Age Owner Branch data TLA Line data Source code
1 : : /*-------------------------------------------------------------------------
2 : : *
3 : : * datachecksum_state.c
4 : : * Background worker for enabling or disabling data checksums online as
5 : : * well as functionality for manipulating data checksum state
6 : : *
7 : : * When enabling data checksums on a cluster at initdb time or when shut down
8 : : * with pg_checksums, no extra process is required as each page is checksummed,
9 : : * and verified, when accessed. When enabling checksums on an already running
10 : : * cluster, this worker will ensure that all pages are checksummed before
11 : : * verification of the checksums is turned on. In the case of disabling
12 : : * checksums, the state transition is performed only in the control file, no
13 : : * changes are performed on the data pages.
14 : : *
15 : : * Checksums can be either enabled or disabled cluster-wide, with on/off being
16 : : * the end state for data_checksums.
17 : : *
18 : : * 1. Enabling checksums
19 : : * ---------------------
20 : : * When enabling checksums in an online cluster, data_checksums will be set to
21 : : * "inprogress-on" which signals that write operations MUST compute and write
22 : : * the checksum on the data page, but during reading the checksum SHALL NOT be
23 : : * verified. This ensures that all objects created during when checksums are
24 : : * being enabled will have checksums set, but reads won't fail due to missing or
25 : : * invalid checksums. Invalid checksums can be present in case the cluster had
26 : : * checksums enabled, then disabled them and updated the page while they were
27 : : * disabled.
28 : : *
29 : : * The DataChecksumsWorker will compile a list of all databases at the start,
30 : : * any databases created concurrently will see the in-progress state and will
31 : : * be checksummed automatically. All databases from the original list MUST BE
32 : : * successfully processed in order for data checksums to be enabled, the only
33 : : * exception are databases which are dropped before having been processed.
34 : : *
35 : : * For each database, all relations which have storage are read and every data
36 : : * page is marked dirty to force a write with the checksum. This will generate
37 : : * a lot of WAL as the entire database is read and written.
38 : : *
39 : : * If the processing is interrupted by a cluster crash or restart, it needs to
40 : : * be restarted from the beginning again as state isn't persisted.
41 : : *
42 : : * 2. Disabling checksums
43 : : * ----------------------
44 : : * When disabling checksums, data_checksums will be set to "inprogress-off"
45 : : * which signals that checksums are written but no longer need to be verified.
46 : : * This ensures that backends which have not yet transitioned to the
47 : : * "inprogress-off" state will still see valid checksums on pages.
48 : : *
49 : : * 3. Synchronization and Correctness
50 : : * ----------------------------------
51 : : * The processes involved in enabling or disabling data checksums in an
52 : : * online cluster must be properly synchronized with the normal backends
53 : : * serving concurrent queries to ensure correctness. Correctness is defined
54 : : * as the following:
55 : : *
56 : : * - Backends SHALL NOT violate the data_checksums state they have agreed to
57 : : * by acknowledging the procsignalbarrier: This means that all backends
58 : : * MUST calculate and write data checksums during all states except off;
59 : : * MUST validate checksums only in the 'on' state.
60 : : * - Data checksums SHALL NOT be considered enabled cluster-wide until all
61 : : * currently connected backends have state "on": This means that all
62 : : * backends must wait on the procsignalbarrier to be acknowledged by all
63 : : * before proceeding to validate data checksums.
64 : : *
65 : : * There are two steps of synchronization required for changing data_checksums
66 : : * in an online cluster: (i) changing state in the active backends ("on",
67 : : * "off", "inprogress-on" and "inprogress-off"), and (ii) ensuring no
68 : : * incompatible objects and processes are left in a database when workers end.
69 : : * The former deals with cluster-wide agreement on data checksum state and the
70 : : * latter with ensuring that any concurrent activity cannot break the data
71 : : * checksum contract during processing.
72 : : *
73 : : * Synchronizing the state change is done with procsignal barriers. Before
74 : : * updating the data_checksums state in the control file, all other backends must absorb the
75 : : * barrier. Barrier absorption will happen during interrupt processing, which
76 : : * means that connected backends will change state at different times. If
77 : : * waiting for a barrier is done during startup, for example during replay, it
78 : : * is important to realize that any locks held by the startup process might
79 : : * cause deadlocks if backends end up waiting for those locks while startup
80 : : * is waiting for a procsignalbarrier.
