : * pg_stat_activity to see the status of the checkpointer or the startup
6951 : : * process.
6952 : : */
6953 [ + + ]: 3604 : if ((flags & (CHECKPOINT_END_OF_RECOVERY | CHECKPOINT_IS_SHUTDOWN)) == 0)
6954 : 2226 : return;
6955 : :
6956 [ + + ]: 1378 : if (reset)
6957 : 689 : set_ps_display("");
6958 : : else
6959 : : {
6960 : : char activitymsg[128];
6961 : :
6962 [ + + ]: 2067 : snprintf(activitymsg, sizeof(activitymsg), "performing %s%s%s",
6963 [ + + ]: 689 : (flags & CHECKPOINT_END_OF_RECOVERY) ? "end-of-recovery " : "",
6964 [ + + ]: 689 : (flags & CHECKPOINT_IS_SHUTDOWN) ? "shutdown " : "",
6965 : : restartpoint ? "restartpoint" : "checkpoint");
6966 : 689 : set_ps_display(activitymsg);
6967 : : }
6968 : : }
6969 : :
6970 : :
6971 : : /*
6972 : : * Perform a checkpoint --- either during shutdown, or on-the-fly
6973 : : *
6974 : : * flags is a bitwise OR of the following:
6975 : : * CHECKPOINT_IS_SHUTDOWN: checkpoint is for database shutdown.
6976 : : * CHECKPOINT_END_OF_RECOVERY: checkpoint is for end of WAL recovery.
6977 : : * CHECKPOINT_FAST: finish the checkpoint ASAP, ignoring
6978 : : * checkpoint_completion_target parameter.
6979 : : * CHECKPOINT_FORCE: force a checkpoint even if no XLOG activity has occurred
6980 : : * since the last one (implied by CHECKPOINT_IS_SHUTDOWN or
6981 : : * CHECKPOINT_END_OF_RECOVERY).
6982 : : * CHECKPOINT_FLUSH_UNLOGGED: also flush buffers of unlogged tables.
6983 : : *
6984 : : * Note: flags contains other bits, of interest here only for logging purposes.
6985 : : * In particular note that this routine is synchronous and does not pay
6986 : : * attention to CHECKPOINT_WAIT.
6987 : : *
6988 : : * If !shutdown then we are writing an online checkpoint. An XLOG_CHECKPOINT_REDO
6989 : : * record is inserted into WAL at the logical location of the checkpoint, before
6990 : : * flushing anything to disk, and when the checkpoint is eventually completed,
6991 : : * and it is from this point that WAL replay will begin in the case of a recovery
6992 : : * from this checkpoint. Once everything is written to disk, an
6993 : : * XLOG_CHECKPOINT_ONLINE record is written to complete the checkpoint, and
6994 : : * points back to the earlier XLOG_CHECKPOINT_REDO record. This mechanism allows
6995 : : * other write-ahead log records to be written while the checkpoint is in
6996 : : * progress, but we must be very careful about order of operations. This function
6997 : : * may take many minutes to execute on a busy system.
6998 : : *
6999 : : * On the other hand, when shutdown is true, concurrent insertion into the
7000 : : * write-ahead log is impossible, so there is no need for two separate records.
7001 : : * In this case, we only insert an XLOG_CHECKPOINT_SHUTDOWN record, and it's
7002 : : * both the record marking the completion of the checkpoint and the location
7003 : : * from which WAL replay would begin if needed.
7004 : : *
7005 : : * Returns true if a new checkpoint was performed, or false if it was skipped
7006 : : * because the system was idle.
7007 : : */
7008 : : bool
6835 tgl@sss.pgh.pa.us 7009 : 1600 : CreateCheckPoint(int flags)
7010 : : {
7011 : : bool shutdown;
7012 : : CheckPoint checkPoint;
7013 : : XLogRecPtr recptr;
7014 : : XLogSegNo _logSegNo;
9468 bruce@momjian.us 7015 : 1600 : XLogCtlInsert *Insert = &XLogCtl->Insert;
7016 : : uint32 freespace;
7017 : : XLogRecPtr PriorRedoPtr;
7018 : : XLogRecPtr last_important_lsn;
7019 : : VirtualTransactionId *vxids;
7020 : : int nvxids;
1602 rhaas@postgresql.org 7021 : 1600 : int oldXLogAllowed = 0;
7022 : :
7023 : : /*
7024 : : * An end-of-recovery checkpoint is really a shutdown checkpoint, just
7025 : : * issued at a different time.
7026 : : */
6106 tgl@sss.pgh.pa.us 7027 [ + + ]: 1600 : if (flags & (CHECKPOINT_IS_SHUTDOWN | CHECKPOINT_END_OF_RECOVERY))
6107 heikki.linnakangas@i 7028 : 665 : shutdown = true;
7029 : : else
7030 : 935 : shutdown = false;
7031 : :
7032 : : /* sanity check */
6106 tgl@sss.pgh.pa.us 7033 [ + + - + ]: 1600 : if (RecoveryInProgress() && (flags & CHECKPOINT_END_OF_RECOVERY) == 0)
6106 tgl@sss.pgh.pa.us 7034 [ # # ]:UBC 0 : elog(ERROR, "can't create a checkpoint during recovery");
7035 : :
7036 : : /*
7037 : : * Prepare to accumulate statistics.
7038 : : *
7039 : : * Note: because it is possible for log_checkpoints to change while a
7040 : : * checkpoint proceeds, we always accumulate stats, even if
7041 : : * log_checkpoints is currently off.
7042 : : */
6833 tgl@sss.pgh.pa.us 7043 [ + - + - :CBC 17600 : MemSet(&CheckpointStats, 0, sizeof(CheckpointStats));
+ - + - +
+ ]
7044 : 1600 : CheckpointStats.ckpt_start_t = GetCurrentTimestamp();
7045 : :
7046 : : /*
7047 : : * Let smgr prepare for checkpoint; this has to happen outside the
7048 : : * critical section and before we determine the REDO pointer. Note that
7049 : : * smgr must not do anything that'd have to be undone if we decide no
7050 : : * checkpoint is needed.
7051 : : */
1460 tmunro@postgresql.or 7052 : 1600 : SyncPreCheckpoint();
7053 : :
7054 : : /* Run these points outside the critical section. */
89 michael@paquier.xyz 7055 :GNC 1600 : INJECTION_POINT("create-checkpoint-initial", NULL);
7056 : 1600 : INJECTION_POINT_LOAD("create-checkpoint-run");
7057 : :
7058 : : /*
7059 : : * Use a critical section to force system panic if we have trouble.
7060 : : */
8933 tgl@sss.pgh.pa.us 7061 :CBC 1600 : START_CRIT_SECTION();
7062 : :
9666 vadim4o@yahoo.com 7063 [ + + ]: 1600 : if (shutdown)
7064 : : {
6234 heikki.linnakangas@i 7065 : 665 : LWLockAcquire(ControlFileLock, LW_EXCLUSIVE);
9666 vadim4o@yahoo.com 7066 : 665 : ControlFile->state = DB_SHUTDOWNING;
7067 : 665 : UpdateControlFile();
6234 heikki.linnakangas@i 7068 : 665 : LWLockRelease(ControlFileLock);
7069 : : }
7070 : :
7071 : : /* Begin filling in the checkpoint WAL record */
8333 tgl@sss.pgh.pa.us 7072 [ + - + - : 20800 : MemSet(&checkPoint, 0, sizeof(checkPoint));
+ - + - +
+ ]
6601 7073 : 1600 : checkPoint.time = (pg_time_t) time(NULL);
7074 : :
7075 : : /*
7076 : : * For Hot Standby, derive the oldestActiveXid before we fix the redo
7077 : : * pointer. This allows us to begin accumulating changes to assemble our
7078 : : * starting snapshot of locks and transactions.
7079 : : */
5247 simon@2ndQuadrant.co 7080 [ + + + + ]: 1600 : if (!shutdown && XLogStandbyInfoActive())
235 akapila@postgresql.o 7081 :GNC 907 : checkPoint.oldestActiveXid = GetOldestActiveTransactionId(false, true);
7082 : : else
5247 simon@2ndQuadrant.co 7083 :CBC 693 : checkPoint.oldestActiveXid = InvalidTransactionId;
7084 : :
7085 : : /*
7086 : : * Get location of last important record before acquiring insert locks (as
7087 : : * GetLastImportantRecPtr() also locks WAL locks).
7088 : : */
3370 andres@anarazel.de 7089 : 1600 : last_important_lsn = GetLastImportantRecPtr();
7090 : :
7091 : : /*
7092 : : * If this isn't a shutdown or forced checkpoint, and if there has been no
7093 : : * WAL activity requiring a checkpoint, skip it. The idea here is to
7094 : : * avoid inserting duplicate checkpoints when the system is idle.
7095 : : */
6107 heikki.linnakangas@i 7096 [ + + ]: 1600 : if ((flags & (CHECKPOINT_IS_SHUTDOWN | CHECKPOINT_END_OF_RECOVERY |
7097 : : CHECKPOINT_FORCE)) == 0)
7098 : : {
3370 andres@anarazel.de 7099 [ + + ]: 196 : if (last_important_lsn == ControlFile->checkPoint)
7100 : : {
9133 tgl@sss.pgh.pa.us 7101 [ - + ]:GBC 2 : END_CRIT_SECTION();
3370 andres@anarazel.de 7102 [ - + ]: 2 : ereport(DEBUG1,
7103 : : (errmsg_internal("checkpoint skipped because system is idle")));
531 fujii@postgresql.org 7104 : 2 : return false;
7105 : : }
7106 : : }
7107 : :
7108 : : /*
7109 : : * An end-of-recovery checkpoint is created before anyone is allowed to
7110 : : * write WAL. To allow us to write the checkpoint record, temporarily
7111 : : * enable XLogInsertAllowed.
7112 : : */
6044 heikki.linnakangas@i 7113 [ + + ]:CBC 1598 : if (flags & CHECKPOINT_END_OF_RECOVERY)
1602 rhaas@postgresql.org 7114 : 30 : oldXLogAllowed = LocalSetXLogInsertAllowed();
7115 : :
1586 7116 : 1598 : checkPoint.ThisTimeLineID = XLogCtl->InsertTimeLineID;
4780 heikki.linnakangas@i 7117 [ + + ]: 1598 : if (flags & CHECKPOINT_END_OF_RECOVERY)
7118 : 30 : checkPoint.PrevTimeLineID = XLogCtl->PrevTimeLineID;
7119 : : else
1591 rhaas@postgresql.org 7120 : 1568 : checkPoint.PrevTimeLineID = checkPoint.ThisTimeLineID;
7121 : :
7122 : : /*
7123 : : * We must block concurrent insertions while examining insert state.
7124 : : */
878 7125 : 1598 : WALInsertLockAcquireExclusive();
7126 : :
7127 : 1598 : checkPoint.fullPageWrites = Insert->fullPageWrites;
605 7128 : 1598 : checkPoint.wal_level = wal_level;
7129 : :
878 7130 [ + + ]: 1598 : if (shutdown)
7131 : : {
7132 : 665 : XLogRecPtr curInsert = XLogBytePosToRecPtr(Insert->CurrBytePos);
7133 : :
7134 : : /*
7135 : : * Compute new REDO record ptr = location of next XLOG record.
7136 : : *
7137 : : * Since this is a shutdown checkpoint, there can't be any concurrent
7138 : : * WAL insertion.
7139 : : */
7140 [ + - ]: 665 : freespace = INSERT_FREESPACE(curInsert);
7141 [ - + ]: 665 : if (freespace == 0)
7142 : : {
878 rhaas@postgresql.org 7143 [ # # ]:UBC 0 : if (XLogSegmentOffset(curInsert, wal_segment_size) == 0)
7144 : 0 : curInsert += SizeOfXLogLongPHD;
7145 : : else
7146 : 0 : curInsert += SizeOfXLogShortPHD;
7147 : : }
878 rhaas@postgresql.org 7148 :CBC 665 : checkPoint.redo = curInsert;
7149 : :
7150 : : /*
7151 : : * Here we update the shared RedoRecPtr for future XLogInsert calls;
7152 : : * this must be done while holding all the insertion locks.
7153 : : *
7154 : : * Note: if we fail to complete the checkpoint, RedoRecPtr will be
7155 : : * left pointing past where it really needs to point. This is okay;
7156 : : * the only consequence is that XLogInsert might back up whole buffers
7157 : : * that it didn't really need to. We can't postpone advancing
7158 : : * RedoRecPtr because XLogInserts that happen while we are dumping
7159 : : * buffers must assume that their buffer changes are not included in
7160 : : * the checkpoint.
7161 : : */
7162 : 665 : RedoRecPtr = XLogCtl->Insert.RedoRecPtr = checkPoint.redo;
7163 : : }
7164 : :
7165 : : /*
7166 : : * Now we can release the WAL insertion locks, allowing other xacts to
7167 : : * proceed while we are flushing disk buffers.
7168 : : */
4377 heikki.linnakangas@i 7169 : 1598 : WALInsertLockRelease();
7170 : :
7171 : : /*
7172 : : * If this is an online checkpoint, we have not yet determined the redo
7173 : : * point. We do so now by inserting the special XLOG_CHECKPOINT_REDO
7174 : : * record; the LSN at which it starts becomes the new redo pointer. We
7175 : : * don't do this for a shutdown checkpoint, because in that case no WAL
7176 : : * can be written between the redo point and the insertion of the
7177 : : * checkpoint record itself, so the checkpoint record itself serves to
7178 : : * mark the redo point.
7179 : : */
878 rhaas@postgresql.org 7180 [ + + ]: 1598 : if (!shutdown)
7181 : : {
7182 : : /* Include WAL level in record for WAL summarizer's benefit. */
7183 : 933 : XLogBeginInsert();
397 peter@eisentraut.org 7184 : 933 : XLogRegisterData(&wal_level, sizeof(wal_level));
878 rhaas@postgresql.org 7185 : 933 : (void) XLogInsert(RM_XLOG_ID, XLOG_CHECKPOINT_REDO);
7186 : :
7187 : : /*
7188 : : * XLogInsertRecord will have updated XLogCtl->Insert.RedoRecPtr in
7189 : : * shared memory and RedoRecPtr in backend-local memory, but we need
7190 : : * to copy that into the record that will be inserted when the
7191 : : * checkpoint is complete.
7192 : : */
7193 : 933 : checkPoint.redo = RedoRecPtr;
7194 : : }
7195 : :
7196 : : /* Update the info_lck-protected copy of RedoRecPtr as well */
4192 andres@anarazel.de 7197 [ - + ]: 1598 : SpinLockAcquire(&XLogCtl->info_lck);
7198 : 1598 : XLogCtl->RedoRecPtr = checkPoint.redo;
7199 : 1598 : SpinLockRelease(&XLogCtl->info_lck);
7200 : :
7201 : : /*
7202 : : * If enabled, log checkpoint start. We postpone this until now so as not
7203 : : * to log anything if we decided to skip the checkpoint.
7204 : : */
6833 tgl@sss.pgh.pa.us 7205 [ + + ]: 1598 : if (log_checkpoints)
6234 heikki.linnakangas@i 7206 : 1300 : LogCheckpointStart(flags, false);
7207 : :
89 michael@paquier.xyz 7208 :GNC 1598 : INJECTION_POINT_CACHED("create-checkpoint-run", NULL);
7209 : :
7210 : : /* Update the process title */
1917 michael@paquier.xyz 7211 :CBC 1598 : update_checkpoint_display(flags, false, false);
7212 : :
7213 : : TRACE_POSTGRESQL_CHECKPOINT_START(flags);
7214 : :
7215 : : /*
7216 : : * Get the other info we need for the checkpoint record.
7217 : : *
7218 : : * We don't need to save oldestClogXid in the checkpoint, it only matters
7219 : : * for the short period in which clog is being truncated, and if we crash
7220 : : * during that we'll redo the clog truncation and fix up oldestClogXid
7221 : : * there.
7222 : : */
4363 heikki.linnakangas@i 7223 : 1598 : LWLockAcquire(XidGenLock, LW_SHARED);
828 7224 : 1598 : checkPoint.nextXid = TransamVariables->nextXid;
7225 : 1598 : checkPoint.oldestXid = TransamVariables->oldestXid;
7226 : 1598 : checkPoint.oldestXidDB = TransamVariables->oldestXidDB;
4363 7227 : 1598 : LWLockRelease(XidGenLock);
7228 : :
4120 alvherre@alvh.no-ip. 7229 : 1598 : LWLockAcquire(CommitTsLock, LW_SHARED);
828 heikki.linnakangas@i 7230 : 1598 : checkPoint.oldestCommitTsXid = TransamVariables->oldestCommitTsXid;
7231 : 1598 : checkPoint.newestCommitTsXid = TransamVariables->newestCommitTsXid;
4120 alvherre@alvh.no-ip. 7232 : 1598 : LWLockRelease(CommitTsLock);
7233 : :
4363 heikki.linnakangas@i 7234 : 1598 : LWLockAcquire(OidGenLock, LW_SHARED);
828 7235 : 1598 : checkPoint.nextOid = TransamVariables->nextOid;
4363 7236 [ + + ]: 1598 : if (!shutdown)
828 7237 : 933 : checkPoint.nextOid += TransamVariables->oidCount;
4363 7238 : 1598 : LWLockRelease(OidGenLock);
7239 : :
82 msawada@postgresql.o 7240 :GNC 1598 : checkPoint.logicalDecodingEnabled = IsLogicalDecodingEnabled();
7241 : :
4363 heikki.linnakangas@i 7242 :CBC 1598 : MultiXactGetCheckptMulti(shutdown,
7243 : : &checkPoint.nextMulti,
7244 : : &checkPoint.nextMultiOffset,
7245 : : &checkPoint.oldestMulti,
7246 : : &checkPoint.oldestMultiDB);
7247 : :
7248 : : /*
7249 : : * Having constructed the checkpoint record, ensure all shmem disk buffers
7250 : : * and commit-log buffers are flushed to disk.
7251 : : *
7252 : : * This I/O could fail for various reasons. If so, we will fail to
7253 : : * complete the checkpoint, but there is no reason to force a system
7254 : : * panic. Accordingly, exit critical section while doing it.
7255 : : */
7256 [ - + ]: 1598 : END_CRIT_SECTION();
7257 : :
7258 : : /*
7259 : : * In some cases there are groups of actions that must all occur on one
7260 : : * side or the other of a checkpoint record. Before flushing the
7261 : : * checkpoint record we must explicitly wait for any backend currently
7262 : : * performing those groups of actions.
7263 : : *
7264 : : * One example is end of transaction, so we must wait for any transactions
7265 : : * that are currently in commit critical sections. If an xact inserted
7266 : : * its commit record into XLOG just before the REDO point, then a crash
7267 : : * restart from the REDO point would not replay that record, which means
7268 : : * that our flushing had better include the xact's update of pg_xact. So
7269 : : * we wait till he's out of his commit critical section before proceeding.
7270 : : * See notes in RecordTransactionCommit().
7271 : : *
7272 : : * Because we've already released the insertion locks, this test is a bit
7273 : : * fuzzy: it is possible that we will wait for xacts we didn't really need
7274 : : * to wait for. But the delay should be short and it seems better to make
7275 : : * checkpoint take a bit longer than to hold off insertions longer than
7276 : : * necessary. (In fact, the whole reason we have this issue is that xact.c
7277 : : * does commit record XLOG insertion and clog update as two separate steps
7278 : : * protected by different locks, but again that seems best on grounds of
7279 : : * minimizing lock contention.)
7280 : : *
7281 : : * A transaction that has not yet set delayChkptFlags when we look cannot
7282 : : * be at risk, since it has not inserted its commit record yet; and one
7283 : : * that's already cleared it is not at risk either, since it's done fixing
7284 : : * clog and we will correctly flush the update below. So we cannot miss
7285 : : * any xacts we need to wait for.
7286 : : */
1452 rhaas@postgresql.org 7287 : 1598 : vxids = GetVirtualXIDsDelayingChkpt(&nvxids, DELAY_CHKPT_START);
4850 simon@2ndQuadrant.co 7288 [ + + ]: 1598 : if (nvxids > 0)
7289 : : {
7290 : : do
7291 : : {
7292 : : /*
7293 : : * Keep absorbing fsync requests while we wait. There could even
7294 : : * be a deadlock if we don't, if the process that prevents the
7295 : : * checkpoint is trying to add a request to the queue.
7296 : : */
632 heikki.linnakangas@i 7297 : 18 : AbsorbSyncRequests();
7298 : :
884 tmunro@postgresql.or 7299 : 18 : pgstat_report_wait_start(WAIT_EVENT_CHECKPOINT_DELAY_START);
6695 bruce@momjian.us 7300 : 18 : pg_usleep(10000L); /* wait for 10 msec */
884 tmunro@postgresql.or 7301 : 18 : pgstat_report_wait_end();
1452 rhaas@postgresql.org 7302 [ - + ]: 18 : } while (HaveVirtualXIDsDelayingChkpt(vxids, nvxids,
7303 : : DELAY_CHKPT_START));
7304 : : }
4850 simon@2ndQuadrant.co 7305 : 1598 : pfree(vxids);
7306 : :
6835 tgl@sss.pgh.pa.us 7307 : 1598 : CheckPointGuts(checkPoint.redo, flags);
7308 : :
1452 rhaas@postgresql.org 7309 : 1598 : vxids = GetVirtualXIDsDelayingChkpt(&nvxids, DELAY_CHKPT_COMPLETE);
7310 [ - + ]: 1598 : if (nvxids > 0)
7311 : : {
7312 : : do
7313 : : {
632 heikki.linnakangas@i 7314 :UBC 0 : AbsorbSyncRequests();
7315 : :
884 tmunro@postgresql.or 7316 : 0 : pgstat_report_wait_start(WAIT_EVENT_CHECKPOINT_DELAY_COMPLETE);
1452 rhaas@postgresql.org 7317 : 0 : pg_usleep(10000L); /* wait for 10 msec */
884 tmunro@postgresql.or 7318 : 0 : pgstat_report_wait_end();
1452 rhaas@postgresql.org 7319 [ # # ]: 0 : } while (HaveVirtualXIDsDelayingChkpt(vxids, nvxids,
7320 : : DELAY_CHKPT_COMPLETE));
7321 : : }
1452 rhaas@postgresql.org 7322 :CBC 1598 : pfree(vxids);
7323 : :
7324 : : /*
7325 : : * Take a snapshot of running transactions and write this to WAL. This
7326 : : * allows us to reconstruct the state of running transactions during
7327 : : * archive recovery, if required. Skip, if this info disabled.
7328 : : *
7329 : : * If we are shutting down, or Startup process is completing crash
7330 : : * recovery we don't need to write running xact data.
7331 : : */
5930 simon@2ndQuadrant.co 7332 [ + + + + ]: 1598 : if (!shutdown && XLogStandbyInfoActive())
4851 tgl@sss.pgh.pa.us 7333 : 905 : LogStandbySnapshot();
7334 : :
8345 7335 : 1598 : START_CRIT_SECTION();
7336 : :
7337 : : /*
7338 : : * Now insert the checkpoint record into XLOG.
7339 : : */
4133 heikki.linnakangas@i 7340 : 1598 : XLogBeginInsert();
397 peter@eisentraut.org 7341 : 1598 : XLogRegisterData(&checkPoint, sizeof(checkPoint));
9133 tgl@sss.pgh.pa.us 7342 [ + + ]: 1598 : recptr = XLogInsert(RM_XLOG_ID,
7343 : : shutdown ? XLOG_CHECKPOINT_SHUTDOWN :
7344 : : XLOG_CHECKPOINT_ONLINE);
7345 : :
7346 : 1598 : XLogFlush(recptr);
7347 : :
7348 : : /*
7349 : : * We mustn't write any new WAL after a shutdown checkpoint, or it will be
7350 : : * overwritten at next startup. No-one should even try, this just allows
7351 : : * sanity-checking. In the case of an end-of-recovery checkpoint, we want
7352 : : * to just temporarily disable writing until the system has exited
7353 : : * recovery.
7354 : : */
6106 7355 [ + + ]: 1598 : if (shutdown)
7356 : : {
7357 [ + + ]: 665 : if (flags & CHECKPOINT_END_OF_RECOVERY)
1602 rhaas@postgresql.org 7358 : 30 : LocalXLogInsertAllowed = oldXLogAllowed;
7359 : : else
5861 bruce@momjian.us 7360 : 635 : LocalXLogInsertAllowed = 0; /* never again write WAL */
7361 : : }
7362 : :
7363 : : /*
7364 : : * We now have ProcLastRecPtr = start of actual checkpoint record, recptr
7365 : : * = end of actual checkpoint record.
7366 : : */
4825 alvherre@alvh.no-ip. 7367 [ + + - + ]: 1598 : if (shutdown && checkPoint.redo != ProcLastRecPtr)
8273 tgl@sss.pgh.pa.us 7368 [ # # ]:UBC 0 : ereport(PANIC,
7369 : : (errmsg("concurrent write-ahead log activity while database system is shutting down")));
7370 : :
7371 : : /*
7372 : : * Remember the prior checkpoint's redo ptr for
7373 : : * UpdateCheckPointDistanceEstimate()
7374 : : */
4038 heikki.linnakangas@i 7375 :CBC 1598 : PriorRedoPtr = ControlFile->checkPointCopy.redo;
7376 : :
7377 : : /*
7378 : : * Update the control file.
7379 : : */
8933 tgl@sss.pgh.pa.us 7380 : 1598 : LWLockAcquire(ControlFileLock, LW_EXCLUSIVE);
9666 vadim4o@yahoo.com 7381 [ + + ]: 1598 : if (shutdown)
7382 : 665 : ControlFile->state = DB_SHUTDOWNED;
9133 tgl@sss.pgh.pa.us 7383 : 1598 : ControlFile->checkPoint = ProcLastRecPtr;
7384 : 1598 : ControlFile->checkPointCopy = checkPoint;
7385 : : /* crash recovery should always recover to the end of WAL */
4826 alvherre@alvh.no-ip. 7386 : 1598 : ControlFile->minRecoveryPoint = InvalidXLogRecPtr;
4849 heikki.linnakangas@i 7387 : 1598 : ControlFile->minRecoveryPointTLI = 0;
7388 : :
7389 : : /*
7390 : : * Persist unloggedLSN value. It's reset on crash recovery, so this goes
7391 : : * unused on non-shutdown checkpoints, but seems useful to store it always
7392 : : * for debugging purposes.
7393 : : */
745 nathan@postgresql.or 7394 : 1598 : ControlFile->unloggedLSN = pg_atomic_read_membarrier_u64(&XLogCtl->unloggedLSN);
7395 : :
9666 vadim4o@yahoo.com 7396 : 1598 : UpdateControlFile();
8933 tgl@sss.pgh.pa.us 7397 : 1598 : LWLockRelease(ControlFileLock);
7398 : :
7399 : : /*
7400 : : * We are now done with critical updates; no need for system panic if we
7401 : : * have trouble while fooling with old log segments.
7402 : : */
8345 7403 [ - + ]: 1598 : END_CRIT_SECTION();
7404 : :
7405 : : /*
7406 : : * WAL summaries end when the next XLOG_CHECKPOINT_REDO or
7407 : : * XLOG_CHECKPOINT_SHUTDOWN record is reached. This is the first point
7408 : : * where (a) we're not inside of a critical section and (b) we can be
7409 : : * certain that the relevant record has been flushed to disk, which must
7410 : : * happen before it can be summarized.
7411 : : *
7412 : : * If this is a shutdown checkpoint, then this happens reasonably
7413 : : * promptly: we've only just inserted and flushed the
7414 : : * XLOG_CHECKPOINT_SHUTDOWN record. If this is not a shutdown checkpoint,
7415 : : * then this might not be very prompt at all: the XLOG_CHECKPOINT_REDO
7416 : : * record was written before we began flushing data to disk, and that
7417 : : * could be many minutes ago at this point. However, we don't XLogFlush()
7418 : : * after inserting that record, so we're not guaranteed that it's on disk
7419 : : * until after the above call that flushes the XLOG_CHECKPOINT_ONLINE
7420 : : * record.
7421 : : */
499 heikki.linnakangas@i 7422 : 1598 : WakeupWalSummarizer();
7423 : :
7424 : : /*
7425 : : * Let smgr do post-checkpoint cleanup (eg, deleting old files).
7426 : : */
2537 tmunro@postgresql.or 7427 : 1598 : SyncPostCheckpoint();
7428 : :
7429 : : /*
7430 : : * Update the average distance between checkpoints if the prior checkpoint
7431 : : * exists.
7432 : : */
129 alvherre@kurilemu.de 7433 [ + - ]:GNC 1598 : if (XLogRecPtrIsValid(PriorRedoPtr))
4038 heikki.linnakangas@i 7434 :CBC 1598 : UpdateCheckPointDistanceEstimate(RedoRecPtr - PriorRedoPtr);
7435 : :
274 akorotkov@postgresql 7436 : 1598 : INJECTION_POINT("checkpoint-before-old-wal-removal", NULL);
7437 : :
7438 : : /*
7439 : : * Delete old log files, those no longer needed for last checkpoint to
7440 : : * prevent the disk holding the xlog from growing full.
7441 : : */
2791 michael@paquier.xyz 7442 : 1598 : XLByteToSeg(RedoRecPtr, _logSegNo, wal_segment_size);
7443 : 1598 : KeepLogSeg(recptr, &_logSegNo);
389 akapila@postgresql.o 7444 [ + + ]: 1598 : if (InvalidateObsoleteReplicationSlots(RS_INVAL_WAL_REMOVED | RS_INVAL_IDLE_TIMEOUT,
7445 : : _logSegNo, InvalidOid,
7446 : : InvalidTransactionId))
7447 : : {
7448 : : /*
7449 : : * Some slots have been invalidated; recalculate the old-segment
7450 : : * horizon, starting again from RedoRecPtr.
7451 : : */
1703 alvherre@alvh.no-ip. 7452 : 4 : XLByteToSeg(RedoRecPtr, _logSegNo, wal_segment_size);
7453 : 4 : KeepLogSeg(recptr, &_logSegNo);
7454 : : }
2791 michael@paquier.xyz 7455 : 1598 : _logSegNo--;
1591 rhaas@postgresql.org 7456 : 1598 : RemoveOldXlogFiles(_logSegNo, RedoRecPtr, recptr,
7457 : : checkPoint.ThisTimeLineID);
7458 : :
7459 : : /*
7460 : : * Make more log segments if needed. (Do this after recycling old log
7461 : : * segments, since that may supply some of the needed files.)
7462 : : */
9133 tgl@sss.pgh.pa.us 7463 [ + + ]: 1598 : if (!shutdown)
1591 rhaas@postgresql.org 7464 : 933 : PreallocXlogFiles(recptr, checkPoint.ThisTimeLineID);
7465 : :
7466 : : /*
7467 : : * Truncate pg_subtrans if possible. We can throw away all data before
7468 : : * the oldest XMIN of any running transaction. No future transaction will
7469 : : * attempt to reference any pg_subtrans entry older than that (see Asserts
7470 : : * in subtrans.c). During recovery, though, we mustn't do this because
7471 : : * StartupSUBTRANS hasn't been called yet.
7472 : : */
6106 tgl@sss.pgh.pa.us 7473 [ + + ]: 1598 : if (!RecoveryInProgress())
2041 andres@anarazel.de 7474 : 1568 : TruncateSUBTRANS(GetOldestTransactionIdConsideredRunning());
7475 : :
7476 : : /* Real work is done; log and update stats. */
24 fujii@postgresql.org 7477 :GNC 1598 : LogCheckpointEnd(false, flags);
7478 : :
7479 : : /* Reset the process title */
1917 michael@paquier.xyz 7480 :CBC 1598 : update_checkpoint_display(flags, false, true);
7481 : :
7482 : : TRACE_POSTGRESQL_CHECKPOINT_DONE(CheckpointStats.ckpt_bufs_written,
7483 : : NBuffers,
7484 : : CheckpointStats.ckpt_segs_added,
7485 : : CheckpointStats.ckpt_segs_removed,
7486 : : CheckpointStats.ckpt_segs_recycled);
7487 : :
531 fujii@postgresql.org 7488 : 1598 : return true;
7489 : : }
7490 : :
7491 : : /*
7492 : : * Mark the end of recovery in WAL though without running a full checkpoint.
7493 : : * We can expect that a restartpoint is likely to be in progress as we
7494 : : * do this, though we are unwilling to wait for it to complete.
7495 : : *
7496 : : * CreateRestartPoint() allows for the case where recovery may end before
7497 : : * the restartpoint completes so there is no concern of concurrent behaviour.
7498 : : */
7499 : : static void
4793 simon@2ndQuadrant.co 7500 : 48 : CreateEndOfRecoveryRecord(void)
7501 : : {
7502 : : xl_end_of_recovery xlrec;
7503 : : XLogRecPtr recptr;
7504 : :
7505 : : /* sanity check */
7506 [ - + ]: 48 : if (!RecoveryInProgress())
4793 simon@2ndQuadrant.co 7507 [ # # ]:UBC 0 : elog(ERROR, "can only be used to end recovery");
7508 : :
4104 heikki.linnakangas@i 7509 :CBC 48 : xlrec.end_time = GetCurrentTimestamp();
605 rhaas@postgresql.org 7510 : 48 : xlrec.wal_level = wal_level;
7511 : :
4377 heikki.linnakangas@i 7512 : 48 : WALInsertLockAcquireExclusive();
1586 rhaas@postgresql.org 7513 : 48 : xlrec.ThisTimeLineID = XLogCtl->InsertTimeLineID;
4780 heikki.linnakangas@i 7514 : 48 : xlrec.PrevTimeLineID = XLogCtl->PrevTimeLineID;
4377 7515 : 48 : WALInsertLockRelease();
7516 : :
4793 simon@2ndQuadrant.co 7517 : 48 : START_CRIT_SECTION();
7518 : :
4133 heikki.linnakangas@i 7519 : 48 : XLogBeginInsert();
397 peter@eisentraut.org 7520 : 48 : XLogRegisterData(&xlrec, sizeof(xl_end_of_recovery));
4133 heikki.linnakangas@i 7521 : 48 : recptr = XLogInsert(RM_XLOG_ID, XLOG_END_OF_RECOVERY);
7522 : :
4791 simon@2ndQuadrant.co 7523 : 48 : XLogFlush(recptr);
7524 : :
7525 : : /*
7526 : : * Update the control file so that crash recovery can follow the timeline
7527 : : * changes to this point.
7528 : : */
7529 : 48 : LWLockAcquire(ControlFileLock, LW_EXCLUSIVE);
7530 : 48 : ControlFile->minRecoveryPoint = recptr;
1591 rhaas@postgresql.org 7531 : 48 : ControlFile->minRecoveryPointTLI = xlrec.ThisTimeLineID;
4791 simon@2ndQuadrant.co 7532 : 48 : UpdateControlFile();
7533 : 48 : LWLockRelease(ControlFileLock);
7534 : :
4793 7535 [ - + ]: 48 : END_CRIT_SECTION();
7536 : 48 : }
7537 : :
7538 : : /*
7539 : : * Write an OVERWRITE_CONTRECORD message.
7540 : : *
7541 : : * When on WAL replay we expect a continuation record at the start of a page
7542 : : * that is not there, recovery ends and WAL writing resumes at that point.
7543 : : * But it's wrong to resume writing new WAL back at the start of the record
7544 : : * that was broken, because downstream consumers of that WAL (physical
7545 : : * replicas) are not prepared to "rewind". So the first action after
7546 : : * finishing replay of all valid WAL must be to write a record of this type
7547 : : * at the point where the contrecord was missing; to support xlogreader
7548 : : * detecting the special case, XLP_FIRST_IS_OVERWRITE_CONTRECORD is also added
7549 : : * to the page header where the record occurs. xlogreader has an ad-hoc
7550 : : * mechanism to report metadata about the broken record, which is what we
7551 : : * use here.
7552 : : *
7553 : : * At replay time, XLP_FIRST_IS_OVERWRITE_CONTRECORD instructs xlogreader to
7554 : : * skip the record it was reading, and pass back the LSN of the skipped
7555 : : * record, so that its caller can verify (on "replay" of that record) that the
7556 : : * XLOG_OVERWRITE_CONTRECORD matches what was effectively overwritten.
7557 : : *
7558 : : * 'aborted_lsn' is the beginning position of the record that was incomplete.
7559 : : * It is included in the WAL record. 'pagePtr' and 'newTLI' point to the
7560 : : * beginning of the XLOG page where the record is to be inserted. They must
7561 : : * match the current WAL insert position, they're passed here just so that we
7562 : : * can verify that.
7563 : : */
7564 : : static XLogRecPtr
1488 heikki.linnakangas@i 7565 : 12 : CreateOverwriteContrecordRecord(XLogRecPtr aborted_lsn, XLogRecPtr pagePtr,
7566 : : TimeLineID newTLI)
7567 : : {
7568 : : xl_overwrite_contrecord xlrec;
7569 : : XLogRecPtr recptr;
7570 : : XLogPageHeader pagehdr;
7571 : : XLogRecPtr startPos;
7572 : :
7573 : : /* sanity checks */
1628 alvherre@alvh.no-ip. 7574 [ - + ]: 12 : if (!RecoveryInProgress())
1628 alvherre@alvh.no-ip. 7575 [ # # ]:UBC 0 : elog(ERROR, "can only be used at end of recovery");
1488 heikki.linnakangas@i 7576 [ - + ]:CBC 12 : if (pagePtr % XLOG_BLCKSZ != 0)
251 alvherre@kurilemu.de 7577 [ # # ]:UNC 0 : elog(ERROR, "invalid position for missing continuation record %X/%08X",
7578 : : LSN_FORMAT_ARGS(pagePtr));
7579 : :
7580 : : /* The current WAL insert position should be right after the page header */
1488 heikki.linnakangas@i 7581 :CBC 12 : startPos = pagePtr;
7582 [ + + ]: 12 : if (XLogSegmentOffset(startPos, wal_segment_size) == 0)
7583 : 1 : startPos += SizeOfXLogLongPHD;
7584 : : else
7585 : 11 : startPos += SizeOfXLogShortPHD;
7586 : 12 : recptr = GetXLogInsertRecPtr();
7587 [ - + ]: 12 : if (recptr != startPos)
251 alvherre@kurilemu.de 7588 [ # # ]:UNC 0 : elog(ERROR, "invalid WAL insert position %X/%08X for OVERWRITE_CONTRECORD",
7589 : : LSN_FORMAT_ARGS(recptr));
7590 : :
1628 alvherre@alvh.no-ip. 7591 :CBC 12 : START_CRIT_SECTION();
7592 : :
7593 : : /*
7594 : : * Initialize the XLOG page header (by GetXLogBuffer), and set the
7595 : : * XLP_FIRST_IS_OVERWRITE_CONTRECORD flag.
7596 : : *
7597 : : * No other backend is allowed to write WAL yet, so acquiring the WAL
7598 : : * insertion lock is just pro forma.
7599 : : */
1488 heikki.linnakangas@i 7600 : 12 : WALInsertLockAcquire();
7601 : 12 : pagehdr = (XLogPageHeader) GetXLogBuffer(pagePtr, newTLI);
7602 : 12 : pagehdr->xlp_info |= XLP_FIRST_IS_OVERWRITE_CONTRECORD;
7603 : 12 : WALInsertLockRelease();
7604 : :
7605 : : /*
7606 : : * Insert the XLOG_OVERWRITE_CONTRECORD record as the first record on the
7607 : : * page. We know it becomes the first record, because no other backend is
7608 : : * allowed to write WAL yet.