81 : : *
82 : : * 3.1 When Enabling Data Checksums
83 : : * --------------------------------
84 : : * A process which fails to observe data checksums being enabled can induce two
85 : : * types of errors: failing to write the checksum when modifying the page and
86 : : * failing to validate the data checksum on the page when reading it.
87 : : *
88 : : * When processing starts all backends belong to one of the below sets, with
89 : : * one of Bd and Bi being empty:
90 : : *
91 : : * Bg: Backend updating the global state and emitting the procsignalbarrier
92 : : * Bd: Backends in "off" state
93 : : * Bi: Backends in "inprogress-on" state
94 : : *
95 : : * If processing is started in an online cluster then all backends are in Bd.
96 : : * If processing was halted by the cluster shutting down (due to a crash or
97 : : * intentional restart), the controlfile state "inprogress-on" will be observed
98 : : * on system startup and all backends will be placed in Bd. The controlfile
99 : : * state will also be set to "off".
100 : : *
101 : : * Backends transition Bd -> Bi via a procsignalbarrier which is emitted by the
102 : : * DataChecksumsWorkerLauncherMain. When all backends have acknowledged the
103 : : * barrier then Bd will be empty and the next phase can begin: calculating and
104 : : * writing data checksums with DataChecksumsWorkers. When the
105 : : * DataChecksumsWorker processes have finished writing checksums on all pages,
106 : : * data checksums are enabled cluster-wide via another procsignalbarrier.
107 : : * There are four sets of backends where Bd shall be an empty set:
108 : : *
109 : : * Bg: Backend updating the global state and emitting the procsignalbarrier
110 : : * Bd: Backends in "off" state
111 : : * Be: Backends in "on" state
112 : : * Bi: Backends in "inprogress-on" state
113 : : *
114 : : * Backends in Bi and Be will write checksums when modifying a page, but only
115 : : * backends in Be will verify the checksum during reading. The Bg backend is
116 : : * blocked waiting for all backends in Bi to process interrupts and move to
117 : : * Be. Any backend starting while Bg is waiting on the procsignalbarrier will
118 : : * observe the global state being "on" and will thus automatically belong to
119 : : * Be. Checksums are enabled cluster-wide when Bi is an empty set. Bi and Be
120 : : * are compatible sets while still operating based on their local state as
121 : : * both write data checksums.
122 : : *
123 : : * 3.2 When Disabling Data Checksums
124 : : * ---------------------------------
125 : : * A process which fails to observe that data checksums have been disabled
126 : : * can induce two types of errors: writing the checksum when modifying the
127 : : * page and validating a data checksum which is no longer correct due to
128 : : * modifications to the page. The former is not an error per se as data
129 : : * integrity is maintained, but it is wasteful. The latter will cause errors
130 : : * in user operations. Assuming the following sets of backends:
131 : : *
132 : : * Bg: Backend updating the global state and emitting the procsignalbarrier
133 : : * Bd: Backends in "off" state
134 : : * Be: Backends in "on" state
135 : : * Bo: Backends in "inprogress-off" state
136 : : * Bi: Backends in "inprogress-on" state
137 : : *
138 : : * Backends transition from the Be state to Bd like so: Be -> Bo -> Bd. From
139 : : * all other states, the transition can be straight to Bd.
140 : : *
141 : : * The goal is to transition all backends to Bd making the others empty sets.
142 : : * Backends in Bo write data checksums, but don't validate them, such that
143 : : * backends still in Be can continue to validate pages until the barrier has
144 : : * been absorbed such that they are in Bo. Once all backends are in Bo, the
145 : : * barrier to transition to "off" can be raised and all backends can safely
146 : : * stop writing data checksums as no backend is enforcing data checksum
147 : : * validation any longer.
148 : : *
149 : : * 4. Future opportunities for optimizations
150 : : * -----------------------------------------
151 : : * Below are some potential optimizations and improvements which were brought
152 : : * up during reviews of this feature, but which weren't implemented in the
153 : : * initial version. These are ideas listed without any validation on their
154 : : * feasibility or potential payoff. More discussion on (most of) these can be
155 : : * found on the -hackers threads linked to in the commit message of this
156 : : * feature.
157 : : *
158 : : * * Launching datachecksumsworker for resuming operation from the startup
159 : : * process: Currently users have to restart processing manually after a
160 : : * restart since dynamic background worker cannot be started from the
161 : : * postmaster. Changing the startup process could make restarting the
162 : : * processing automatic on cluster restart.
163 : : * * Avoid dirtying the page when checksums already match: Iff the checksum
164 : : * on the page happens to already match we still dirty the page. It should
165 : : * be enough to only do the log_newpage_buffer() call in that case.
166 : : * * Teach pg_checksums to avoid checksummed pages when pg_checksums is used
167 : : * to enable checksums on a cluster which is in inprogress-on state and
168 : : * may have checksummed pages (make pg_checksums be able to resume an
169 : : * online operation). This should only be attempted for wal_level minimal.
170 : : * * Restartability (not necessarily with page granularity).
171 : : * * Avoid processing databases which were created during inprogress-on.
172 : : * Right now all databases are processed regardless to be safe.
173 : : * * Teach CREATE DATABASE to calculate checksums for databases created
174 : : * during inprogress-on with a template database which has yet to be
175 : : * processed.
176 : : *
177 : : *
178 : : * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group
179 : : * Portions Copyright (c) 1994, Regents of the University of California
180 : : *
181 : : *
182 : : * IDENTIFICATION
183 : : * src/backend/postmaster/datachecksum_state.c
184 : : *
185 : : *-------------------------------------------------------------------------
186 : : */
187 : : #include "postgres.h"
188 : :
189 : : #include "access/genam.h"
190 : : #include "access/heapam.h"
191 : : #include "access/htup_details.h"
192 : : #include "access/xact.h"
193 : : #include "access/xlog.h"
194 : : #include "access/xloginsert.h"
195 : : #include "catalog/indexing.h"
196 : : #include "catalog/pg_class.h"
197 : : #include "catalog/pg_database.h"
198 : : #include "commands/progress.h"
199 : : #include "commands/vacuum.h"
200 : : #include "common/relpath.h"
201 : : #include "miscadmin.h"
202 : : #include "pgstat.h"
203 : : #include "postmaster/bgworker.h"
204 : : #include "postmaster/bgwriter.h"
205 : : #include "postmaster/datachecksum_state.h"
206 : : #include "storage/bufmgr.h"
207 : : #include "storage/checksum.h"
208 : : #include "storage/ipc.h"
209 : : #include "storage/latch.h"
210 : : #include "storage/lmgr.h"
211 : : #include "storage/lwlock.h"
212 : : #include "storage/procarray.h"
213 : : #include "storage/smgr.h"
214 : : #include "storage/subsystems.h"
215 : : #include "tcop/tcopprot.h"
216 : : #include "utils/builtins.h"
217 : : #include "utils/fmgroids.h"
218 : : #include "utils/injection_point.h"
219 : : #include "utils/lsyscache.h"
220 : : #include "utils/ps_status.h"
221 : : #include "utils/syscache.h"
222 : : #include "utils/wait_event.h"
223 : :
224 : : /*
225 : : * Configuration of conditions which must match when absorbing a procsignal
226 : : * barrier during data checksum enable/disable operations. A single function
227 : : * is used for absorbing all barriers, and the current and target states must
228 : : * be defined as a from/to tuple in the checksum_barriers struct.
229 : : */
230 : : typedef struct ChecksumBarrierCondition
231 : : {
232 : : /* Current state of data checksums */
233 : : int from;
234 : : /* Target state for data checksums */
235 : : int to;
236 : : } ChecksumBarrierCondition;
237 : :
238 : : static const ChecksumBarrierCondition checksum_barriers[9] =
239 : : {
240 : : /*
241 : : * Disabling checksums: If checksums are currently enabled, disabling must
242 : : * go through the 'inprogress-off' state.