7609 : : */
1628 alvherre@alvh.no-ip. 7610 : 12 : XLogBeginInsert();
1488 heikki.linnakangas@i 7611 : 12 : xlrec.overwritten_lsn = aborted_lsn;
7612 : 12 : xlrec.overwrite_time = GetCurrentTimestamp();
397 peter@eisentraut.org 7613 : 12 : XLogRegisterData(&xlrec, sizeof(xl_overwrite_contrecord));
1628 alvherre@alvh.no-ip. 7614 : 12 : recptr = XLogInsert(RM_XLOG_ID, XLOG_OVERWRITE_CONTRECORD);
7615 : :
7616 : : /* check that the record was inserted to the right place */
1488 heikki.linnakangas@i 7617 [ - + ]: 12 : if (ProcLastRecPtr != startPos)
251 alvherre@kurilemu.de 7618 [ # # ]:UNC 0 : elog(ERROR, "OVERWRITE_CONTRECORD was inserted to unexpected position %X/%08X",
7619 : : LSN_FORMAT_ARGS(ProcLastRecPtr));
7620 : :
1628 alvherre@alvh.no-ip. 7621 :CBC 12 : XLogFlush(recptr);
7622 : :
7623 [ - + ]: 12 : END_CRIT_SECTION();
7624 : :
7625 : 12 : return recptr;
7626 : : }
7627 : :
7628 : : /*
7629 : : * Flush all data in shared memory to disk, and fsync
7630 : : *
7631 : : * This is the common code shared between regular checkpoints and
7632 : : * recovery restartpoints.
7633 : : */
7634 : : static void
6835 tgl@sss.pgh.pa.us 7635 : 1802 : CheckPointGuts(XLogRecPtr checkPointRedo, int flags)
7636 : : {
5880 7637 : 1802 : CheckPointRelationMap();
913 akapila@postgresql.o 7638 : 1802 : CheckPointReplicationSlots(flags & CHECKPOINT_IS_SHUTDOWN);
4395 rhaas@postgresql.org 7639 : 1802 : CheckPointSnapBuild();
7640 : 1802 : CheckPointLogicalRewriteHeap();
3973 andres@anarazel.de 7641 : 1802 : CheckPointReplicationOrigin();
7642 : :
7643 : : /* Write out all dirty data in SLRUs and the main buffer pool */
7644 : : TRACE_POSTGRESQL_BUFFER_CHECKPOINT_START(flags);
1997 tmunro@postgresql.or 7645 : 1802 : CheckpointStats.ckpt_write_t = GetCurrentTimestamp();
7646 : 1802 : CheckPointCLOG();
7647 : 1802 : CheckPointCommitTs();
7648 : 1802 : CheckPointSUBTRANS();
7649 : 1802 : CheckPointMultiXact();
7650 : 1802 : CheckPointPredicate();
7651 : 1802 : CheckPointBuffers(flags);
7652 : :
7653 : : /* Perform all queued up fsyncs */
7654 : : TRACE_POSTGRESQL_BUFFER_CHECKPOINT_SYNC_START();
7655 : 1802 : CheckpointStats.ckpt_sync_t = GetCurrentTimestamp();
7656 : 1802 : ProcessSyncRequests();
7657 : 1802 : CheckpointStats.ckpt_sync_end_t = GetCurrentTimestamp();
7658 : : TRACE_POSTGRESQL_BUFFER_CHECKPOINT_DONE();
7659 : :
7660 : : /* We deliberately delay 2PC checkpointing as long as possible */
7160 tgl@sss.pgh.pa.us 7661 : 1802 : CheckPointTwoPhase(checkPointRedo);
7662 : 1802 : }
7663 : :
7664 : : /*
7665 : : * Save a checkpoint for recovery restart if appropriate
7666 : : *
7667 : : * This function is called each time a checkpoint record is read from XLOG.
7668 : : * It must determine whether the checkpoint represents a safe restartpoint or
7669 : : * not. If so, the checkpoint record is stashed in shared memory so that
7670 : : * CreateRestartPoint can consult it. (Note that the latter function is
7671 : : * executed by the checkpointer, while this one will be executed by the
7672 : : * startup process.)
7673 : : */
7674 : : static void
1572 rhaas@postgresql.org 7675 : 734 : RecoveryRestartPoint(const CheckPoint *checkPoint, XLogReaderState *record)
7676 : : {
7677 : : /*
7678 : : * Also refrain from creating a restartpoint if we have seen any
7679 : : * references to non-existent pages. Restarting recovery from the
7680 : : * restartpoint would not see the references, so we would lose the
7681 : : * cross-check that the pages belonged to a relation that was dropped
7682 : : * later.
7683 : : */
5217 heikki.linnakangas@i 7684 [ - + ]: 734 : if (XLogHaveInvalidPages())
7685 : : {
825 michael@paquier.xyz 7686 [ # # ]:UBC 0 : elog(DEBUG2,
7687 : : "could not record restart point at %X/%08X because there are unresolved references to invalid pages",
7688 : : LSN_FORMAT_ARGS(checkPoint->redo));
5217 heikki.linnakangas@i 7689 : 0 : return;
7690 : : }
7691 : :
7692 : : /*
7693 : : * Copy the checkpoint record to shared memory, so that checkpointer can
7694 : : * work out the next time it wants to perform a restartpoint.
7695 : : */
4192 andres@anarazel.de 7696 [ - + ]:CBC 734 : SpinLockAcquire(&XLogCtl->info_lck);
1572 rhaas@postgresql.org 7697 : 734 : XLogCtl->lastCheckPointRecPtr = record->ReadRecPtr;
7698 : 734 : XLogCtl->lastCheckPointEndPtr = record->EndRecPtr;
4192 andres@anarazel.de 7699 : 734 : XLogCtl->lastCheckPoint = *checkPoint;
7700 : 734 : SpinLockRelease(&XLogCtl->info_lck);
7701 : : }
7702 : :
7703 : : /*
7704 : : * Establish a restartpoint if possible.
7705 : : *
7706 : : * This is similar to CreateCheckPoint, but is used during WAL recovery
7707 : : * to establish a point from which recovery can roll forward without
7708 : : * replaying the entire recovery log.
7709 : : *
7710 : : * Returns true if a new restartpoint was established. We can only establish
7711 : : * a restartpoint if we have replayed a safe checkpoint record since last
7712 : : * restartpoint.
7713 : : */
7714 : : bool
6234 heikki.linnakangas@i 7715 : 614 : CreateRestartPoint(int flags)
7716 : : {
7717 : : XLogRecPtr lastCheckPointRecPtr;
7718 : : XLogRecPtr lastCheckPointEndPtr;
7719 : : CheckPoint lastCheckPoint;
7720 : : XLogRecPtr PriorRedoPtr;
7721 : : XLogRecPtr receivePtr;
7722 : : XLogRecPtr replayPtr;
7723 : : TimeLineID replayTLI;
7724 : : XLogRecPtr endptr;
7725 : : XLogSegNo _logSegNo;
7726 : : TimestampTz xtime;
7727 : :
7728 : : /* Concurrent checkpoint/restartpoint cannot happen */
1406 michael@paquier.xyz 7729 [ + - - + ]: 614 : Assert(!IsUnderPostmaster || MyBackendType == B_CHECKPOINTER);
7730 : :
7731 : : /* Get a local copy of the last safe checkpoint record. */
4192 andres@anarazel.de 7732 [ - + ]: 614 : SpinLockAcquire(&XLogCtl->info_lck);
7733 : 614 : lastCheckPointRecPtr = XLogCtl->lastCheckPointRecPtr;
3426 rhaas@postgresql.org 7734 : 614 : lastCheckPointEndPtr = XLogCtl->lastCheckPointEndPtr;
4192 andres@anarazel.de 7735 : 614 : lastCheckPoint = XLogCtl->lastCheckPoint;
7736 : 614 : SpinLockRelease(&XLogCtl->info_lck);
7737 : :
7738 : : /*
7739 : : * Check that we're still in recovery mode. It's ok if we exit recovery
7740 : : * mode after this check, the restart point is valid anyway.
7741 : : */
6234 heikki.linnakangas@i 7742 [ - + ]: 614 : if (!RecoveryInProgress())
7743 : : {
6234 heikki.linnakangas@i 7744 [ # # ]:UBC 0 : ereport(DEBUG2,
7745 : : (errmsg_internal("skipping restartpoint, recovery has already ended")));
7746 : 0 : return false;
7747 : : }
7748 : :
7749 : : /*
7750 : : * If the last checkpoint record we've replayed is already our last
7751 : : * restartpoint, we can't perform a new restart point. We still update
7752 : : * minRecoveryPoint in that case, so that if this is a shutdown restart
7753 : : * point, we won't start up earlier than before. That's not strictly
7754 : : * necessary, but when hot standby is enabled, it would be rather weird if
7755 : : * the database opened up for read-only connections at a point-in-time
7756 : : * before the last shutdown. Such time travel is still possible in case of
7757 : : * immediate shutdown, though.
7758 : : *
7759 : : * We don't explicitly advance minRecoveryPoint when we do create a
7760 : : * restartpoint. It's assumed that flushing the buffers will do that as a
7761 : : * side-effect.
7762 : : */
129 alvherre@kurilemu.de 7763 [ + + ]:GNC 614 : if (!XLogRecPtrIsValid(lastCheckPointRecPtr) ||
4825 alvherre@alvh.no-ip. 7764 [ + + ]:CBC 282 : lastCheckPoint.redo <= ControlFile->checkPointCopy.redo)
7765 : : {
6234 heikki.linnakangas@i 7766 [ - + ]: 410 : ereport(DEBUG2,
7767 : : errmsg_internal("skipping restartpoint, already performed at %X/%08X",
7768 : : LSN_FORMAT_ARGS(lastCheckPoint.redo)));
7769 : :
7770 : 410 : UpdateMinRecoveryPoint(InvalidXLogRecPtr, true);
5764 rhaas@postgresql.org 7771 [ + + ]: 410 : if (flags & CHECKPOINT_IS_SHUTDOWN)
7772 : : {
7773 : 34 : LWLockAcquire(ControlFileLock, LW_EXCLUSIVE);
7774 : 34 : ControlFile->state = DB_SHUTDOWNED_IN_RECOVERY;
7775 : 34 : UpdateControlFile();
7776 : 34 : LWLockRelease(ControlFileLock);
7777 : : }
6234 heikki.linnakangas@i 7778 : 410 : return false;
7779 : : }
7780 : :
7781 : : /*
7782 : : * Update the shared RedoRecPtr so that the startup process can calculate
7783 : : * the number of segments replayed since last restartpoint, and request a
7784 : : * restartpoint if it exceeds CheckPointSegments.
7785 : : *
7786 : : * Like in CreateCheckPoint(), hold off insertions to update it, although
7787 : : * during recovery this is just pro forma, because no WAL insertions are
7788 : : * happening.
7789 : : */
4377 7790 : 204 : WALInsertLockAcquireExclusive();
4038 7791 : 204 : RedoRecPtr = XLogCtl->Insert.RedoRecPtr = lastCheckPoint.redo;
4377 7792 : 204 : WALInsertLockRelease();
7793 : :
7794 : : /* Also update the info_lck-protected copy */
4192 andres@anarazel.de 7795 [ - + ]: 204 : SpinLockAcquire(&XLogCtl->info_lck);
7796 : 204 : XLogCtl->RedoRecPtr = lastCheckPoint.redo;
7797 : 204 : SpinLockRelease(&XLogCtl->info_lck);
7798 : :
7799 : : /*
7800 : : * Prepare to accumulate statistics.
7801 : : *
7802 : : * Note: because it is possible for log_checkpoints to change while a
7803 : : * checkpoint proceeds, we always accumulate stats, even if
7804 : : * log_checkpoints is currently off.
7805 : : */
5520 rhaas@postgresql.org 7806 [ + - + - : 2244 : MemSet(&CheckpointStats, 0, sizeof(CheckpointStats));
+ - + - +
+ ]
7807 : 204 : CheckpointStats.ckpt_start_t = GetCurrentTimestamp();
7808 : :
7809 [ + - ]: 204 : if (log_checkpoints)
6234 heikki.linnakangas@i 7810 : 204 : LogCheckpointStart(flags, true);
7811 : :
7812 : : /* Update the process title */
1917 michael@paquier.xyz 7813 : 204 : update_checkpoint_display(flags, true, false);
7814 : :
6234 heikki.linnakangas@i 7815 : 204 : CheckPointGuts(lastCheckPoint.redo, flags);
7816 : :
7817 : : /*
7818 : : * This location needs to be after CheckPointGuts() to ensure that some
7819 : : * work has already happened during this checkpoint.
7820 : : */
309 michael@paquier.xyz 7821 : 204 : INJECTION_POINT("create-restart-point", NULL);
7822 : :
7823 : : /*
7824 : : * Remember the prior checkpoint's redo ptr for
7825 : : * UpdateCheckPointDistanceEstimate()
7826 : : */
4038 heikki.linnakangas@i 7827 : 204 : PriorRedoPtr = ControlFile->checkPointCopy.redo;
7828 : :
7829 : : /*
7830 : : * Update pg_control, using current time. Check that it still shows an
7831 : : * older checkpoint, else do nothing; this is a quick hack to make sure
7832 : : * nothing really bad happens if somehow we get here after the
7833 : : * end-of-recovery checkpoint.
7834 : : */
6234 7835 : 204 : LWLockAcquire(ControlFileLock, LW_EXCLUSIVE);
1406 michael@paquier.xyz 7836 [ + - ]: 204 : if (ControlFile->checkPointCopy.redo < lastCheckPoint.redo)
7837 : : {
7838 : : /*
7839 : : * Update the checkpoint information. We do this even if the cluster
7840 : : * does not show DB_IN_ARCHIVE_RECOVERY to match with the set of WAL
7841 : : * segments recycled below.
7842 : : */
6106 tgl@sss.pgh.pa.us 7843 : 204 : ControlFile->checkPoint = lastCheckPointRecPtr;
7844 : 204 : ControlFile->checkPointCopy = lastCheckPoint;
7845 : :
7846 : : /*
7847 : : * Ensure minRecoveryPoint is past the checkpoint record and update it
7848 : : * if the control file still shows DB_IN_ARCHIVE_RECOVERY. Normally,
7849 : : * this will have happened already while writing out dirty buffers,
7850 : : * but not necessarily - e.g. because no buffers were dirtied. We do
7851 : : * this because a backup performed in recovery uses minRecoveryPoint
7852 : : * to determine which WAL files must be included in the backup, and
7853 : : * the file (or files) containing the checkpoint record must be
7854 : : * included, at a minimum. Note that for an ordinary restart of
7855 : : * recovery there's no value in having the minimum recovery point any
7856 : : * earlier than this anyway, because redo will begin just after the
7857 : : * checkpoint record.
7858 : : */
1406 michael@paquier.xyz 7859 [ + - ]: 204 : if (ControlFile->state == DB_IN_ARCHIVE_RECOVERY)
7860 : : {
7861 [ + + ]: 204 : if (ControlFile->minRecoveryPoint < lastCheckPointEndPtr)
7862 : : {
7863 : 21 : ControlFile->minRecoveryPoint = lastCheckPointEndPtr;
7864 : 21 : ControlFile->minRecoveryPointTLI = lastCheckPoint.ThisTimeLineID;
7865 : :
7866 : : /* update local copy */
7867 : 21 : LocalMinRecoveryPoint = ControlFile->minRecoveryPoint;
7868 : 21 : LocalMinRecoveryPointTLI = ControlFile->minRecoveryPointTLI;
7869 : : }
7870 [ + + ]: 204 : if (flags & CHECKPOINT_IS_SHUTDOWN)
7871 : 24 : ControlFile->state = DB_SHUTDOWNED_IN_RECOVERY;
7872 : : }
6106 tgl@sss.pgh.pa.us 7873 : 204 : UpdateControlFile();
7874 : : }
6234 heikki.linnakangas@i 7875 : 204 : LWLockRelease(ControlFileLock);
7876 : :
7877 : : /*
7878 : : * Update the average distance between checkpoints/restartpoints if the
7879 : : * prior checkpoint exists.
7880 : : */
129 alvherre@kurilemu.de 7881 [ + - ]:GNC 204 : if (XLogRecPtrIsValid(PriorRedoPtr))
4038 heikki.linnakangas@i 7882 :CBC 204 : UpdateCheckPointDistanceEstimate(RedoRecPtr - PriorRedoPtr);
7883 : :
7884 : : /*
7885 : : * Delete old log files, those no longer needed for last restartpoint to
7886 : : * prevent the disk holding the xlog from growing full.
7887 : : */
2791 michael@paquier.xyz 7888 : 204 : XLByteToSeg(RedoRecPtr, _logSegNo, wal_segment_size);
7889 : :
7890 : : /*
7891 : : * Retreat _logSegNo using the current end of xlog replayed or received,
7892 : : * whichever is later.
7893 : : */
2167 tmunro@postgresql.or 7894 : 204 : receivePtr = GetWalRcvFlushRecPtr(NULL, NULL);
2791 michael@paquier.xyz 7895 : 204 : replayPtr = GetXLogReplayRecPtr(&replayTLI);
7896 : 204 : endptr = (receivePtr < replayPtr) ? replayPtr : receivePtr;
7897 : 204 : KeepLogSeg(endptr, &_logSegNo);
7898 : :
47 akapila@postgresql.o 7899 : 204 : INJECTION_POINT("restartpoint-before-slot-invalidation", NULL);
7900 : :
389 7901 [ + + ]: 204 : if (InvalidateObsoleteReplicationSlots(RS_INVAL_WAL_REMOVED | RS_INVAL_IDLE_TIMEOUT,
7902 : : _logSegNo, InvalidOid,
7903 : : InvalidTransactionId))
7904 : : {
7905 : : /*
7906 : : * Some slots have been invalidated; recalculate the old-segment
7907 : : * horizon, starting again from RedoRecPtr.
7908 : : */
1703 alvherre@alvh.no-ip. 7909 : 1 : XLByteToSeg(RedoRecPtr, _logSegNo, wal_segment_size);
7910 : 1 : KeepLogSeg(endptr, &_logSegNo);
7911 : : }
2791 michael@paquier.xyz 7912 : 204 : _logSegNo--;
7913 : :
7914 : : /*
7915 : : * Try to recycle segments on a useful timeline. If we've been promoted
7916 : : * since the beginning of this restartpoint, use the new timeline chosen
7917 : : * at end of recovery. If we're still in recovery, use the timeline we're
7918 : : * currently replaying.
7919 : : *
7920 : : * There is no guarantee that the WAL segments will be useful on the
7921 : : * current timeline; if recovery proceeds to a new timeline right after
7922 : : * this, the pre-allocated WAL segments on this timeline will not be used,
7923 : : * and will go wasted until recycled on the next restartpoint. We'll live
7924 : : * with that.
7925 : : */
1591 rhaas@postgresql.org 7926 [ - + ]: 204 : if (!RecoveryInProgress())
1586 rhaas@postgresql.org 7927 :UBC 0 : replayTLI = XLogCtl->InsertTimeLineID;
7928 : :
1591 rhaas@postgresql.org 7929 :CBC 204 : RemoveOldXlogFiles(_logSegNo, RedoRecPtr, endptr, replayTLI);
7930 : :
7931 : : /*
7932 : : * Make more log segments if needed. (Do this after recycling old log
7933 : : * segments, since that may supply some of the needed files.)
7934 : : */
7935 : 204 : PreallocXlogFiles(endptr, replayTLI);
7936 : :
7937 : : /*
7938 : : * Truncate pg_subtrans if possible. We can throw away all data before
7939 : : * the oldest XMIN of any running transaction. No future transaction will
7940 : : * attempt to reference any pg_subtrans entry older than that (see Asserts
7941 : : * in subtrans.c). When hot standby is disabled, though, we mustn't do
7942 : : * this because StartupSUBTRANS hasn't been called yet.