243 : : */
244 : : {PG_DATA_CHECKSUM_VERSION, PG_DATA_CHECKSUM_INPROGRESS_OFF},
245 : : {PG_DATA_CHECKSUM_INPROGRESS_OFF, PG_DATA_CHECKSUM_OFF},
246 : :
247 : : /*
248 : : * If checksums are in the process of being enabled, but are not yet being
249 : : * verified, we can abort by going back to 'off' state.
250 : : */
251 : : {PG_DATA_CHECKSUM_INPROGRESS_ON, PG_DATA_CHECKSUM_OFF},
252 : :
253 : : /*
254 : : * Enabling checksums must normally go through the 'inprogress-on' state.
255 : : */
256 : : {PG_DATA_CHECKSUM_OFF, PG_DATA_CHECKSUM_INPROGRESS_ON},
257 : : {PG_DATA_CHECKSUM_INPROGRESS_ON, PG_DATA_CHECKSUM_VERSION},
258 : :
259 : : /*
260 : : * If checksums are being disabled but all backends are still computing
261 : : * checksums, we can go straight back to 'on'
262 : : */
263 : : {PG_DATA_CHECKSUM_INPROGRESS_OFF, PG_DATA_CHECKSUM_VERSION},
264 : :
265 : : /*
266 : : * If checksums are being enabled when launcher_exit is executed, state is
267 : : * set to off since we cannot reach on at that point.
268 : : */
269 : : {PG_DATA_CHECKSUM_INPROGRESS_ON, PG_DATA_CHECKSUM_INPROGRESS_OFF},
270 : :
271 : : /*
272 : : * Transitions that can happen when a new request is made while another is
273 : : * currently being processed.
274 : : */
275 : : {PG_DATA_CHECKSUM_INPROGRESS_OFF, PG_DATA_CHECKSUM_INPROGRESS_ON},
276 : : {PG_DATA_CHECKSUM_OFF, PG_DATA_CHECKSUM_INPROGRESS_OFF},
277 : : };
278 : :
279 : : /*
280 : : * Signaling between backends calling pg_enable/disable_data_checksums, the
281 : : * checksums launcher process, and the checksums worker process.
282 : : *
283 : : * This struct is protected by DataChecksumsWorkerLock
284 : : */
285 : : typedef struct DataChecksumsStateStruct
286 : : {
287 : : /*
288 : : * These are set by pg_{enable|disable}_data_checksums, to tell the
289 : : * launcher what the target state is.
290 : : */
291 : : DataChecksumsWorkerOperation launch_operation;
292 : : int launch_cost_delay;
293 : : int launch_cost_limit;
294 : :
295 : : /*
296 : : * Is a launcher process currently running? This is set by the main
297 : : * launcher process, after it has read the above launch_* parameters.
298 : : */
299 : : bool launcher_running;
300 : :
301 : : /*
302 : : * Is a worker process currently running? This is set by the worker
303 : : * launcher when it starts waiting for a worker process to finish.
304 : : */
305 : : int worker_pid;
306 : :
307 : : /*
308 : : * These fields indicate the target state that the launcher is currently
309 : : * working towards. They can be different from the corresponding launch_*
310 : : * fields, if a new pg_enable/disable_data_checksums() call was made while
311 : : * the launcher/worker was already running.
312 : : *
313 : : * The below members are set when the launcher starts, and are only
314 : : * accessed read-only by the single worker. Thus, we can access these
315 : : * without a lock. If multiple workers, or dynamic cost parameters, are
316 : : * supported at some point then this would need to be revisited.
317 : : */
318 : : DataChecksumsWorkerOperation operation;
319 : : int cost_delay;
320 : : int cost_limit;
321 : :
322 : : /*
323 : : * Signaling between the launcher and the worker process.
324 : : *
325 : : * As there is only a single worker, and the launcher won't read these
326 : : * until the worker exits, they can be accessed without the need for a
327 : : * lock. If multiple workers are supported then this will have to be
328 : : * revisited.
329 : : */
330 : :
331 : : /* result, set by worker before exiting */
332 : : DataChecksumsWorkerResult success;
333 : :
334 : : /*
335 : : * Tells the worker process whether it should also process the shared
336 : : * catalogs
337 : : */
338 : : bool process_shared_catalogs;
339 : : } DataChecksumsStateStruct;
340 : :
341 : : /* Shared memory segment for datachecksumsworker */
342 : : static DataChecksumsStateStruct *DataChecksumState;
343 : :
344 : : typedef struct DataChecksumsWorkerDatabase
345 : : {
346 : : Oid dboid;
347 : : char *dbname;
348 : : } DataChecksumsWorkerDatabase;
349 : :
350 : : /* Flag set by the interrupt handler */
351 : : static volatile sig_atomic_t abort_requested = false;
352 : :
353 : : /*
354 : : * Have we set the DataChecksumsStateStruct->launcher_running flag?
355 : : * If we have, we need to clear it before exiting!
356 : : */
357 : : static volatile sig_atomic_t launcher_running = false;
358 : :
359 : : /* Are we enabling data checksums, or disabling them? */
360 : : static DataChecksumsWorkerOperation operation;
361 : :
362 : : /* Prototypes */
363 : : static void DataChecksumsShmemRequest(void *arg);
364 : : static bool DatabaseExists(Oid dboid);
365 : : static List *BuildDatabaseList(void);
366 : : static List *BuildRelationList(bool temp_relations, bool include_shared);
367 : : static void FreeDatabaseList(List *dblist);
368 : : static DataChecksumsWorkerResult ProcessDatabase(DataChecksumsWorkerDatabase *db);
369 : : static bool ProcessAllDatabases(void);
370 : : static bool ProcessSingleRelationFork(Relation reln, ForkNumber forkNum, BufferAccessStrategy strategy);
371 : : static void launcher_cancel_handler(SIGNAL_ARGS);
372 : : static void WaitForAllTransactionsToFinish(void);
373 : :
374 : : const ShmemCallbacks DataChecksumsShmemCallbacks = {
375 : : .request_fn = DataChecksumsShmemRequest,
376 : : };
377 : :
378 : : #define CHECK_FOR_ABORT_REQUEST() \
379 : : do { \
380 : : LWLockAcquire(DataChecksumsWorkerLock, LW_SHARED); \
381 : : if (DataChecksumState->launch_operation != operation) \
382 : : abort_requested = true; \
383 : : LWLockRelease(DataChecksumsWorkerLock); \
384 : : } while (0)
385 : :
386 : :
387 : : /*****************************************************************************
388 : : * Functionality for manipulating the data checksum state in the cluster
389 : : */
390 : :
391 : : void
32 dgustafsson@postgres 392 :GNC 4 : EmitAndWaitDataChecksumsBarrier(uint32 state)
393 : : {
394 : : uint64 barrier;
395 : :
396 [ + + + + : 4 : switch (state)
- ]
397 : : {
398 : 1 : case PG_DATA_CHECKSUM_INPROGRESS_ON:
399 : 1 : barrier = EmitProcSignalBarrier(PROCSIGNAL_BARRIER_CHECKSUM_INPROGRESS_ON);
400 : 1 : WaitForProcSignalBarrier(barrier);
401 : 1 : break;
402 : :
403 : 1 : case PG_DATA_CHECKSUM_INPROGRESS_OFF:
404 : 1 : barrier = EmitProcSignalBarrier(PROCSIGNAL_BARRIER_CHECKSUM_INPROGRESS_OFF);
405 : 1 : WaitForProcSignalBarrier(barrier);
406 : 1 : break;
407 : :
408 : 1 : case PG_DATA_CHECKSUM_VERSION:
409 : 1 : barrier = EmitProcSignalBarrier(PROCSIGNAL_BARRIER_CHECKSUM_ON);
410 : 1 : WaitForProcSignalBarrier(barrier);
411 : 1 : break;
412 : :
413 : 1 : case PG_DATA_CHECKSUM_OFF:
414 : 1 : barrier = EmitProcSignalBarrier(PROCSIGNAL_BARRIER_CHECKSUM_OFF);
415 : 1 : WaitForProcSignalBarrier(barrier);
416 : 1 : break;
417 : :
32 dgustafsson@postgres 418 :UNC 0 : default:
419 : 0 : Assert(false);
420 : : }
32 dgustafsson@postgres 421 :GNC 4 : }
422 : :
423 : : /*
424 : : * AbsorbDataChecksumsBarrier
425 : : * Generic function for absorbing data checksum state changes
426 : : *
427 : : * All procsignalbarriers regarding data checksum state changes are absorbed
428 : : * with this function. The set of conditions required for the state change to
429 : : * be accepted are listed in the checksum_barriers struct, target_state is
430 : : * used to look up the relevant entry.