7943 : : */
5676 simon@2ndQuadrant.co 7944 [ + - ]: 204 : if (EnableHotStandby)
2041 andres@anarazel.de 7945 : 204 : TruncateSUBTRANS(GetOldestTransactionIdConsideredRunning());
7946 : :
7947 : : /* Real work is done; log and update stats. */
24 fujii@postgresql.org 7948 :GNC 204 : LogCheckpointEnd(true, flags);
7949 : :
7950 : : /* Reset the process title */
1917 michael@paquier.xyz 7951 :CBC 204 : update_checkpoint_display(flags, true, true);
7952 : :
5734 tgl@sss.pgh.pa.us 7953 : 204 : xtime = GetLatestXTime();
6234 heikki.linnakangas@i 7954 [ + - + - : 204 : ereport((log_checkpoints ? LOG : DEBUG2),
+ + ]
7955 : : errmsg("recovery restart point at %X/%08X",
7956 : : LSN_FORMAT_ARGS(lastCheckPoint.redo)),
7957 : : xtime ? errdetail("Last completed transaction was at log time %s.",
7958 : : timestamptz_to_str(xtime)) : 0);
7959 : :
7960 : : /*
7961 : : * Finally, execute archive_cleanup_command, if any.
7962 : : */
2667 peter_e@gmx.net 7963 [ + - - + ]: 204 : if (archiveCleanupCommand && strcmp(archiveCleanupCommand, "") != 0)
1133 michael@paquier.xyz 7964 :UBC 0 : ExecuteRecoveryCommand(archiveCleanupCommand,
7965 : : "archive_cleanup_command",
7966 : : false,
7967 : : WAIT_EVENT_ARCHIVE_CLEANUP_COMMAND);
7968 : :
6234 heikki.linnakangas@i 7969 :CBC 204 : return true;
7970 : : }
7971 : :
7972 : : /*
7973 : : * Report availability of WAL for the given target LSN
7974 : : * (typically a slot's restart_lsn)
7975 : : *
7976 : : * Returns one of the following enum values:
7977 : : *
7978 : : * * WALAVAIL_RESERVED means targetLSN is available and it is in the range of
7979 : : * max_wal_size.
7980 : : *
7981 : : * * WALAVAIL_EXTENDED means it is still available by preserving extra
7982 : : * segments beyond max_wal_size. If max_slot_wal_keep_size is smaller
7983 : : * than max_wal_size, this state is not returned.
7984 : : *
7985 : : * * WALAVAIL_UNRESERVED means it is being lost and the next checkpoint will
7986 : : * remove reserved segments. The walsender using this slot may return to the
7987 : : * above.
7988 : : *
7989 : : * * WALAVAIL_REMOVED means it has been removed. A replication stream on
7990 : : * a slot with this LSN cannot continue. (Any associated walsender
7991 : : * processes should have been terminated already.)
7992 : : *
7993 : : * * WALAVAIL_INVALID_LSN means the slot hasn't been set to reserve WAL.
7994 : : */
7995 : : WALAvailability
2168 alvherre@alvh.no-ip. 7996 : 618 : GetWALAvailability(XLogRecPtr targetLSN)
7997 : : {
7998 : : XLogRecPtr currpos; /* current write LSN */
7999 : : XLogSegNo currSeg; /* segid of currpos */
8000 : : XLogSegNo targetSeg; /* segid of targetLSN */
8001 : : XLogSegNo oldestSeg; /* actual oldest segid */
8002 : : XLogSegNo oldestSegMaxWalSize; /* oldest segid kept by max_wal_size */
8003 : : XLogSegNo oldestSlotSeg; /* oldest segid kept by slot */
8004 : : uint64 keepSegs;
8005 : :
8006 : : /*
8007 : : * slot does not reserve WAL. Either deactivated, or has never been active
8008 : : */
129 alvherre@kurilemu.de 8009 [ + + ]:GNC 618 : if (!XLogRecPtrIsValid(targetLSN))
2168 alvherre@alvh.no-ip. 8010 :CBC 27 : return WALAVAIL_INVALID_LSN;
8011 : :
8012 : : /*
8013 : : * Calculate the oldest segment currently reserved by all slots,
8014 : : * considering wal_keep_size and max_slot_wal_keep_size. Initialize
8015 : : * oldestSlotSeg to the current segment.
8016 : : */
2071 8017 : 591 : currpos = GetXLogWriteRecPtr();
8018 : 591 : XLByteToSeg(currpos, oldestSlotSeg, wal_segment_size);
2168 8019 : 591 : KeepLogSeg(currpos, &oldestSlotSeg);
8020 : :
8021 : : /*
8022 : : * Find the oldest extant segment file. We get 1 until checkpoint removes
8023 : : * the first WAL segment file since startup, which causes the status being
8024 : : * wrong under certain abnormal conditions but that doesn't actually harm.
8025 : : */
8026 : 591 : oldestSeg = XLogGetLastRemovedSegno() + 1;
8027 : :
8028 : : /* calculate oldest segment by max_wal_size */
8029 : 591 : XLByteToSeg(currpos, currSeg, wal_segment_size);
2090 8030 : 591 : keepSegs = ConvertToXSegs(max_wal_size_mb, wal_segment_size) + 1;
8031 : :
2168 8032 [ + + ]: 591 : if (currSeg > keepSegs)
8033 : 8 : oldestSegMaxWalSize = currSeg - keepSegs;
8034 : : else
8035 : 583 : oldestSegMaxWalSize = 1;
8036 : :
8037 : : /* the segment we care about */
2071 8038 : 591 : XLByteToSeg(targetLSN, targetSeg, wal_segment_size);
8039 : :
8040 : : /*
8041 : : * No point in returning reserved or extended status values if the
8042 : : * targetSeg is known to be lost.
8043 : : */
2090 8044 [ + + ]: 591 : if (targetSeg >= oldestSlotSeg)
8045 : : {
8046 : : /* show "reserved" when targetSeg is within max_wal_size */
8047 [ + + ]: 590 : if (targetSeg >= oldestSegMaxWalSize)
2168 8048 : 588 : return WALAVAIL_RESERVED;
8049 : :
8050 : : /* being retained by slots exceeding max_wal_size */
2090 8051 : 2 : return WALAVAIL_EXTENDED;
8052 : : }
8053 : :
8054 : : /* WAL segments are no longer retained but haven't been removed yet */
8055 [ + - ]: 1 : if (targetSeg >= oldestSeg)
8056 : 1 : return WALAVAIL_UNRESERVED;
8057 : :
8058 : : /* Definitely lost */
2168 alvherre@alvh.no-ip. 8059 :UBC 0 : return WALAVAIL_REMOVED;
8060 : : }
8061 : :
8062 : :
8063 : : /*
8064 : : * Retreat *logSegNo to the last segment that we need to retain because of
8065 : : * either wal_keep_size or replication slots.
8066 : : *
8067 : : * This is calculated by subtracting wal_keep_size from the given xlog
8068 : : * location, recptr and by making sure that that result is below the
8069 : : * requirement of replication slots. For the latter criterion we do consider
8070 : : * the effects of max_slot_wal_keep_size: reserve at most that much space back
8071 : : * from recptr.
8072 : : *
8073 : : * Note about replication slots: if this function calculates a value
8074 : : * that's further ahead than what slots need reserved, then affected
8075 : : * slots need to be invalidated and this function invoked again.
8076 : : * XXX it might be a good idea to rewrite this function so that
8077 : : * invalidation is optionally done here, instead.
8078 : : */
8079 : : static void
5012 heikki.linnakangas@i 8080 :CBC 2398 : KeepLogSeg(XLogRecPtr recptr, XLogSegNo *logSegNo)
8081 : : {
8082 : : XLogSegNo currSegNo;
8083 : : XLogSegNo segno;
8084 : : XLogRecPtr keep;
8085 : :
2168 alvherre@alvh.no-ip. 8086 : 2398 : XLByteToSeg(recptr, currSegNo, wal_segment_size);
8087 : 2398 : segno = currSegNo;
8088 : :
8089 : : /* Calculate how many segments are kept by slots. */
8090 : 2398 : keep = XLogGetReplicationSlotMinimumLSN();
129 alvherre@kurilemu.de 8091 [ + + + + ]:GNC 2398 : if (XLogRecPtrIsValid(keep) && keep < recptr)
8092 : : {
2168 alvherre@alvh.no-ip. 8093 :CBC 747 : XLByteToSeg(keep, segno, wal_segment_size);
8094 : :
8095 : : /*
8096 : : * Account for max_slot_wal_keep_size to avoid keeping more than
8097 : : * configured. However, don't do that during a binary upgrade: if
8098 : : * slots were to be invalidated because of this, it would not be
8099 : : * possible to preserve logical ones during the upgrade.
8100 : : */
247 akapila@postgresql.o 8101 [ + + + - ]: 747 : if (max_slot_wal_keep_size_mb >= 0 && !IsBinaryUpgrade)
8102 : : {
8103 : : uint64 slot_keep_segs;
8104 : :
2168 alvherre@alvh.no-ip. 8105 : 23 : slot_keep_segs =
8106 : 23 : ConvertToXSegs(max_slot_wal_keep_size_mb, wal_segment_size);
8107 : :
8108 [ + + ]: 23 : if (currSegNo - segno > slot_keep_segs)
8109 : 6 : segno = currSegNo - slot_keep_segs;
8110 : : }
8111 : : }
8112 : :
8113 : : /*
8114 : : * If WAL summarization is in use, don't remove WAL that has yet to be
8115 : : * summarized.
8116 : : */
628 rhaas@postgresql.org 8117 : 2398 : keep = GetOldestUnsummarizedLSN(NULL, NULL);
129 alvherre@kurilemu.de 8118 [ + + ]:GNC 2398 : if (XLogRecPtrIsValid(keep))
8119 : : {
8120 : : XLogSegNo unsummarized_segno;
8121 : :
816 rhaas@postgresql.org 8122 :CBC 7 : XLByteToSeg(keep, unsummarized_segno, wal_segment_size);
8123 [ + - ]: 7 : if (unsummarized_segno < segno)
8124 : 7 : segno = unsummarized_segno;
8125 : : }
8126 : :
8127 : : /* but, keep at least wal_keep_size if that's set */
2064 fujii@postgresql.org 8128 [ + + ]: 2398 : if (wal_keep_size_mb > 0)
8129 : : {
8130 : : uint64 keep_segs;
8131 : :
8132 : 74 : keep_segs = ConvertToXSegs(wal_keep_size_mb, wal_segment_size);
8133 [ + - ]: 74 : if (currSegNo - segno < keep_segs)
8134 : : {
8135 : : /* avoid underflow, don't go below 1 */
8136 [ + + ]: 74 : if (currSegNo <= keep_segs)
8137 : 70 : segno = 1;
8138 : : else
8139 : 4 : segno = currSegNo - keep_segs;
8140 : : }
8141 : : }
8142 : :
8143 : : /* don't delete WAL segments newer than the calculated segment */
2071 alvherre@alvh.no-ip. 8144 [ + + ]: 2398 : if (segno < *logSegNo)
5012 heikki.linnakangas@i 8145 : 355 : *logSegNo = segno;
5353 simon@2ndQuadrant.co 8146 : 2398 : }
8147 : :
8148 : : /*
8149 : : * Write a NEXTOID log record
8150 : : */
8151 : : void
9263 vadim4o@yahoo.com 8152 : 638 : XLogPutNextOid(Oid nextOid)
8153 : : {
4133 heikki.linnakangas@i 8154 : 638 : XLogBeginInsert();
397 peter@eisentraut.org 8155 : 638 : XLogRegisterData(&nextOid, sizeof(Oid));
4133 heikki.linnakangas@i 8156 : 638 : (void) XLogInsert(RM_XLOG_ID, XLOG_NEXTOID);
8157 : :
8158 : : /*
8159 : : * We need not flush the NEXTOID record immediately, because any of the
8160 : : * just-allocated OIDs could only reach disk as part of a tuple insert or
8161 : : * update that would have its own XLOG record that must follow the NEXTOID
8162 : : * record. Therefore, the standard buffer LSN interlock applied to those
8163 : : * records will ensure no such OID reaches disk before the NEXTOID record
8164 : : * does.
8165 : : *
8166 : : * Note, however, that the above statement only covers state "within" the
8167 : : * database. When we use a generated OID as a file or directory name, we
8168 : : * are in a sense violating the basic WAL rule, because that filesystem
8169 : : * change may reach disk before the NEXTOID WAL record does. The impact
8170 : : * of this is that if a database crash occurs immediately afterward, we
8171 : : * might after restart re-generate the same OID and find that it conflicts
8172 : : * with the leftover file or directory. But since for safety's sake we
8173 : : * always loop until finding a nonconflicting filename, this poses no real
8174 : : * problem in practice. See pgsql-hackers discussion 27-Sep-2006.
8175 : : */
7626 tgl@sss.pgh.pa.us 8176 : 638 : }
8177 : :
8178 : : /*
8179 : : * Write an XLOG SWITCH record.
8180 : : *
8181 : : * Here we just blindly issue an XLogInsert request for the record.
8182 : : * All the magic happens inside XLogInsert.
8183 : : *
8184 : : * The return value is either the end+1 address of the switch record,
8185 : : * or the end+1 address of the prior segment if we did not need to
8186 : : * write a switch record because we are already at segment start.
8187 : : */
8188 : : XLogRecPtr
3370 andres@anarazel.de 8189 : 816 : RequestXLogSwitch(bool mark_unimportant)
8190 : : {
8191 : : XLogRecPtr RecPtr;
8192 : :
8193 : : /* XLOG SWITCH has no data */
4133 heikki.linnakangas@i 8194 : 816 : XLogBeginInsert();
8195 : :
3370 andres@anarazel.de 8196 [ - + ]: 816 : if (mark_unimportant)
3370 andres@anarazel.de 8197 :UBC 0 : XLogSetRecordFlags(XLOG_MARK_UNIMPORTANT);
4133 heikki.linnakangas@i 8198 :CBC 816 : RecPtr = XLogInsert(RM_XLOG_ID, XLOG_SWITCH);
8199 : :
7161 tgl@sss.pgh.pa.us 8200 : 816 : return RecPtr;
8201 : : }
8202 : :
8203 : : /*
8204 : : * Write a RESTORE POINT record
8205 : : */
8206 : : XLogRecPtr
5514 simon@2ndQuadrant.co 8207 : 3 : XLogRestorePoint(const char *rpName)
8208 : : {
8209 : : XLogRecPtr RecPtr;
8210 : : xl_restore_point xlrec;
8211 : :
8212 : 3 : xlrec.rp_time = GetCurrentTimestamp();
4409 tgl@sss.pgh.pa.us 8213 : 3 : strlcpy(xlrec.rp_name, rpName, MAXFNAMELEN);
8214 : :
4133 heikki.linnakangas@i 8215 : 3 : XLogBeginInsert();
397 peter@eisentraut.org 8216 : 3 : XLogRegisterData(&xlrec, sizeof(xl_restore_point));
8217 : :
4133 heikki.linnakangas@i 8218 : 3 : RecPtr = XLogInsert(RM_XLOG_ID, XLOG_RESTORE_POINT);
8219 : :
5498 rhaas@postgresql.org 8220 [ + - ]: 3 : ereport(LOG,
8221 : : errmsg("restore point \"%s\" created at %X/%08X",
8222 : : rpName, LSN_FORMAT_ARGS(RecPtr)));
8223 : :
5514 simon@2ndQuadrant.co 8224 : 3 : return RecPtr;
8225 : : }
8226 : :
8227 : : /*
8228 : : * Write an empty XLOG record to assign a distinct LSN.
8229 : : *
8230 : : * This is used by some index AMs when building indexes on permanent relations
8231 : : * with wal_level=minimal. In that scenario, WAL-logging will start after
8232 : : * commit, but the index AM needs distinct LSNs to detect concurrent page
8233 : : * modifications. When the current WAL insert position hasn't advanced since
8234 : : * the last call, we emit a dummy record to ensure we get a new, distinct LSN.
8235 : : */
8236 : : XLogRecPtr
2 pg@bowt.ie 8237 :GNC 313 : XLogAssignLSN(void)
8238 : : {
8239 : 313 : int dummy = 0;
8240 : :
8241 : : /*
8242 : : * Records other than XLOG_SWITCH must have content. We use an integer 0
8243 : : * to satisfy this restriction.
8244 : : */
8245 : 313 : XLogBeginInsert();
8246 : 313 : XLogSetRecordFlags(XLOG_MARK_UNIMPORTANT);
8247 : 313 : XLogRegisterData(&dummy, sizeof(dummy));
8248 : 313 : return XLogInsert(RM_XLOG_ID, XLOG_ASSIGN_LSN);
8249 : : }
8250 : :
8251 : : /*
8252 : : * Check if any of the GUC parameters that are critical for hot standby
8253 : : * have changed, and update the value in pg_control file if necessary.
8254 : : */
8255 : : static void
5800 heikki.linnakangas@i 8256 :CBC 939 : XLogReportParameters(void)
8257 : : {
8258 [ + + ]: 939 : if (wal_level != ControlFile->wal_level ||
4456 rhaas@postgresql.org 8259 [ + + ]: 684 : wal_log_hints != ControlFile->wal_log_hints ||
5800 heikki.linnakangas@i 8260 [ + + ]: 597 : MaxConnections != ControlFile->MaxConnections ||
4637 rhaas@postgresql.org 8261 [ + + ]: 596 : max_worker_processes != ControlFile->max_worker_processes ||
2588 michael@paquier.xyz 8262 [ + + ]: 593 : max_wal_senders != ControlFile->max_wal_senders ||
5800 heikki.linnakangas@i 8263 [ + + ]: 568 : max_prepared_xacts != ControlFile->max_prepared_xacts ||
4120 alvherre@alvh.no-ip. 8264 [ + - ]: 467 : max_locks_per_xact != ControlFile->max_locks_per_xact ||
8265 [ + + ]: 467 : track_commit_timestamp != ControlFile->track_commit_timestamp)
8266 : : {
8267 : : /*
8268 : : * The change in number of backend slots doesn't need to be WAL-logged
8269 : : * if archiving is not enabled, as you can't start archive recovery
8270 : : * with wal_level=minimal anyway. We don't really care about the
8271 : : * values in pg_control either if wal_level=minimal, but seems better
8272 : : * to keep them up-to-date to avoid confusion.
8273 : : */
5800 heikki.linnakangas@i 8274 [ + + + + ]: 484 : if (wal_level != ControlFile->wal_level || XLogIsNeeded())
8275 : : {
8276 : : xl_parameter_change xlrec;
8277 : : XLogRecPtr recptr;
8278 : :
8279 : 459 : xlrec.MaxConnections = MaxConnections;
4637 rhaas@postgresql.org 8280 : 459 : xlrec.max_worker_processes = max_worker_processes;
2588 michael@paquier.xyz 8281 : 459 : xlrec.max_wal_senders = max_wal_senders;
5800 heikki.linnakangas@i 8282 : 459 : xlrec.max_prepared_xacts = max_prepared_xacts;
8283 : 459 : xlrec.max_locks_per_xact = max_locks_per_xact;
8284 : 459 : xlrec.wal_level = wal_level;
4456 rhaas@postgresql.org 8285 : 459 : xlrec.wal_log_hints = wal_log_hints;
4120 alvherre@alvh.no-ip. 8286 : 459 : xlrec.track_commit_timestamp = track_commit_timestamp;
8287 : :
4133 heikki.linnakangas@i 8288 : 459 : XLogBeginInsert();
397 peter@eisentraut.org 8289 : 459 : XLogRegisterData(&xlrec, sizeof(xlrec));
8290 : :
4133 heikki.linnakangas@i 8291 : 459 : recptr = XLogInsert(RM_XLOG_ID, XLOG_PARAMETER_CHANGE);
4372 fujii@postgresql.org 8292 : 459 : XLogFlush(recptr);
8293 : : }
8294 : :
2106 tmunro@postgresql.or 8295 : 484 : LWLockAcquire(ControlFileLock, LW_EXCLUSIVE);
8296 : :
5800 heikki.linnakangas@i 8297 : 484 : ControlFile->MaxConnections = MaxConnections;
4637 rhaas@postgresql.org 8298 : 484 : ControlFile->max_worker_processes = max_worker_processes;
2588 michael@paquier.xyz 8299 : 484 : ControlFile->max_wal_senders = max_wal_senders;
5800 heikki.linnakangas@i 8300 : 484 : ControlFile->max_prepared_xacts = max_prepared_xacts;
8301 : 484 : ControlFile->max_locks_per_xact = max_locks_per_xact;
8302 : 484 : ControlFile->wal_level = wal_level;
4456 rhaas@postgresql.org 8303 : 484 : ControlFile->wal_log_hints = wal_log_hints;
4120 alvherre@alvh.no-ip. 8304 : 484 : ControlFile->track_commit_timestamp = track_commit_timestamp;
5800 heikki.linnakangas@i 8305 : 484 : UpdateControlFile();
8306 : :
2106 tmunro@postgresql.or 8307 : 484 : LWLockRelease(ControlFileLock);
8308 : : }
5898 heikki.linnakangas@i 8309 : 939 : }
8310 : :
8311 : : /*
8312 : : * Update full_page_writes in shared memory, and write an
8313 : : * XLOG_FPW_CHANGE record if necessary.
8314 : : *
8315 : : * Note: this function assumes there is no other process running
8316 : : * concurrently that could update it.
8317 : : */
8318 : : void
5163 simon@2ndQuadrant.co 8319 : 1593 : UpdateFullPageWrites(void)
8320 : : {
8321 : 1593 : XLogCtlInsert *Insert = &XLogCtl->Insert;
8322 : : bool recoveryInProgress;
8323 : :
8324 : : /*
8325 : : * Do nothing if full_page_writes has not been changed.
8326 : : *
8327 : : * It's safe to check the shared full_page_writes without the lock,
8328 : : * because we assume that there is no concurrently running process which
8329 : : * can update it.
8330 : : */
8331 [ + + ]: 1593 : if (fullPageWrites == Insert->fullPageWrites)
8332 : 1079 : return;
8333 : :
8334 : : /*
8335 : : * Perform this outside critical section so that the WAL insert
8336 : : * initialization done by RecoveryInProgress() doesn't trigger an
8337 : : * assertion failure.
8338 : : */
2725 akapila@postgresql.o 8339 : 514 : recoveryInProgress = RecoveryInProgress();
8340 : :
5122 heikki.linnakangas@i 8341 : 514 : START_CRIT_SECTION();
8342 : :
8343 : : /*
8344 : : * It's always safe to take full page images, even when not strictly
8345 : : * required, but not the other round. So if we're setting full_page_writes
8346 : : * to true, first set it true and then write the WAL record. If we're
8347 : : * setting it to false, first write the WAL record and then set the global
8348 : : * flag.
8349 : : */
8350 [ + + ]: 514 : if (fullPageWrites)
8351 : : {
4377 8352 : 503 : WALInsertLockAcquireExclusive();
5122 8353 : 503 : Insert->fullPageWrites = true;
4377 8354 : 503 : WALInsertLockRelease();
8355 : : }
8356 : :
8357 : : /*
8358 : : * Write an XLOG_FPW_CHANGE record. This allows us to keep track of
8359 : : * full_page_writes during archive recovery, if required.
8360 : : */
2725 akapila@postgresql.o 8361 [ + + - + ]: 514 : if (XLogStandbyInfoActive() && !recoveryInProgress)
8362 : : {
4133 heikki.linnakangas@i 8363 :UBC 0 : XLogBeginInsert();
397 peter@eisentraut.org 8364 : 0 : XLogRegisterData(&fullPageWrites, sizeof(bool));
8365 : :
4133 heikki.linnakangas@i 8366 : 0 : XLogInsert(RM_XLOG_ID, XLOG_FPW_CHANGE);
8367 : : }
8368 : :
5122 heikki.linnakangas@i 8369 [ + + ]:CBC 514 : if (!fullPageWrites)
8370 : : {
4377 8371 : 11 : WALInsertLockAcquireExclusive();
5122 8372 : 11 : Insert->fullPageWrites = false;
4377 8373 : 11 : WALInsertLockRelease();
8374 : : }
5122 8375 [ - + ]: 514 : END_CRIT_SECTION();
8376 : : }
8377 : :
8378 : : /*
8379 : : * XLOG resource manager's routines
8380 : : *
8381 : : * Definitions of info values are in include/catalog/pg_control.h, though
8382 : : * not all record types are related to control file updates.
8383 : : *
8384 : : * NOTE: Some XLOG record types that are directly related to WAL recovery
8385 : : * are handled in xlogrecovery_redo().
8386 : : */
8387 : : void
4133 8388 : 107715 : xlog_redo(XLogReaderState *record)
8389 : : {
8390 : 107715 : uint8 info = XLogRecGetInfo(record) & ~XLR_INFO_MASK;
8391 : 107715 : XLogRecPtr lsn = record->EndRecPtr;
8392 : :
8393 : : /*
8394 : : * In XLOG rmgr, backup blocks are only used by XLOG_FPI and
8395 : : * XLOG_FPI_FOR_HINT records.
8396 : : */
4129 8397 [ + + + + : 107715 : Assert(info == XLOG_FPI || info == XLOG_FPI_FOR_HINT ||
- + ]
8398 : : !XLogRecHasAnyBlockRefs(record));
8399 : :
9128 tgl@sss.pgh.pa.us 8400 [ + + ]: 107715 : if (info == XLOG_NEXTOID)
8401 : : {
8402 : : Oid nextOid;
8403 : :
8404 : : /*
8405 : : * We used to try to take the maximum of TransamVariables->nextOid and
8406 : : * the recorded nextOid, but that fails if the OID counter wraps
8407 : : * around. Since no OID allocation should be happening during replay
8408 : : * anyway, better to just believe the record exactly. We still take
8409 : : * OidGenLock while setting the variable, just in case.
8410 : : */
9263 vadim4o@yahoo.com 8411 : 96 : memcpy(&nextOid, XLogRecGetData(record), sizeof(Oid));
5151 tgl@sss.pgh.pa.us 8412 : 96 : LWLockAcquire(OidGenLock, LW_EXCLUSIVE);
828 heikki.linnakangas@i 8413 : 96 : TransamVariables->nextOid = nextOid;
8414 : 96 : TransamVariables->oidCount = 0;
5151 tgl@sss.pgh.pa.us 8415 : 96 : LWLockRelease(OidGenLock);
8416 : : }
9133 8417 [ + + ]: 107619 : else if (info == XLOG_CHECKPOINT_SHUTDOWN)
8418 : : {
8419 : : CheckPoint checkPoint;
8420 : : TimeLineID replayTLI;
8421 : :
8422 : 42 : memcpy(&checkPoint, XLogRecGetData(record), sizeof(CheckPoint));
8423 : : /* In a SHUTDOWN checkpoint, believe the counters exactly */
5151 8424 : 42 : LWLockAcquire(XidGenLock, LW_EXCLUSIVE);
828 heikki.linnakangas@i 8425 : 42 : TransamVariables->nextXid = checkPoint.nextXid;
5151 tgl@sss.pgh.pa.us 8426 : 42 : LWLockRelease(XidGenLock);
8427 : 42 : LWLockAcquire(OidGenLock, LW_EXCLUSIVE);
828 heikki.linnakangas@i 8428 : 42 : TransamVariables->nextOid = checkPoint.nextOid;
8429 : 42 : TransamVariables->oidCount = 0;
5151 tgl@sss.pgh.pa.us 8430 : 42 : LWLockRelease(OidGenLock);
7585 8431 : 42 : MultiXactSetNextMXact(checkPoint.nextMulti,
8432 : : checkPoint.nextMultiOffset);
8433 : :
3823 andres@anarazel.de 8434 : 42 : MultiXactAdvanceOldest(checkPoint.oldestMulti,
8435 : : checkPoint.oldestMultiDB);
8436 : :
8437 : : /*
8438 : : * No need to set oldestClogXid here as well; it'll be set when we
8439 : : * redo an xl_clog_truncate if it changed since initialization.
8440 : : */
5870 tgl@sss.pgh.pa.us 8441 : 42 : SetTransactionIdLimit(checkPoint.oldestXid, checkPoint.oldestXidDB);
8442 : :
8443 : : /*
8444 : : * If we see a shutdown checkpoint while waiting for an end-of-backup
8445 : : * record, the backup was canceled and the end-of-backup record will
8446 : : * never arrive.
8447 : : */
4769 heikki.linnakangas@i 8448 [ + + ]: 42 : if (ArchiveRecoveryRequested &&
129 alvherre@kurilemu.de 8449 [ - + ]:GNC 41 : XLogRecPtrIsValid(ControlFile->backupStartPoint) &&
129 alvherre@kurilemu.de 8450 [ # # ]:UNC 0 : !XLogRecPtrIsValid(ControlFile->backupEndPoint))
5151 tgl@sss.pgh.pa.us 8451 [ # # ]:UBC 0 : ereport(PANIC,
8452 : : (errmsg("online backup was canceled, recovery cannot continue")));
8453 : :
8454 : : /*
8455 : : * If we see a shutdown checkpoint, we know that nothing was running
8456 : : * on the primary at this point. So fake-up an empty running-xacts
8457 : : * record and use that here and now. Recover additional standby state
8458 : : * for prepared transactions.
8459 : : */
5930 simon@2ndQuadrant.co 8460 [ + + ]:CBC 42 : if (standbyState >= STANDBY_INITIALIZED)
8461 : : {
8462 : : TransactionId *xids;
8463 : : int nxids;
8464 : : TransactionId oldestActiveXID;
8465 : : TransactionId latestCompletedXid;
8466 : : RunningTransactionsData running;
8467 : :
5815 heikki.linnakangas@i 8468 : 39 : oldestActiveXID = PrescanPreparedTransactions(&xids, &nxids);
8469 : :
8470 : : /* Update pg_subtrans entries for any prepared transactions */
626 8471 : 39 : StandbyRecoverPreparedTransactions();
8472 : :
8473 : : /*
8474 : : * Construct a RunningTransactions snapshot representing a shut
8475 : : * down server, with only prepared transactions still alive. We're
8476 : : * never overflowed at this point because all subxids are listed
8477 : : * with their parent prepared transactions.
8478 : : */
5815 8479 : 39 : running.xcnt = nxids;
4851 simon@2ndQuadrant.co 8480 : 39 : running.subxcnt = 0;
626 heikki.linnakangas@i 8481 : 39 : running.subxid_status = SUBXIDS_IN_SUBTRANS;
2042 andres@anarazel.de 8482 : 39 : running.nextXid = XidFromFullTransactionId(checkPoint.nextXid);
5815 heikki.linnakangas@i 8483 : 39 : running.oldestRunningXid = oldestActiveXID;
2042 andres@anarazel.de 8484 : 39 : latestCompletedXid = XidFromFullTransactionId(checkPoint.nextXid);
5785 simon@2ndQuadrant.co 8485 [ - + ]: 39 : TransactionIdRetreat(latestCompletedXid);
5784 8486 [ - + ]: 39 : Assert(TransactionIdIsNormal(latestCompletedXid));
5785 8487 : 39 : running.latestCompletedXid = latestCompletedXid;
5815 heikki.linnakangas@i 8488 : 39 : running.xids = xids;
8489 : :
8490 : 39 : ProcArrayApplyRecoveryInfo(&running);
8491 : : }
8492 : :
8493 : : /* ControlFile->checkPointCopy always tracks the latest ckpt XID */
2106 tmunro@postgresql.or 8494 : 42 : LWLockAcquire(ControlFileLock, LW_EXCLUSIVE);
2042 andres@anarazel.de 8495 : 42 : ControlFile->checkPointCopy.nextXid = checkPoint.nextXid;
2106 tmunro@postgresql.or 8496 : 42 : LWLockRelease(ControlFileLock);
8497 : :
8498 : : /*
8499 : : * We should've already switched to the new TLI before replaying this
8500 : : * record.
8501 : : */
1488 heikki.linnakangas@i 8502 : 42 : (void) GetCurrentReplayRecPtr(&replayTLI);
1591 rhaas@postgresql.org 8503 [ - + ]: 42 : if (checkPoint.ThisTimeLineID != replayTLI)
4846 heikki.linnakangas@i 8504 [ # # ]:UBC 0 : ereport(PANIC,
8505 : : (errmsg("unexpected timeline ID %u (should be %u) in shutdown checkpoint record",
8506 : : checkPoint.ThisTimeLineID, replayTLI)));
8507 : :
1572 rhaas@postgresql.org 8508 :CBC 42 : RecoveryRestartPoint(&checkPoint, record);
8509 : :
8510 : : /*
8511 : : * After replaying a checkpoint record, free all smgr objects.
8512 : : * Otherwise we would never do so for dropped relations, as the
8513 : : * startup does not process shared invalidation messages or call
8514 : : * AtEOXact_SMgr().
8515 : : */
186 michael@paquier.xyz 8516 : 42 : smgrdestroyall();
8517 : : }
9133 tgl@sss.pgh.pa.us 8518 [ + + ]: 107577 : else if (info == XLOG_CHECKPOINT_ONLINE)
8519 : : {
8520 : : CheckPoint checkPoint;
8521 : : TimeLineID replayTLI;
8522 : :
8523 : 692 : memcpy(&checkPoint, XLogRecGetData(record), sizeof(CheckPoint));
8524 : : /* In an ONLINE checkpoint, treat the XID counter as a minimum */
5151 8525 : 692 : LWLockAcquire(XidGenLock, LW_EXCLUSIVE);
828 heikki.linnakangas@i 8526 [ - + ]: 692 : if (FullTransactionIdPrecedes(TransamVariables->nextXid,
8527 : : checkPoint.nextXid))
828 heikki.linnakangas@i 8528 :UBC 0 : TransamVariables->nextXid = checkPoint.nextXid;
5151 tgl@sss.pgh.pa.us 8529 :CBC 692 : LWLockRelease(XidGenLock);
8530 : :
8531 : : /*
8532 : : * We ignore the nextOid counter in an ONLINE checkpoint, preferring
8533 : : * to track OID assignment through XLOG_NEXTOID records. The nextOid
8534 : : * counter is from the start of the checkpoint and might well be stale
8535 : : * compared to later XLOG_NEXTOID records. We could try to take the
8536 : : * maximum of the nextOid counter and our latest value, but since
8537 : : * there's no particular guarantee about the speed with which the OID
8538 : : * counter wraps around, that's a risky thing to do. In any case,
8539 : : * users of the nextOid counter are required to avoid assignment of
8540 : : * duplicates, so that a somewhat out-of-date value should be safe.
8541 : : */
8542 : :
8543 : : /* Handle multixact */
7585 8544 : 692 : MultiXactAdvanceNextMXact(checkPoint.nextMulti,
8545 : : checkPoint.nextMultiOffset);
8546 : :
8547 : : /*
8548 : : * NB: This may perform multixact truncation when replaying WAL
8549 : : * generated by an older primary.
8550 : : */
3823 andres@anarazel.de 8551 : 692 : MultiXactAdvanceOldest(checkPoint.oldestMulti,
8552 : : checkPoint.oldestMultiDB);
828 heikki.linnakangas@i 8553 [ - + ]: 692 : if (TransactionIdPrecedes(TransamVariables->oldestXid,
8554 : : checkPoint.oldestXid))
5870 tgl@sss.pgh.pa.us 8555 :UBC 0 : SetTransactionIdLimit(checkPoint.oldestXid,
8556 : : checkPoint.oldestXidDB);
8557 : : /* ControlFile->checkPointCopy always tracks the latest ckpt XID */
2106 tmunro@postgresql.or 8558 :CBC 692 : LWLockAcquire(ControlFileLock, LW_EXCLUSIVE);
2042 andres@anarazel.de 8559 : 692 : ControlFile->checkPointCopy.nextXid = checkPoint.nextXid;
2106 tmunro@postgresql.or 8560 : 692 : LWLockRelease(ControlFileLock);
8561 : :
8562 : : /* TLI should not change in an on-line checkpoint */
1488 heikki.linnakangas@i 8563 : 692 : (void) GetCurrentReplayRecPtr(&replayTLI);
1591 rhaas@postgresql.org 8564 [ - + ]: 692 : if (checkPoint.ThisTimeLineID != replayTLI)
8068 tgl@sss.pgh.pa.us 8565 [ # # ]:UBC 0 : ereport(PANIC,
8566 : : (errmsg("unexpected timeline ID %u (should be %u) in online checkpoint record",
8567 : : checkPoint.ThisTimeLineID, replayTLI)));
8568 : :
1572 rhaas@postgresql.org 8569 :CBC 692 : RecoveryRestartPoint(&checkPoint, record);
8570 : :
8571 : : /*
8572 : : * After replaying a checkpoint record, free all smgr objects.
8573 : : * Otherwise we would never do so for dropped relations, as the
8574 : : * startup does not process shared invalidation messages or call
8575 : : * AtEOXact_SMgr().
8576 : : */
186 michael@paquier.xyz 8577 : 692 : smgrdestroyall();
8578 : : }
1628 alvherre@alvh.no-ip. 8579 [ + + ]: 106885 : else if (info == XLOG_OVERWRITE_CONTRECORD)
8580 : : {
8581 : : /* nothing to do here, handled in xlogrecovery_redo() */
8582 : : }
4793 simon@2ndQuadrant.co 8583 [ + + ]: 106884 : else if (info == XLOG_END_OF_RECOVERY)
8584 : : {
8585 : : xl_end_of_recovery xlrec;
8586 : : TimeLineID replayTLI;
8587 : :
8588 : 11 : memcpy(&xlrec, XLogRecGetData(record), sizeof(xl_end_of_recovery));
8589 : :
8590 : : /*
8591 : : * For Hot Standby, we could treat this like a Shutdown Checkpoint,
8592 : : * but this case is rarer and harder to test, so the benefit doesn't
8593 : : * outweigh the potential extra cost of maintenance.
8594 : : */
8595 : :
8596 : : /*
8597 : : * We should've already switched to the new TLI before replaying this
8598 : : * record.
8599 : : */
1488 heikki.linnakangas@i 8600 : 11 : (void) GetCurrentReplayRecPtr(&replayTLI);
1591 rhaas@postgresql.org 8601 [ - + ]: 11 : if (xlrec.ThisTimeLineID != replayTLI)
4793 simon@2ndQuadrant.co 8602 [ # # ]:UBC 0 : ereport(PANIC,
8603 : : (errmsg("unexpected timeline ID %u (should be %u) in end-of-recovery record",
8604 : : xlrec.ThisTimeLineID, replayTLI)));
8605 : : }
6874 tgl@sss.pgh.pa.us 8606 [ + - ]:CBC 106873 : else if (info == XLOG_NOOP)
8607 : : {
8608 : : /* nothing to do here */
8609 : : }
7161 8610 [ + + ]: 106873 : else if (info == XLOG_SWITCH)
8611 : : {
8612 : : /* nothing to do here */
8613 : : }
5514 simon@2ndQuadrant.co 8614 [ + + ]: 106418 : else if (info == XLOG_RESTORE_POINT)
8615 : : {
8616 : : /* nothing to do here, handled in xlogrecovery.c */
8617 : : }
2 pg@bowt.ie 8618 [ + + ]:GNC 106413 : else if (info == XLOG_ASSIGN_LSN)
8619 : : {
8620 : : /* nothing to do here, see XLogGetFakeLSN() */
8621 : : }
4129 heikki.linnakangas@i 8622 [ + + + + ]:CBC 44086 : else if (info == XLOG_FPI || info == XLOG_FPI_FOR_HINT)
8623 : : {
8624 : : /*
8625 : : * XLOG_FPI records contain nothing else but one or more block
8626 : : * references. Every block reference must include a full-page image
8627 : : * even if full_page_writes was disabled when the record was generated
8628 : : * - otherwise there would be no point in this record.