431 : : */
432 : : bool
433 : 230 : AbsorbDataChecksumsBarrier(ProcSignalBarrierType barrier)
434 : : {
435 : : uint32 target_state;
436 : 230 : int current = data_checksums;
437 : 230 : bool found = false;
438 : :
439 : : /*
440 : : * Translate the barrier condition to the target state, doing it here
441 : : * instead of in the procsignal code saves the latter from knowing about
442 : : * checksum states.
443 : : */
444 [ + + + + : 230 : switch (barrier)
- ]
445 : : {
446 : 72 : case PROCSIGNAL_BARRIER_CHECKSUM_INPROGRESS_ON:
447 : 72 : target_state = PG_DATA_CHECKSUM_INPROGRESS_ON;
448 : 72 : break;
449 : 56 : case PROCSIGNAL_BARRIER_CHECKSUM_ON:
450 : 56 : target_state = PG_DATA_CHECKSUM_VERSION;
451 : 56 : break;
452 : 52 : case PROCSIGNAL_BARRIER_CHECKSUM_INPROGRESS_OFF:
453 : 52 : target_state = PG_DATA_CHECKSUM_INPROGRESS_OFF;
454 : 52 : break;
455 : 50 : case PROCSIGNAL_BARRIER_CHECKSUM_OFF:
456 : 50 : target_state = PG_DATA_CHECKSUM_OFF;
457 : 50 : break;
32 dgustafsson@postgres 458 :UNC 0 : default:
459 [ # # ]: 0 : elog(ERROR, "incorrect barrier \"%i\" received", barrier);
460 : : }
461 : :
462 : : /*
463 : : * If the target state matches the current state then the barrier has been
464 : : * repeated.
465 : : */
32 dgustafsson@postgres 466 [ - + ]:GNC 230 : if (current == target_state)
32 dgustafsson@postgres 467 :UNC 0 : return true;
468 : :
469 : : /*
470 : : * If the cluster is in recovery we skip the validation of current state
471 : : * since the replay is trusted.
472 : : */
32 dgustafsson@postgres 473 [ + + ]:GNC 230 : if (RecoveryInProgress())
474 : : {
475 : 24 : SetLocalDataChecksumState(target_state);
476 : 24 : return true;
477 : : }
478 : :
479 : : /*
480 : : * Find the barrier condition definition for the target state. Not finding
481 : : * a condition would be a grave programmer error as the states are a
482 : : * discrete set.
483 : : */
484 [ + - + + ]: 932 : for (int i = 0; i < lengthof(checksum_barriers) && !found; i++)
485 : : {
486 [ + + + + ]: 726 : if (checksum_barriers[i].from == current && checksum_barriers[i].to == target_state)
487 : 206 : found = true;
488 : : }
489 : :
490 : : /*
491 : : * If the relevant state criteria aren't satisfied, throw an error which
492 : : * will be caught by the procsignal machinery for a later retry.
493 : : */
494 [ - + ]: 206 : if (!found)
32 dgustafsson@postgres 495 [ # # ]:UNC 0 : ereport(ERROR,
496 : : errcode(ERRCODE_INVALID_PARAMETER_VALUE),
497 : : errmsg("incorrect data checksum state %i for target state %i",
498 : : current, target_state));
499 : :
32 dgustafsson@postgres 500 :GNC 206 : SetLocalDataChecksumState(target_state);
501 : 206 : return true;
502 : : }
503 : :
504 : :
505 : : /*
506 : : * Disables data checksums for the cluster, if applicable. Starts a background
507 : : * worker which turns off the data checksums.