8629 : : *
8630 : : * XLOG_FPI_FOR_HINT records are generated when a page needs to be
8631 : : * WAL-logged because of a hint bit update. They are only generated
8632 : : * when checksums and/or wal_log_hints are enabled. They may include
8633 : : * no full-page images if full_page_writes was disabled when they were
8634 : : * generated. In this case there is nothing to do here.
8635 : : *
8636 : : * No recovery conflicts are generated by these generic records - if a
8637 : : * resource manager needs to generate conflicts, it has to define a
8638 : : * separate WAL record type and redo routine.
8639 : : */
1458 tmunro@postgresql.or 8640 [ + + ]: 91357 : for (uint8 block_id = 0; block_id <= XLogRecMaxBlockId(record); block_id++)
8641 : : {
8642 : : Buffer buffer;
8643 : :
1698 fujii@postgresql.org 8644 [ + + ]: 48115 : if (!XLogRecHasBlockImage(record, block_id))
8645 : : {
8646 [ - + ]: 68 : if (info == XLOG_FPI)
1698 fujii@postgresql.org 8647 [ # # ]:UBC 0 : elog(ERROR, "XLOG_FPI record did not contain a full-page image");
1698 fujii@postgresql.org 8648 :CBC 68 : continue;
8649 : : }
8650 : :
2538 heikki.linnakangas@i 8651 [ - + ]: 48047 : if (XLogReadBufferForRedo(record, block_id, &buffer) != BLK_RESTORED)
2538 heikki.linnakangas@i 8652 [ # # ]:UBC 0 : elog(ERROR, "unexpected XLogReadBufferForRedo result when restoring backup block");
2538 heikki.linnakangas@i 8653 :CBC 48047 : UnlockReleaseBuffer(buffer);
8654 : : }
8655 : : }
5914 8656 [ + + ]: 844 : else if (info == XLOG_BACKUP_END)
8657 : : {
8658 : : /* nothing to do here, handled in xlogrecovery_redo() */
8659 : : }
5800 8660 [ + + ]: 749 : else if (info == XLOG_PARAMETER_CHANGE)
8661 : : {
8662 : : xl_parameter_change xlrec;
8663 : :
8664 : : /* Update our copy of the parameters in pg_control */
8665 : 38 : memcpy(&xlrec, XLogRecGetData(record), sizeof(xl_parameter_change));
8666 : :
5795 8667 : 38 : LWLockAcquire(ControlFileLock, LW_EXCLUSIVE);
5800 8668 : 38 : ControlFile->MaxConnections = xlrec.MaxConnections;
4637 rhaas@postgresql.org 8669 : 38 : ControlFile->max_worker_processes = xlrec.max_worker_processes;
2588 michael@paquier.xyz 8670 : 38 : ControlFile->max_wal_senders = xlrec.max_wal_senders;
5800 heikki.linnakangas@i 8671 : 38 : ControlFile->max_prepared_xacts = xlrec.max_prepared_xacts;
8672 : 38 : ControlFile->max_locks_per_xact = xlrec.max_locks_per_xact;
8673 : 38 : ControlFile->wal_level = xlrec.wal_level;
4077 8674 : 38 : ControlFile->wal_log_hints = xlrec.wal_log_hints;
8675 : :
8676 : : /*
8677 : : * Update minRecoveryPoint to ensure that if recovery is aborted, we
8678 : : * recover back up to this point before allowing hot standby again.
8679 : : * This is important if the max_* settings are decreased, to ensure
8680 : : * you don't run queries against the WAL preceding the change. The
8681 : : * local copies cannot be updated as long as crash recovery is
8682 : : * happening and we expect all the WAL to be replayed.
8683 : : */
2810 michael@paquier.xyz 8684 [ + + ]: 38 : if (InArchiveRecovery)
8685 : : {
1488 heikki.linnakangas@i 8686 : 23 : LocalMinRecoveryPoint = ControlFile->minRecoveryPoint;
8687 : 23 : LocalMinRecoveryPointTLI = ControlFile->minRecoveryPointTLI;
8688 : : }
129 alvherre@kurilemu.de 8689 [ + + + + ]:GNC 38 : if (XLogRecPtrIsValid(LocalMinRecoveryPoint) && LocalMinRecoveryPoint < lsn)
8690 : : {
8691 : : TimeLineID replayTLI;
8692 : :
1488 heikki.linnakangas@i 8693 :CBC 12 : (void) GetCurrentReplayRecPtr(&replayTLI);
5795 8694 : 12 : ControlFile->minRecoveryPoint = lsn;
1591 rhaas@postgresql.org 8695 : 12 : ControlFile->minRecoveryPointTLI = replayTLI;
8696 : : }
8697 : :
3818 alvherre@alvh.no-ip. 8698 : 38 : CommitTsParameterChange(xlrec.track_commit_timestamp,
8699 : 38 : ControlFile->track_commit_timestamp);
8700 : 38 : ControlFile->track_commit_timestamp = xlrec.track_commit_timestamp;
8701 : :
5800 heikki.linnakangas@i 8702 : 38 : UpdateControlFile();
5795 8703 : 38 : LWLockRelease(ControlFileLock);
8704 : :
8705 : : /* Check to see if any parameter change gives a problem on recovery */
5800 8706 : 38 : CheckRequiredParameterValues();
8707 : : }
5163 simon@2ndQuadrant.co 8708 [ - + ]: 711 : else if (info == XLOG_FPW_CHANGE)
8709 : : {
8710 : : bool fpw;
8711 : :
5163 simon@2ndQuadrant.co 8712 :UBC 0 : memcpy(&fpw, XLogRecGetData(record), sizeof(bool));
8713 : :
8714 : : /*
8715 : : * Update the LSN of the last replayed XLOG_FPW_CHANGE record so that
8716 : : * do_pg_backup_start() and do_pg_backup_stop() can check whether
8717 : : * full_page_writes has been disabled during online backup.
8718 : : */
8719 [ # # ]: 0 : if (!fpw)
8720 : : {
4192 andres@anarazel.de 8721 [ # # ]: 0 : SpinLockAcquire(&XLogCtl->info_lck);
1572 rhaas@postgresql.org 8722 [ # # ]: 0 : if (XLogCtl->lastFpwDisableRecPtr < record->ReadRecPtr)
8723 : 0 : XLogCtl->lastFpwDisableRecPtr = record->ReadRecPtr;
4192 andres@anarazel.de 8724 : 0 : SpinLockRelease(&XLogCtl->info_lck);
8725 : : }
8726 : :
8727 : : /* Keep track of full_page_writes */
5163 simon@2ndQuadrant.co 8728 : 0 : lastFullPageWrites = fpw;
8729 : : }
878 rhaas@postgresql.org 8730 [ + + ]:GIC 711 : else if (info == XLOG_CHECKPOINT_REDO)
8731 : : {
8732 : : /* nothing to do here, just for informational purposes */
8733 : : }
82 msawada@postgresql.o 8734 [ + - ]:GNC 18 : else if (info == XLOG_LOGICAL_DECODING_STATUS_CHANGE)
8735 : : {
8736 : : bool status;
8737 : :
8738 : 18 : memcpy(&status, XLogRecGetData(record), sizeof(bool));
8739 : :
8740 : : /*
8741 : : * We need to toggle the logical decoding status and update the
8742 : : * XLogLogicalInfo cache of processes synchronously because
8743 : : * XLogLogicalInfoActive() is used even during read-only queries
8744 : : * (e.g., via RelationIsAccessibleInLogicalDecoding()). In the
8745 : : * 'disable' case, it is safe to invalidate existing slots after
8746 : : * disabling logical decoding because logical decoding cannot process
8747 : : * subsequent WAL records, which may not contain logical information.
8748 : : */
8749 [ + + ]: 18 : if (status)
8750 : 9 : EnableLogicalDecoding();
8751 : : else
8752 : 9 : DisableLogicalDecoding();
8753 : :
8754 [ + + ]: 18 : elog(DEBUG1, "update logical decoding status to %d during recovery",
8755 : : status);
8756 : :
8757 [ + - + + ]: 18 : if (InRecovery && InHotStandby)
8758 : : {
8759 [ + + ]: 16 : if (!status)
8760 : : {
8761 : : /*
8762 : : * Invalidate logical slots if we are in hot standby and the
8763 : : * primary disabled logical decoding.
8764 : : */
8765 : 9 : InvalidateObsoleteReplicationSlots(RS_INVAL_WAL_LEVEL,
8766 : : 0, InvalidOid,
8767 : : InvalidTransactionId);
8768 : : }
8769 [ - + ]: 7 : else if (sync_replication_slots)
8770 : : {
8771 : : /*
8772 : : * Signal the postmaster to launch the slotsync worker.
8773 : : *
8774 : : * XXX: For simplicity, we keep the slotsync worker running
8775 : : * even after logical decoding is disabled. A future
8776 : : * improvement can consider starting and stopping the worker
8777 : : * based on logical decoding status change.
8778 : : */
82 msawada@postgresql.o 8779 :UNC 0 : kill(PostmasterPid, SIGUSR1);
8780 : : }
8781 : : }
8782 : : }
9276 vadim4o@yahoo.com 8783 :CBC 107713 : }
8784 : :
8785 : : /*
8786 : : * Return the extra open flags used for opening a file, depending on the
8787 : : * value of the GUCs wal_sync_method, fsync and debug_io_direct.
8788 : : */
8789 : : static int
6514 magnus@hagander.net 8790 : 16482 : get_sync_bit(int method)
8791 : : {
5861 bruce@momjian.us 8792 : 16482 : int o_direct_flag = 0;
8793 : :
8794 : : /*
8795 : : * Use O_DIRECT if requested, except in walreceiver process. The WAL
8796 : : * written by walreceiver is normally read by the startup process soon
8797 : : * after it's written. Also, walreceiver performs unaligned writes, which
8798 : : * don't work with O_DIRECT, so it is required for correctness too.
8799 : : */
1072 tmunro@postgresql.or 8800 [ + + + - ]: 16482 : if ((io_direct_flags & IO_DIRECT_WAL) && !AmWalReceiverProcess())
5868 heikki.linnakangas@i 8801 : 8 : o_direct_flag = PG_O_DIRECT;
8802 : :
8803 : : /* If fsync is disabled, never open in sync mode */
1072 tmunro@postgresql.or 8804 [ + - ]: 16482 : if (!enableFsync)
8805 : 16482 : return o_direct_flag;
8806 : :
6514 magnus@hagander.net 8807 [ # # # # ]:UBC 0 : switch (method)
8808 : : {
8809 : : /*
8810 : : * enum values for all sync options are defined even if they are
8811 : : * not supported on the current platform. But if not, they are
8812 : : * not included in the enum option array, and therefore will never
8813 : : * be seen here.
8814 : : */
884 nathan@postgresql.or 8815 : 0 : case WAL_SYNC_METHOD_FSYNC:
8816 : : case WAL_SYNC_METHOD_FSYNC_WRITETHROUGH:
8817 : : case WAL_SYNC_METHOD_FDATASYNC:
1072 tmunro@postgresql.or 8818 : 0 : return o_direct_flag;
8819 : : #ifdef O_SYNC
884 nathan@postgresql.or 8820 : 0 : case WAL_SYNC_METHOD_OPEN:
1332 tmunro@postgresql.or 8821 : 0 : return O_SYNC | o_direct_flag;
8822 : : #endif
8823 : : #ifdef O_DSYNC
884 nathan@postgresql.or 8824 : 0 : case WAL_SYNC_METHOD_OPEN_DSYNC:
1332 tmunro@postgresql.or 8825 : 0 : return O_DSYNC | o_direct_flag;
8826 : : #endif
6516 magnus@hagander.net 8827 : 0 : default:
8828 : : /* can't happen (unless we are out of sync with option array) */
667 peter@eisentraut.org 8829 [ # # ]: 0 : elog(ERROR, "unrecognized \"wal_sync_method\": %d", method);
8830 : : return 0; /* silence warning */
8831 : : }
8832 : : }
8833 : :
8834 : : /*
8835 : : * GUC support
8836 : : */
8837 : : void
884 nathan@postgresql.or 8838 :CBC 1184 : assign_wal_sync_method(int new_wal_sync_method, void *extra)
8839 : : {
8840 [ - + ]: 1184 : if (wal_sync_method != new_wal_sync_method)
8841 : : {
8842 : : /*
8843 : : * To ensure that no blocks escape unsynced, force an fsync on the
8844 : : * currently open log segment (if any). Also, if the open flag is
8845 : : * changing, close the log file so it will be reopened (with new flag
8846 : : * bit) at next use.
8847 : : */
9130 tgl@sss.pgh.pa.us 8848 [ # # ]:UBC 0 : if (openLogFile >= 0)
8849 : : {
3284 rhaas@postgresql.org 8850 : 0 : pgstat_report_wait_start(WAIT_EVENT_WAL_SYNC_METHOD_ASSIGN);
9130 tgl@sss.pgh.pa.us 8851 [ # # ]: 0 : if (pg_fsync(openLogFile) != 0)
8852 : : {
8853 : : char xlogfname[MAXFNAMELEN];
8854 : : int save_errno;
8855 : :
2294 michael@paquier.xyz 8856 : 0 : save_errno = errno;
1591 rhaas@postgresql.org 8857 : 0 : XLogFileName(xlogfname, openLogTLI, openLogSegNo,
8858 : : wal_segment_size);
2294 michael@paquier.xyz 8859 : 0 : errno = save_errno;
8273 tgl@sss.pgh.pa.us 8860 [ # # ]: 0 : ereport(PANIC,
8861 : : (errcode_for_file_access(),
8862 : : errmsg("could not fsync file \"%s\": %m", xlogfname)));
8863 : : }
8864 : :
3284 rhaas@postgresql.org 8865 : 0 : pgstat_report_wait_end();
884 nathan@postgresql.or 8866 [ # # ]: 0 : if (get_sync_bit(wal_sync_method) != get_sync_bit(new_wal_sync_method))
7213 bruce@momjian.us 8867 : 0 : XLogFileClose();
8868 : : }
8869 : : }
9130 tgl@sss.pgh.pa.us 8870 :CBC 1184 : }
8871 : :
8872 : :
8873 : : /*
8874 : : * Issue appropriate kind of fsync (if any) for an XLOG output file.
8875 : : *
8876 : : * 'fd' is a file descriptor for the XLOG file to be fsync'd.
8877 : : * 'segno' is for error reporting purposes.
8878 : : */
8879 : : void
1591 rhaas@postgresql.org 8880 : 172278 : issue_xlog_fsync(int fd, XLogSegNo segno, TimeLineID tli)
8881 : : {
2294 michael@paquier.xyz 8882 : 172278 : char *msg = NULL;
8883 : : instr_time start;
8884 : :
1591 rhaas@postgresql.org 8885 [ - + ]: 172278 : Assert(tli != 0);
8886 : :
8887 : : /*
8888 : : * Quick exit if fsync is disabled or write() has already synced the WAL
8889 : : * file.
8890 : : */
1832 fujii@postgresql.org 8891 [ - + ]: 172278 : if (!enableFsync ||
884 nathan@postgresql.or 8892 [ # # ]:UBC 0 : wal_sync_method == WAL_SYNC_METHOD_OPEN ||
8893 [ # # ]: 0 : wal_sync_method == WAL_SYNC_METHOD_OPEN_DSYNC)
1832 fujii@postgresql.org 8894 :CBC 172278 : return;
8895 : :
8896 : : /*
8897 : : * Measure I/O timing to sync the WAL file for pg_stat_io.
8898 : : */
382 michael@paquier.xyz 8899 :UBC 0 : start = pgstat_prepare_io_time(track_wal_io_timing);
8900 : :
2813 8901 : 0 : pgstat_report_wait_start(WAIT_EVENT_WAL_SYNC);
884 nathan@postgresql.or 8902 [ # # # # ]: 0 : switch (wal_sync_method)
8903 : : {
8904 : 0 : case WAL_SYNC_METHOD_FSYNC:
5903 heikki.linnakangas@i 8905 [ # # ]: 0 : if (pg_fsync_no_writethrough(fd) != 0)
2294 michael@paquier.xyz 8906 : 0 : msg = _("could not fsync file \"%s\": %m");
9130 tgl@sss.pgh.pa.us 8907 : 0 : break;
8908 : : #ifdef HAVE_FSYNC_WRITETHROUGH
8909 : : case WAL_SYNC_METHOD_FSYNC_WRITETHROUGH:
8910 : : if (pg_fsync_writethrough(fd) != 0)
8911 : : msg = _("could not fsync write-through file \"%s\": %m");
8912 : : break;
8913 : : #endif
884 nathan@postgresql.or 8914 : 0 : case WAL_SYNC_METHOD_FDATASYNC:
5903 heikki.linnakangas@i 8915 [ # # ]: 0 : if (pg_fdatasync(fd) != 0)
2294 michael@paquier.xyz 8916 : 0 : msg = _("could not fdatasync file \"%s\": %m");
9130 tgl@sss.pgh.pa.us 8917 : 0 : break;
884 nathan@postgresql.or 8918 : 0 : case WAL_SYNC_METHOD_OPEN:
8919 : : case WAL_SYNC_METHOD_OPEN_DSYNC:
8920 : : /* not reachable */
1832 fujii@postgresql.org 8921 : 0 : Assert(false);
8922 : : break;
9130 tgl@sss.pgh.pa.us 8923 : 0 : default:
711 dgustafsson@postgres 8924 [ # # ]: 0 : ereport(PANIC,
8925 : : errcode(ERRCODE_INVALID_PARAMETER_VALUE),
8926 : : errmsg_internal("unrecognized \"wal_sync_method\": %d", wal_sync_method));
8927 : : break;
8928 : : }
8929 : :
8930 : : /* PANIC if failed to fsync */
2294 michael@paquier.xyz 8931 [ # # ]: 0 : if (msg)
8932 : : {
8933 : : char xlogfname[MAXFNAMELEN];
8934 : 0 : int save_errno = errno;
8935 : :
1591 rhaas@postgresql.org 8936 : 0 : XLogFileName(xlogfname, tli, segno, wal_segment_size);
2294 michael@paquier.xyz 8937 : 0 : errno = save_errno;
8938 [ # # ]: 0 : ereport(PANIC,
8939 : : (errcode_for_file_access(),
8940 : : errmsg(msg, xlogfname)));
8941 : : }
8942 : :
8943 : 0 : pgstat_report_wait_end();
8944 : :
404 8945 : 0 : pgstat_count_io_op_time(IOOBJECT_WAL, IOCONTEXT_NORMAL, IOOP_FSYNC,
8946 : : start, 1, 0);
8947 : : }
8948 : :
8949 : : /*
8950 : : * do_pg_backup_start is the workhorse of the user-visible pg_backup_start()
8951 : : * function. It creates the necessary starting checkpoint and constructs the
8952 : : * backup state and tablespace map.
8953 : : *
8954 : : * Input parameters are "state" (the backup state), "fast" (if true, we do
8955 : : * the checkpoint in fast mode), and "tablespaces" (if non-NULL, indicates a
8956 : : * list of tablespaceinfo structs describing the cluster's tablespaces.).
8957 : : *
8958 : : * The tablespace map contents are appended to passed-in parameter
8959 : : * tablespace_map and the caller is responsible for including it in the backup
8960 : : * archive as 'tablespace_map'. The tablespace_map file is required mainly for
8961 : : * tar format in windows as native windows utilities are not able to create
8962 : : * symlinks while extracting files from tar. However for consistency and
8963 : : * platform-independence, we do it the same way everywhere.
8964 : : *
8965 : : * It fills in "state" with the information required for the backup, such
8966 : : * as the minimum WAL location that must be present to restore from this
8967 : : * backup (starttli) and the corresponding timeline ID (starttli).
8968 : : *
8969 : : * Every successfully started backup must be stopped by calling
8970 : : * do_pg_backup_stop() or do_pg_abort_backup(). There can be many
8971 : : * backups active at the same time.
8972 : : *
8973 : : * It is the responsibility of the caller of this function to verify the
8974 : : * permissions of the calling user!
8975 : : */
8976 : : void
1266 michael@paquier.xyz 8977 :CBC 178 : do_pg_backup_start(const char *backupidstr, bool fast, List **tablespaces,
8978 : : BackupState *state, StringInfo tblspcmapfile)
8979 : : {
8980 : : bool backup_started_in_recovery;
8981 : :
8982 [ - + ]: 178 : Assert(state != NULL);
5163 simon@2ndQuadrant.co 8983 : 178 : backup_started_in_recovery = RecoveryInProgress();
8984 : :
8985 : : /*
8986 : : * During recovery, we don't need to check WAL level. Because, if WAL
8987 : : * level is not sufficient, it's impossible to get here during recovery.
8988 : : */
8989 [ + + - + ]: 178 : if (!backup_started_in_recovery && !XLogIsNeeded())
6745 tgl@sss.pgh.pa.us 8990 [ # # ]:UBC 0 : ereport(ERROR,
8991 : : (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
8992 : : errmsg("WAL level not sufficient for making an online backup"),
8993 : : errhint("\"wal_level\" must be set to \"replica\" or \"logical\" at server start.")));
8994 : :
5522 heikki.linnakangas@i 8995 [ + + ]:CBC 178 : if (strlen(backupidstr) > MAXPGPATH)
8996 [ + - ]: 1 : ereport(ERROR,
8997 : : (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
8998 : : errmsg("backup label too long (max %d bytes)",
8999 : : MAXPGPATH)));
9000 : :
621 dgustafsson@postgres 9001 : 177 : strlcpy(state->name, backupidstr, sizeof(state->name));
9002 : :
9003 : : /*
9004 : : * Mark backup active in shared memory. We must do full-page WAL writes
9005 : : * during an on-line backup even if not doing so at other times, because
9006 : : * it's quite possible for the backup dump to obtain a "torn" (partially
9007 : : * written) copy of a database page if it reads the page concurrently with
9008 : : * our write to the same page. This can be fixed as long as the first
9009 : : * write to the page in the WAL sequence is a full-page write. Hence, we
9010 : : * increment runningBackups then force a CHECKPOINT, to ensure there are
9011 : : * no dirty pages in shared memory that might get dumped while the backup
9012 : : * is in progress without having a corresponding WAL record. (Once the
9013 : : * backup is complete, we need not force full-page writes anymore, since
9014 : : * we expect that any pages not modified during the backup interval must
9015 : : * have been correctly captured by the backup.)
9016 : : *
9017 : : * Note that forcing full-page writes has no effect during an online
9018 : : * backup from the standby.
9019 : : *
9020 : : * We must hold all the insertion locks to change the value of
9021 : : * runningBackups, to ensure adequate interlocking against
9022 : : * XLogInsertRecord().
9023 : : */
4377 heikki.linnakangas@i 9024 : 177 : WALInsertLockAcquireExclusive();
1439 sfrost@snowman.net 9025 : 177 : XLogCtl->Insert.runningBackups++;
4377 heikki.linnakangas@i 9026 : 177 : WALInsertLockRelease();
9027 : :
9028 : : /*
9029 : : * Ensure we decrement runningBackups if we fail below. NB -- for this to
9030 : : * work correctly, it is critical that sessionBackupState is only updated
9031 : : * after this block is over.
9032 : : */
222 peter@eisentraut.org 9033 [ + - ]:GNC 177 : PG_ENSURE_ERROR_CLEANUP(do_pg_abort_backup, BoolGetDatum(true));
9034 : : {
5453 bruce@momjian.us 9035 :CBC 177 : bool gotUniqueStartpoint = false;
9036 : : DIR *tblspcdir;
9037 : : struct dirent *de;
9038 : : tablespaceinfo *ti;
9039 : : int datadirpathlen;
9040 : :
9041 : : /*
9042 : : * Force an XLOG file switch before the checkpoint, to ensure that the
9043 : : * WAL segment the checkpoint is written to doesn't contain pages with
9044 : : * old timeline IDs. That would otherwise happen if you called
9045 : : * pg_backup_start() right after restoring from a PITR archive: the
9046 : : * first WAL segment containing the startup checkpoint has pages in
9047 : : * the beginning with the old timeline ID. That can cause trouble at
9048 : : * recovery: we won't have a history file covering the old timeline if
9049 : : * pg_wal directory was not included in the base backup and the WAL
9050 : : * archive was cleared too before starting the backup.
9051 : : *
9052 : : * During recovery, we skip forcing XLOG file switch, which means that
9053 : : * the backup taken during recovery is not available for the special
9054 : : * recovery case described above.
9055 : : */
5163 simon@2ndQuadrant.co 9056 [ + + ]: 177 : if (!backup_started_in_recovery)
3370 andres@anarazel.de 9057 : 169 : RequestXLogSwitch(false);
9058 : :
9059 : : do
9060 : : {
9061 : : bool checkpointfpw;
9062 : :
9063 : : /*
9064 : : * Force a CHECKPOINT. Aside from being necessary to prevent torn
9065 : : * page problems, this guarantees that two successive backup runs
9066 : : * will have different checkpoint positions and hence different
9067 : : * history file names, even if nothing happened in between.
9068 : : *
9069 : : * During recovery, establish a restartpoint if possible. We use
9070 : : * the last restartpoint as the backup starting checkpoint. This
9071 : : * means that two successive backup runs can have same checkpoint
9072 : : * positions.
9073 : : *
9074 : : * Since the fact that we are executing do_pg_backup_start()
9075 : : * during recovery means that checkpointer is running, we can use
9076 : : * RequestCheckpoint() to establish a restartpoint.
9077 : : *
9078 : : * We use CHECKPOINT_FAST only if requested by user (via passing
9079 : : * fast = true). Otherwise this can take awhile.
9080 : : */
5473 heikki.linnakangas@i 9081 [ + + ]: 177 : RequestCheckpoint(CHECKPOINT_FORCE | CHECKPOINT_WAIT |
9082 : : (fast ? CHECKPOINT_FAST : 0));
9083 : :
9084 : : /*
9085 : : * Now we need to fetch the checkpoint record location, and also
9086 : : * its REDO pointer. The oldest point in WAL that would be needed
9087 : : * to restore starting from the checkpoint is precisely the REDO
9088 : : * pointer.
9089 : : */
9090 : 177 : LWLockAcquire(ControlFileLock, LW_SHARED);
1266 michael@paquier.xyz 9091 : 177 : state->checkpointloc = ControlFile->checkPoint;
9092 : 177 : state->startpoint = ControlFile->checkPointCopy.redo;
9093 : 177 : state->starttli = ControlFile->checkPointCopy.ThisTimeLineID;
5163 simon@2ndQuadrant.co 9094 : 177 : checkpointfpw = ControlFile->checkPointCopy.fullPageWrites;
5473 heikki.linnakangas@i 9095 : 177 : LWLockRelease(ControlFileLock);
9096 : :
5163 simon@2ndQuadrant.co 9097 [ + + ]: 177 : if (backup_started_in_recovery)
9098 : : {
9099 : : XLogRecPtr recptr;
9100 : :
9101 : : /*
9102 : : * Check to see if all WAL replayed during online backup
9103 : : * (i.e., since last restartpoint used as backup starting
9104 : : * checkpoint) contain full-page writes.
9105 : : */
4192 andres@anarazel.de 9106 [ - + ]: 8 : SpinLockAcquire(&XLogCtl->info_lck);
9107 : 8 : recptr = XLogCtl->lastFpwDisableRecPtr;
9108 : 8 : SpinLockRelease(&XLogCtl->info_lck);
9109 : :
1266 michael@paquier.xyz 9110 [ + - - + ]: 8 : if (!checkpointfpw || state->startpoint <= recptr)
5163 simon@2ndQuadrant.co 9111 [ # # ]:UBC 0 : ereport(ERROR,
9112 : : (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
9113 : : errmsg("WAL generated with \"full_page_writes=off\" was replayed "
9114 : : "since last restartpoint"),
9115 : : errhint("This means that the backup being taken on the standby "
9116 : : "is corrupt and should not be used. "
9117 : : "Enable \"full_page_writes\" and run CHECKPOINT on the primary, "
9118 : : "and then try an online backup again.")));
9119 : :
9120 : : /*
9121 : : * During recovery, since we don't use the end-of-backup WAL
9122 : : * record and don't write the backup history file, the
9123 : : * starting WAL location doesn't need to be unique. This means
9124 : : * that two base backups started at the same time might use
9125 : : * the same checkpoint as starting locations.
9126 : : */
5163 simon@2ndQuadrant.co 9127 :CBC 8 : gotUniqueStartpoint = true;
9128 : : }
9129 : :
9130 : : /*
9131 : : * If two base backups are started at the same time (in WAL sender
9132 : : * processes), we need to make sure that they use different
9133 : : * checkpoints as starting locations, because we use the starting
9134 : : * WAL location as a unique identifier for the base backup in the
9135 : : * end-of-backup WAL record and when we write the backup history
9136 : : * file. Perhaps it would be better generate a separate unique ID
9137 : : * for each backup instead of forcing another checkpoint, but
9138 : : * taking a checkpoint right after another is not that expensive
9139 : : * either because only few buffers have been dirtied yet.
9140 : : */
4377 heikki.linnakangas@i 9141 : 177 : WALInsertLockAcquireExclusive();
1266 michael@paquier.xyz 9142 [ + - ]: 177 : if (XLogCtl->Insert.lastBackupStart < state->startpoint)
9143 : : {
9144 : 177 : XLogCtl->Insert.lastBackupStart = state->startpoint;
5473 heikki.linnakangas@i 9145 : 177 : gotUniqueStartpoint = true;
9146 : : }
4377 9147 : 177 : WALInsertLockRelease();
5453 bruce@momjian.us 9148 [ - + ]: 177 : } while (!gotUniqueStartpoint);
9149 : :
9150 : : /*
9151 : : * Construct tablespace_map file.
9152 : : */
3960 andrew@dunslane.net 9153 : 177 : datadirpathlen = strlen(DataDir);
9154 : :
9155 : : /* Collect information about all tablespaces */
558 michael@paquier.xyz 9156 : 177 : tblspcdir = AllocateDir(PG_TBLSPC_DIR);
9157 [ + + ]: 570 : while ((de = ReadDir(tblspcdir, PG_TBLSPC_DIR)) != NULL)
9158 : : {
9159 : : char fullpath[MAXPGPATH + sizeof(PG_TBLSPC_DIR)];
9160 : : char linkpath[MAXPGPATH];
3960 andrew@dunslane.net 9161 : 393 : char *relpath = NULL;
9162 : : char *s;
9163 : : PGFileType de_type;
9164 : : char *badp;
9165 : : Oid tsoid;
9166 : :
9167 : : /*
9168 : : * Try to parse the directory name as an unsigned integer.
9169 : : *
9170 : : * Tablespace directories should be positive integers that can be
9171 : : * represented in 32 bits, with no leading zeroes or trailing
9172 : : * garbage. If we come across a name that doesn't meet those
9173 : : * criteria, skip it.
9174 : : */
874 rhaas@postgresql.org 9175 [ + + - + ]: 393 : if (de->d_name[0] < '1' || de->d_name[1] > '9')
9176 : 354 : continue;
9177 : 39 : errno = 0;
9178 : 39 : tsoid = strtoul(de->d_name, &badp, 10);
9179 [ + - + - : 39 : if (*badp != '\0' || errno == EINVAL || errno == ERANGE)
- + ]
3960 andrew@dunslane.net 9180 :UBC 0 : continue;
9181 : :
558 michael@paquier.xyz 9182 :CBC 39 : snprintf(fullpath, sizeof(fullpath), "%s/%s", PG_TBLSPC_DIR, de->d_name);
9183 : :
1062 rhaas@postgresql.org 9184 : 39 : de_type = get_dirent_type(fullpath, de, false, ERROR);
9185 : :
9186 [ + + ]: 39 : if (de_type == PGFILETYPE_LNK)
9187 : : {
9188 : : StringInfoData escapedpath;
9189 : : int rllen;
9190 : :
9191 : 25 : rllen = readlink(fullpath, linkpath, sizeof(linkpath));
9192 [ - + ]: 25 : if (rllen < 0)
9193 : : {
1062 rhaas@postgresql.org 9194 [ # # ]:UBC 0 : ereport(WARNING,
9195 : : (errmsg("could not read symbolic link \"%s\": %m",
9196 : : fullpath)));
9197 : 0 : continue;
9198 : : }
1062 rhaas@postgresql.org 9199 [ - + ]:CBC 25 : else if (rllen >= sizeof(linkpath))
9200 : : {
1062 rhaas@postgresql.org 9201 [ # # ]:UBC 0 : ereport(WARNING,
9202 : : (errmsg("symbolic link \"%s\" target is too long",
9203 : : fullpath)));
9204 : 0 : continue;
9205 : : }
1062 rhaas@postgresql.org 9206 :CBC 25 : linkpath[rllen] = '\0';
9207 : :
9208 : : /*
9209 : : * Relpath holds the relative path of the tablespace directory
9210 : : * when it's located within PGDATA, or NULL if it's located
9211 : : * elsewhere.
9212 : : */
9213 [ - + ]: 25 : if (rllen > datadirpathlen &&
1062 rhaas@postgresql.org 9214 [ # # ]:UBC 0 : strncmp(linkpath, DataDir, datadirpathlen) == 0 &&
1031 tgl@sss.pgh.pa.us 9215 [ # # ]: 0 : IS_DIR_SEP(linkpath[datadirpathlen]))
1062 rhaas@postgresql.org 9216 : 0 : relpath = pstrdup(linkpath + datadirpathlen + 1);
9217 : :
9218 : : /*
9219 : : * Add a backslash-escaped version of the link path to the
9220 : : * tablespace map file.
9221 : : */
1062 rhaas@postgresql.org 9222 :CBC 25 : initStringInfo(&escapedpath);
9223 [ + + ]: 594 : for (s = linkpath; *s; s++)
9224 : : {
9225 [ + - + - : 569 : if (*s == '\n' || *s == '\r' || *s == '\\')
- + ]
1062 rhaas@postgresql.org 9226 :UBC 0 : appendStringInfoChar(&escapedpath, '\\');
1062 rhaas@postgresql.org 9227 :CBC 569 : appendStringInfoChar(&escapedpath, *s);
9228 : : }
9229 : 25 : appendStringInfo(tblspcmapfile, "%s %s\n",
9230 : 25 : de->d_name, escapedpath.data);
9231 : 25 : pfree(escapedpath.data);
9232 : : }
9233 [ + - ]: 14 : else if (de_type == PGFILETYPE_DIR)
9234 : : {
9235 : : /*
9236 : : * It's possible to use allow_in_place_tablespaces to create
9237 : : * directories directly under pg_tblspc, for testing purposes
9238 : : * only.
9239 : : *
9240 : : * In this case, we store a relative path rather than an
9241 : : * absolute path into the tablespaceinfo.
9242 : : */
558 michael@paquier.xyz 9243 : 14 : snprintf(linkpath, sizeof(linkpath), "%s/%s",
9244 : 14 : PG_TBLSPC_DIR, de->d_name);
1062 rhaas@postgresql.org 9245 : 14 : relpath = pstrdup(linkpath);
9246 : : }
9247 : : else
9248 : : {
9249 : : /* Skip any other file type that appears here. */
1062 rhaas@postgresql.org 9250 :UBC 0 : continue;
9251 : : }
9252 : :
95 michael@paquier.xyz 9253 :GNC 39 : ti = palloc_object(tablespaceinfo);
874 rhaas@postgresql.org 9254 :CBC 39 : ti->oid = tsoid;
1824 tgl@sss.pgh.pa.us 9255 : 39 : ti->path = pstrdup(linkpath);
1062 rhaas@postgresql.org 9256 : 39 : ti->rpath = relpath;
2097 9257 : 39 : ti->size = -1;
9258 : :
3949 bruce@momjian.us 9259 [ + - ]: 39 : if (tablespaces)
9260 : 39 : *tablespaces = lappend(*tablespaces, ti);
9261 : : }
3023 tgl@sss.pgh.pa.us 9262 : 177 : FreeDir(tblspcdir);
9263 : :
1266 michael@paquier.xyz 9264 : 177 : state->starttime = (pg_time_t) time(NULL);
9265 : : }
222 peter@eisentraut.org 9266 [ - + ]:GNC 177 : PG_END_ENSURE_ERROR_CLEANUP(do_pg_abort_backup, BoolGetDatum(true));
9267 : :
1266 michael@paquier.xyz 9268 :CBC 177 : state->started_in_recovery = backup_started_in_recovery;
9269 : :
9270 : : /*
9271 : : * Mark that the start phase has correctly finished for the backup.
9272 : : */
1439 sfrost@snowman.net 9273 : 177 : sessionBackupState = SESSION_BACKUP_RUNNING;
7894 tgl@sss.pgh.pa.us 9274 : 177 : }
9275 : :
9276 : : /*
9277 : : * Utility routine to fetch the session-level status of a backup running.
9278 : : */
9279 : : SessionBackupState
3278 teodor@sigaev.ru 9280 : 198 : get_backup_status(void)
9281 : : {
9282 : 198 : return sessionBackupState;
9283 : : }
9284 : :
9285 : : /*
9286 : : * do_pg_backup_stop
9287 : : *
9288 : : * Utility function called at the end of an online backup. It creates history
9289 : : * file (if required), resets sessionBackupState and so on. It can optionally
9290 : : * wait for WAL segments to be archived.
9291 : : *
9292 : : * "state" is filled with the information necessary to restore from this
9293 : : * backup with its stop LSN (stoppoint), its timeline ID (stoptli), etc.
9294 : : *
9295 : : * It is the responsibility of the caller of this function to verify the
9296 : : * permissions of the calling user!
9297 : : */
9298 : : void
1266 michael@paquier.xyz 9299 : 171 : do_pg_backup_stop(BackupState *state, bool waitforarchive)
9300 : : {
9301 : 171 : bool backup_stopped_in_recovery = false;
9302 : : char histfilepath[MAXPGPATH];
9303 : : char lastxlogfilename[MAXFNAMELEN];
9304 : : char histfilename[MAXFNAMELEN];
9305 : : XLogSegNo _logSegNo;
9306 : : FILE *fp;
9307 : : int seconds_before_warning;
6553 bruce@momjian.us 9308 : 171 : int waits = 0;
5810 simon@2ndQuadrant.co 9309 : 171 : bool reported_waiting = false;
9310 : :
1266 michael@paquier.xyz 9311 [ - + ]: 171 : Assert(state != NULL);
9312 : :
9313 : 171 : backup_stopped_in_recovery = RecoveryInProgress();
9314 : :
9315 : : /*
9316 : : * During recovery, we don't need to check WAL level. Because, if WAL
9317 : : * level is not sufficient, it's impossible to get here during recovery.
9318 : : */
9319 [ + + - + ]: 171 : if (!backup_stopped_in_recovery && !XLogIsNeeded())
6397 tgl@sss.pgh.pa.us 9320 [ # # ]:UBC 0 : ereport(ERROR,
9321 : : (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
9322 : : errmsg("WAL level not sufficient for making an online backup"),
9323 : : errhint("\"wal_level\" must be set to \"replica\" or \"logical\" at server start.")));
9324 : :
9325 : : /*
9326 : : * OK to update backup counter and session-level lock.
9327 : : *
9328 : : * Note that CHECK_FOR_INTERRUPTS() must not occur while updating them,
9329 : : * otherwise they can be updated inconsistently, which might cause
9330 : : * do_pg_abort_backup() to fail.
9331 : : */
3344 fujii@postgresql.org 9332 :CBC 171 : WALInsertLockAcquireExclusive();
9333 : :
9334 : : /*
9335 : : * It is expected that each do_pg_backup_start() call is matched by
9336 : : * exactly one do_pg_backup_stop() call.
9337 : : */
1439 sfrost@snowman.net 9338 [ - + ]: 171 : Assert(XLogCtl->Insert.runningBackups > 0);
9339 : 171 : XLogCtl->Insert.runningBackups--;
9340 : :
9341 : : /*
9342 : : * Clean up session-level lock.