508 : : */
509 : : Datum
510 : 6 : disable_data_checksums(PG_FUNCTION_ARGS)
511 : : {
5 512 : 6 : PreventCommandDuringRecovery("pg_disable_data_checksums()");
513 : :
32 514 [ - + ]: 6 : if (!superuser())
32 dgustafsson@postgres 515 [ # # ]:UNC 0 : ereport(ERROR,
516 : : errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
517 : : errmsg("must be superuser to change data checksum state"));
518 : :
32 dgustafsson@postgres 519 :GNC 6 : StartDataChecksumsWorkerLauncher(DISABLE_DATACHECKSUMS, 0, 0);
520 : 6 : PG_RETURN_VOID();
521 : : }
522 : :
523 : : /*
524 : : * Enables data checksums for the cluster, if applicable. Supports vacuum-
525 : : * like cost based throttling to limit system load. Starts a background worker
526 : : * which updates data checksums on existing data.
527 : : */
528 : : Datum
529 : 9 : enable_data_checksums(PG_FUNCTION_ARGS)
530 : : {
531 : 9 : int cost_delay = PG_GETARG_INT32(0);
532 : 9 : int cost_limit = PG_GETARG_INT32(1);
533 : :
5 534 : 9 : PreventCommandDuringRecovery("pg_enable_data_checksums()");
535 : :
32 536 [ - + ]: 9 : if (!superuser())
32 dgustafsson@postgres 537 [ # # ]:UNC 0 : ereport(ERROR,
538 : : errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
539 : : errmsg("must be superuser to change data checksum state"));
540 : :
32 dgustafsson@postgres 541 [ - + ]:GNC 9 : if (cost_delay < 0)
32 dgustafsson@postgres 542 [ # # ]:UNC 0 : ereport(ERROR,
543 : : errcode(ERRCODE_INVALID_PARAMETER_VALUE),
544 : : errmsg("cost delay cannot be a negative value"));
545 : :
32 dgustafsson@postgres 546 [ - + ]:GNC 9 : if (cost_limit <= 0)
32 dgustafsson@postgres 547 [ # # ]:UNC 0 : ereport(ERROR,
548 : : errcode(ERRCODE_INVALID_PARAMETER_VALUE),
549 : : errmsg("cost limit must be greater than zero"));
550 : :
32 dgustafsson@postgres 551 :GNC 9 : StartDataChecksumsWorkerLauncher(ENABLE_DATACHECKSUMS, cost_delay, cost_limit);
552 : :
553 : 9 : PG_RETURN_VOID();
554 : : }
555 : :
556 : :
557 : : /*****************************************************************************
558 : : * Functionality for running the datachecksumsworker and associated launcher
559 : : */
560 : :
561 : : /*
562 : : * StartDataChecksumsWorkerLauncher
563 : : * Main entry point for datachecksumsworker launcher process
564 : : *
565 : : * The main entrypoint for starting data checksums processing for enabling as
566 : : * well as disabling.
567 : : */
568 : : void
569 : 15 : StartDataChecksumsWorkerLauncher(DataChecksumsWorkerOperation op,
570 : : int cost_delay,
571 : : int cost_limit)
572 : : {
573 : : BackgroundWorker bgw;
574 : : BackgroundWorkerHandle *bgw_handle;
575 : : bool running;
576 : :
577 : : #ifdef USE_ASSERT_CHECKING
578 : : /* The cost delay settings have no effect when disabling */
579 [ + + ]: 15 : if (op == DISABLE_DATACHECKSUMS)
580 [ + - - + ]: 6 : Assert(cost_delay == 0 && cost_limit == 0);
581 : : #endif
582 : :
583 : 15 : INJECTION_POINT("datachecksumsworker-startup-delay", NULL);
584 : :
585 : : /* Store the desired state in shared memory */
586 : 15 : LWLockAcquire(DataChecksumsWorkerLock, LW_EXCLUSIVE);
587 : :
588 : 15 : DataChecksumState->launch_operation = op;
589 : 15 : DataChecksumState->launch_cost_delay = cost_delay;
590 : 15 : DataChecksumState->launch_cost_limit = cost_limit;
591 : :
592 : : /* Is the launcher already running? If so, what is it doing? */
12 drowley@postgresql.o 593 : 15 : running = DataChecksumState->launcher_running;
594 : :
32 dgustafsson@postgres 595 : 15 : LWLockRelease(DataChecksumsWorkerLock);
596 : :
597 : : /*
598 : : * Launch a new launcher process, if it's not running already.