9343 : : *
9344 : : * You might think that WALInsertLockRelease() can be called before
9345 : : * cleaning up session-level lock because session-level lock doesn't need
9346 : : * to be protected with WAL insertion lock. But since
9347 : : * CHECK_FOR_INTERRUPTS() can occur in it, session-level lock must be
9348 : : * cleaned up before it.
9349 : : */
3278 teodor@sigaev.ru 9350 : 171 : sessionBackupState = SESSION_BACKUP_NONE;
9351 : :
3008 fujii@postgresql.org 9352 : 171 : WALInsertLockRelease();
9353 : :
9354 : : /*
9355 : : * If we are taking an online backup from the standby, we confirm that the
9356 : : * standby has not been promoted during the backup.
9357 : : */
1266 michael@paquier.xyz 9358 [ + + - + ]: 171 : if (state->started_in_recovery && !backup_stopped_in_recovery)
5163 simon@2ndQuadrant.co 9359 [ # # ]:UBC 0 : ereport(ERROR,
9360 : : (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
9361 : : errmsg("the standby was promoted during online backup"),
9362 : : errhint("This means that the backup being taken is corrupt "
9363 : : "and should not be used. "
9364 : : "Try taking another online backup.")));
9365 : :
9366 : : /*
9367 : : * During recovery, we don't write an end-of-backup record. We assume that
9368 : : * pg_control was backed up last and its minimum recovery point can be
9369 : : * available as the backup end location. Since we don't have an
9370 : : * end-of-backup record, we use the pg_control value to check whether
9371 : : * we've reached the end of backup when starting recovery from this
9372 : : * backup. We have no way of checking if pg_control wasn't backed up last
9373 : : * however.
9374 : : *
9375 : : * We don't force a switch to new WAL file but it is still possible to
9376 : : * wait for all the required files to be archived if waitforarchive is
9377 : : * true. This is okay if we use the backup to start a standby and fetch
9378 : : * the missing WAL using streaming replication. But in the case of an
9379 : : * archive recovery, a user should set waitforarchive to true and wait for
9380 : : * them to be archived to ensure that all the required files are
9381 : : * available.
9382 : : *
9383 : : * We return the current minimum recovery point as the backup end
9384 : : * location. Note that it can be greater than the exact backup end
9385 : : * location if the minimum recovery point is updated after the backup of
9386 : : * pg_control. This is harmless for current uses.
9387 : : *
9388 : : * XXX currently a backup history file is for informational and debug
9389 : : * purposes only. It's not essential for an online backup. Furthermore,
9390 : : * even if it's created, it will not be archived during recovery because
9391 : : * an archiver is not invoked. So it doesn't seem worthwhile to write a
9392 : : * backup history file during recovery.
9393 : : */
1266 michael@paquier.xyz 9394 [ + + ]:CBC 171 : if (backup_stopped_in_recovery)
9395 : : {
9396 : : XLogRecPtr recptr;
9397 : :
9398 : : /*
9399 : : * Check to see if all WAL replayed during online backup contain
9400 : : * full-page writes.
9401 : : */
4192 andres@anarazel.de 9402 [ - + ]: 8 : SpinLockAcquire(&XLogCtl->info_lck);
9403 : 8 : recptr = XLogCtl->lastFpwDisableRecPtr;
9404 : 8 : SpinLockRelease(&XLogCtl->info_lck);
9405 : :
1266 michael@paquier.xyz 9406 [ - + ]: 8 : if (state->startpoint <= recptr)
5163 simon@2ndQuadrant.co 9407 [ # # ]:UBC 0 : ereport(ERROR,
9408 : : (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
9409 : : errmsg("WAL generated with \"full_page_writes=off\" was replayed "
9410 : : "during online backup"),
9411 : : errhint("This means that the backup being taken on the standby "
9412 : : "is corrupt and should not be used. "
9413 : : "Enable \"full_page_writes\" and run CHECKPOINT on the primary, "
9414 : : "and then try an online backup again.")));
9415 : :
9416 : :
5163 simon@2ndQuadrant.co 9417 :CBC 8 : LWLockAcquire(ControlFileLock, LW_SHARED);
1266 michael@paquier.xyz 9418 : 8 : state->stoppoint = ControlFile->minRecoveryPoint;
9419 : 8 : state->stoptli = ControlFile->minRecoveryPointTLI;
5163 simon@2ndQuadrant.co 9420 : 8 : LWLockRelease(ControlFileLock);
9421 : : }
9422 : : else
9423 : : {
9424 : : char *history_file;
9425 : :
9426 : : /*
9427 : : * Write the backup-end xlog record
9428 : : */
3144 rhaas@postgresql.org 9429 : 163 : XLogBeginInsert();
397 peter@eisentraut.org 9430 : 163 : XLogRegisterData(&state->startpoint,
9431 : : sizeof(state->startpoint));
1266 michael@paquier.xyz 9432 : 163 : state->stoppoint = XLogInsert(RM_XLOG_ID, XLOG_BACKUP_END);
9433 : :
9434 : : /*
9435 : : * Given that we're not in recovery, InsertTimeLineID is set and can't
9436 : : * change, so we can read it without a lock.
9437 : : */
9438 : 163 : state->stoptli = XLogCtl->InsertTimeLineID;
9439 : :
9440 : : /*
9441 : : * Force a switch to a new xlog segment file, so that the backup is
9442 : : * valid as soon as archiver moves out the current segment file.
9443 : : */
3144 rhaas@postgresql.org 9444 : 163 : RequestXLogSwitch(false);
9445 : :
1266 michael@paquier.xyz 9446 : 163 : state->stoptime = (pg_time_t) time(NULL);
9447 : :
9448 : : /*
9449 : : * Write the backup history file
9450 : : */
9451 : 163 : XLByteToSeg(state->startpoint, _logSegNo, wal_segment_size);
9452 : 163 : BackupHistoryFilePath(histfilepath, state->stoptli, _logSegNo,
9453 : : state->startpoint, wal_segment_size);
3144 rhaas@postgresql.org 9454 : 163 : fp = AllocateFile(histfilepath, "w");
9455 [ - + ]: 163 : if (!fp)
3144 rhaas@postgresql.org 9456 [ # # ]:UBC 0 : ereport(ERROR,
9457 : : (errcode_for_file_access(),
9458 : : errmsg("could not create file \"%s\": %m",
9459 : : histfilepath)));
9460 : :
9461 : : /* Build and save the contents of the backup history file */
1266 michael@paquier.xyz 9462 :CBC 163 : history_file = build_backup_content(state, true);
1265 9463 : 163 : fprintf(fp, "%s", history_file);
1266 9464 : 163 : pfree(history_file);
9465 : :
3144 rhaas@postgresql.org 9466 [ + - + - : 163 : if (fflush(fp) || ferror(fp) || FreeFile(fp))
- + ]
3144 rhaas@postgresql.org 9467 [ # # ]:UBC 0 : ereport(ERROR,
9468 : : (errcode_for_file_access(),
9469 : : errmsg("could not write file \"%s\": %m",
9470 : : histfilepath)));
9471 : :
9472 : : /*
9473 : : * Clean out any no-longer-needed history files. As a side effect,
9474 : : * this will post a .ready file for the newly created history file,
9475 : : * notifying the archiver that history file may be archived
9476 : : * immediately.
9477 : : */
3144 rhaas@postgresql.org 9478 :CBC 163 : CleanupBackupHistory();
9479 : : }
9480 : :
9481 : : /*
9482 : : * If archiving is enabled, wait for all the required WAL files to be
9483 : : * archived before returning. If archiving isn't enabled, the required WAL
9484 : : * needs to be transported via streaming replication (hopefully with
9485 : : * wal_keep_size set high enough), or some more exotic mechanism like
9486 : : * polling and copying files from pg_wal with script. We have no knowledge
9487 : : * of those mechanisms, so it's up to the user to ensure that he gets all
9488 : : * the required WAL.
9489 : : *
9490 : : * We wait until both the last WAL file filled during backup and the
9491 : : * history file have been archived, and assume that the alphabetic sorting
9492 : : * property of the WAL files ensures any earlier WAL files are safely
9493 : : * archived as well.
9494 : : *
9495 : : * We wait forever, since archive_command is supposed to work and we
9496 : : * assume the admin wanted his backup to work completely. If you don't
9497 : : * wish to wait, then either waitforarchive should be passed in as false,
9498 : : * or you can set statement_timeout. Also, some notices are issued to
9499 : : * clue in anyone who might be doing this interactively.
9500 : : */
9501 : :
9502 [ + + ]: 171 : if (waitforarchive &&
1266 michael@paquier.xyz 9503 [ + + + + : 10 : ((!backup_stopped_in_recovery && XLogArchivingActive()) ||
- + + + +
+ ]
9504 [ + - - + : 1 : (backup_stopped_in_recovery && XLogArchivingAlways())))
- + ]
9505 : : {
9506 : 4 : XLByteToPrevSeg(state->stoppoint, _logSegNo, wal_segment_size);
9507 : 4 : XLogFileName(lastxlogfilename, state->stoptli, _logSegNo,
9508 : : wal_segment_size);
9509 : :
9510 : 4 : XLByteToSeg(state->startpoint, _logSegNo, wal_segment_size);
9511 : 4 : BackupHistoryFileName(histfilename, state->stoptli, _logSegNo,
9512 : : state->startpoint, wal_segment_size);
9513 : :
5731 bruce@momjian.us 9514 : 4 : seconds_before_warning = 60;
9515 : 4 : waits = 0;
9516 : :
9517 [ + + - + ]: 12 : while (XLogArchiveIsBusy(lastxlogfilename) ||
9518 : 4 : XLogArchiveIsBusy(histfilename))
9519 : : {
9520 [ - + ]: 4 : CHECK_FOR_INTERRUPTS();
9521 : :
9522 [ + - - + ]: 4 : if (!reported_waiting && waits > 5)
9523 : : {
5731 bruce@momjian.us 9524 [ # # ]:UBC 0 : ereport(NOTICE,
9525 : : (errmsg("base backup done, waiting for required WAL segments to be archived")));
9526 : 0 : reported_waiting = true;
9527 : : }
9528 : :
1713 michael@paquier.xyz 9529 :CBC 4 : (void) WaitLatch(MyLatch,
9530 : : WL_LATCH_SET | WL_TIMEOUT | WL_EXIT_ON_PM_DEATH,
9531 : : 1000L,
9532 : : WAIT_EVENT_BACKUP_WAIT_WAL_ARCHIVE);
9533 : 4 : ResetLatch(MyLatch);
9534 : :
5731 bruce@momjian.us 9535 [ - + ]: 4 : if (++waits >= seconds_before_warning)
9536 : : {
5731 bruce@momjian.us 9537 :UBC 0 : seconds_before_warning *= 2; /* This wraps in >10 years... */
9538 [ # # ]: 0 : ereport(WARNING,
9539 : : (errmsg("still waiting for all required WAL segments to be archived (%d seconds elapsed)",
9540 : : waits),
9541 : : errhint("Check that your \"archive_command\" is executing properly. "
9542 : : "You can safely cancel this backup, "
9543 : : "but the database backup will not be usable without all the WAL segments.")));
9544 : : }
9545 : : }
9546 : :
5731 bruce@momjian.us 9547 [ + + ]:CBC 4 : ereport(NOTICE,
9548 : : (errmsg("all required WAL segments have been archived")));
9549 : : }
5513 magnus@hagander.net 9550 [ + + ]: 167 : else if (waitforarchive)
5799 tgl@sss.pgh.pa.us 9551 [ + - ]: 6 : ereport(NOTICE,
9552 : : (errmsg("WAL archiving is not enabled; you must ensure that all required WAL segments are copied through other means to complete the backup")));
5544 magnus@hagander.net 9553 : 171 : }
9554 : :
9555 : :
9556 : : /*
9557 : : * do_pg_abort_backup: abort a running backup
9558 : : *
9559 : : * This does just the most basic steps of do_pg_backup_stop(), by taking the
9560 : : * system out of backup mode, thus making it a lot more safe to call from
9561 : : * an error handler.
9562 : : *
9563 : : * 'arg' indicates that it's being called during backup setup; so
9564 : : * sessionBackupState has not been modified yet, but runningBackups has
9565 : : * already been incremented. When it's false, then it's invoked as a
9566 : : * before_shmem_exit handler, and therefore we must not change state
9567 : : * unless sessionBackupState indicates that a backup is actually running.
9568 : : *
9569 : : * NB: This gets used as a PG_ENSURE_ERROR_CLEANUP callback and
9570 : : * before_shmem_exit handler, hence the odd-looking signature.
9571 : : */
9572 : : void
2278 rhaas@postgresql.org 9573 : 8 : do_pg_abort_backup(int code, Datum arg)
9574 : : {
1243 alvherre@alvh.no-ip. 9575 : 8 : bool during_backup_start = DatumGetBool(arg);
9576 : :
9577 : : /* If called during backup start, there shouldn't be one already running */
1238 9578 [ - + - - ]: 8 : Assert(!during_backup_start || sessionBackupState == SESSION_BACKUP_NONE);
9579 : :
1243 9580 [ + - + + ]: 8 : if (during_backup_start || sessionBackupState != SESSION_BACKUP_NONE)
9581 : : {
9582 : 6 : WALInsertLockAcquireExclusive();
9583 [ - + ]: 6 : Assert(XLogCtl->Insert.runningBackups > 0);
9584 : 6 : XLogCtl->Insert.runningBackups--;
9585 : :
9586 : 6 : sessionBackupState = SESSION_BACKUP_NONE;
9587 : 6 : WALInsertLockRelease();
9588 : :
9589 [ + - ]: 6 : if (!during_backup_start)
9590 [ + - ]: 6 : ereport(WARNING,
9591 : : errmsg("aborting backup due to backend exiting before pg_backup_stop was called"));
9592 : : }
2278 rhaas@postgresql.org 9593 : 8 : }
9594 : :
9595 : : /*
9596 : : * Register a handler that will warn about unterminated backups at end of
9597 : : * session, unless this has already been done.
9598 : : */
9599 : : void
9600 : 4 : register_persistent_abort_backup_handler(void)
9601 : : {
9602 : : static bool already_done = false;
9603 : :
9604 [ + + ]: 4 : if (already_done)
9605 : 1 : return;
222 peter@eisentraut.org 9606 :GNC 3 : before_shmem_exit(do_pg_abort_backup, BoolGetDatum(false));
2278 rhaas@postgresql.org 9607 :CBC 3 : already_done = true;
9608 : : }
9609 : :
9610 : : /*
9611 : : * Get latest WAL insert pointer
9612 : : */
9613 : : XLogRecPtr
5177 heikki.linnakangas@i 9614 : 8224 : GetXLogInsertRecPtr(void)
9615 : : {
4192 andres@anarazel.de 9616 : 8224 : XLogCtlInsert *Insert = &XLogCtl->Insert;
9617 : : uint64 current_bytepos;
9618 : :
4633 heikki.linnakangas@i 9619 [ + + ]: 8224 : SpinLockAcquire(&Insert->insertpos_lck);
9620 : 8224 : current_bytepos = Insert->CurrBytePos;
9621 : 8224 : SpinLockRelease(&Insert->insertpos_lck);
9622 : :
9623 : 8224 : return XLogBytePosToRecPtr(current_bytepos);
9624 : : }
9625 : :
9626 : : /*
9627 : : * Get latest WAL record end pointer
9628 : : */
9629 : : XLogRecPtr
2 tomas.vondra@postgre 9630 :GBC 321 : GetXLogInsertEndRecPtr(void)
9631 : : {
9632 : 321 : XLogCtlInsert *Insert = &XLogCtl->Insert;
9633 : : uint64 current_bytepos;
9634 : :
9635 [ # # ]: 321 : SpinLockAcquire(&Insert->insertpos_lck);
9636 : 321 : current_bytepos = Insert->CurrBytePos;
9637 : 321 : SpinLockRelease(&Insert->insertpos_lck);
9638 : :
9639 : 321 : return XLogBytePosToEndRecPtr(current_bytepos);
9640 : : }
9641 : :
9642 : : /*
9643 : : * Get latest WAL write pointer
9644 : : */
9645 : : XLogRecPtr
1488 heikki.linnakangas@i 9646 :CBC 4414 : GetXLogWriteRecPtr(void)
9647 : : {
711 alvherre@alvh.no-ip. 9648 : 4414 : RefreshXLogWriteResult(LogwrtResult);
9649 : :
1488 heikki.linnakangas@i 9650 : 4414 : return LogwrtResult.Write;
9651 : : }
9652 : :
9653 : : /*
9654 : : * Returns the redo pointer of the last checkpoint or restartpoint. This is
9655 : : * the oldest point in WAL that we still need, if we have to restart recovery.
9656 : : */
9657 : : void
9658 : 391 : GetOldestRestartPoint(XLogRecPtr *oldrecptr, TimeLineID *oldtli)
9659 : : {
9660 : 391 : LWLockAcquire(ControlFileLock, LW_SHARED);
9661 : 391 : *oldrecptr = ControlFile->checkPointCopy.redo;
9662 : 391 : *oldtli = ControlFile->checkPointCopy.ThisTimeLineID;
9663 : 391 : LWLockRelease(ControlFileLock);
7296 tgl@sss.pgh.pa.us 9664 : 391 : }
9665 : :
9666 : : /* Thin wrapper around ShutdownWalRcv(). */
9667 : : void
1721 noah@leadboat.com 9668 : 1001 : XLogShutdownWalRcv(void)
9669 : : {
130 michael@paquier.xyz 9670 [ + + - + ]:GNC 1001 : Assert(AmStartupProcess() || !IsUnderPostmaster);
9671 : :
1721 noah@leadboat.com 9672 :CBC 1001 : ShutdownWalRcv();
131 michael@paquier.xyz 9673 : 1001 : ResetInstallXLogFileSegmentActive();
1721 noah@leadboat.com 9674 : 1001 : }
9675 : :
9676 : : /* Enable WAL file recycling and preallocation. */
9677 : : void
1488 heikki.linnakangas@i 9678 : 1178 : SetInstallXLogFileSegmentActive(void)
9679 : : {
9680 : 1178 : LWLockAcquire(ControlFileLock, LW_EXCLUSIVE);
9681 : 1178 : XLogCtl->InstallXLogFileSegmentActive = true;
9682 : 1178 : LWLockRelease(ControlFileLock);
3840 fujii@postgresql.org 9683 : 1178 : }
9684 : :
9685 : : /* Disable WAL file recycling and preallocation. */
9686 : : void
131 michael@paquier.xyz 9687 : 1141 : ResetInstallXLogFileSegmentActive(void)
9688 : : {
9689 : 1141 : LWLockAcquire(ControlFileLock, LW_EXCLUSIVE);
9690 : 1141 : XLogCtl->InstallXLogFileSegmentActive = false;
9691 : 1141 : LWLockRelease(ControlFileLock);
9692 : 1141 : }
9693 : :
9694 : : bool
1488 heikki.linnakangas@i 9695 : 362 : IsInstallXLogFileSegmentActive(void)
9696 : : {
9697 : : bool result;
9698 : :
9699 : 362 : LWLockAcquire(ControlFileLock, LW_SHARED);
9700 : 362 : result = XLogCtl->InstallXLogFileSegmentActive;
9701 : 362 : LWLockRelease(ControlFileLock);
9702 : :
9703 : 362 : return result;
9704 : : }
9705 : :
9706 : : /*
9707 : : * Update the WalWriterSleeping flag.
9708 : : */
9709 : : void
5059 tgl@sss.pgh.pa.us 9710 : 536 : SetWalWriterSleeping(bool sleeping)
9711 : : {
4192 andres@anarazel.de 9712 [ - + ]: 536 : SpinLockAcquire(&XLogCtl->info_lck);
9713 : 536 : XLogCtl->WalWriterSleeping = sleeping;
9714 : 536 : SpinLockRelease(&XLogCtl->info_lck);
5059 tgl@sss.pgh.pa.us 9715 : 536 : }
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