599 : : *
600 : : * If the launcher is currently busy enabling the checksums, and we want
601 : : * them disabled (or vice versa), the launcher will notice that at latest
602 : : * when it's about to exit, and will loop back process the new request. So
603 : : * if the launcher is already running, we don't need to do anything more
604 : : * here to abort it.
605 : : *
606 : : * If you call pg_enable/disable_data_checksums() twice in a row, before
607 : : * the launcher has had a chance to start up, we still end up launching it
608 : : * twice. That's OK, the second invocation will see that a launcher is
609 : : * already running and exit quickly.
610 : : */
12 drowley@postgresql.o 611 [ + - ]: 15 : if (!running)
612 : : {
5 dgustafsson@postgres 613 [ + + + + : 15 : if ((op == ENABLE_DATACHECKSUMS && DataChecksumsOn()) ||
+ + ]
614 [ + + ]: 6 : (op == DISABLE_DATACHECKSUMS && DataChecksumsOff()))
615 : : {
616 [ + - ]: 3 : ereport(LOG,
617 : : errmsg("data checksums already in desired state, exiting"));
618 : 3 : return;
619 : : }
620 : :
621 : : /*
622 : : * Prepare the BackgroundWorker and launch it.
623 : : */
32 624 : 12 : memset(&bgw, 0, sizeof(bgw));
625 : 12 : bgw.bgw_flags = BGWORKER_SHMEM_ACCESS | BGWORKER_BACKEND_DATABASE_CONNECTION;
626 : 12 : bgw.bgw_start_time = BgWorkerStart_RecoveryFinished;
627 : 12 : snprintf(bgw.bgw_library_name, BGW_MAXLEN, "postgres");
628 : 12 : snprintf(bgw.bgw_function_name, BGW_MAXLEN, "DataChecksumsWorkerLauncherMain");
629 : 12 : snprintf(bgw.bgw_name, BGW_MAXLEN, "datachecksum launcher");
630 : 12 : snprintf(bgw.bgw_type, BGW_MAXLEN, "datachecksum launcher");
631 : 12 : bgw.bgw_restart_time = BGW_NEVER_RESTART;
632 : 12 : bgw.bgw_notify_pid = MyProcPid;
633 : 12 : bgw.bgw_main_arg = (Datum) 0;
634 : :
635 [ - + ]: 12 : if (!RegisterDynamicBackgroundWorker(&bgw, &bgw_handle))
32 dgustafsson@postgres 636 [ # # ]:UNC 0 : ereport(ERROR,
637 : : errcode(ERRCODE_INSUFFICIENT_RESOURCES),
638 : : errmsg("failed to start background worker to process data checksums"));
639 : : }
640 : : else
641 : : {
5 642 [ # # ]: 0 : ereport(LOG,
643 : : errmsg("data checksum processing already running"));
644 : : }
645 : : }
646 : :
647 : : /*
648 : : * ProcessSingleRelationFork
649 : : * Enable data checksums in a single relation/fork.
650 : : *
651 : : * Returns true if successful, and false if *aborted*. On error, an actual
652 : : * error is raised in the lower levels.
653 : : */
654 : : static bool
32 dgustafsson@postgres 655 :GNC 6471 : ProcessSingleRelationFork(Relation reln, ForkNumber forkNum, BufferAccessStrategy strategy)
656 : : {
657 : 6471 : BlockNumber numblocks = RelationGetNumberOfBlocksInFork(reln, forkNum);
658 : : char activity[NAMEDATALEN * 2 + 128];
659 : : char *relns;
660 : :
661 : 6471 : relns = get_namespace_name(RelationGetNamespace(reln));
662 : :
663 : : /* Report the current relation to pg_stat_activity */
664 : 6471 : snprintf(activity, sizeof(activity) - 1, "processing: %s.%s (%s, %u blocks)",
665 [ + - ]: 6471 : (relns ? relns : ""), RelationGetRelationName(reln), forkNames[forkNum], numblocks);
666 : 6471 : pgstat_report_activity(STATE_RUNNING, activity);
667 : 6471 : pgstat_progress_update_param(PROGRESS_DATACHECKSUMS_BLOCKS_TOTAL, numblocks);
668 [ + - ]: 6471 : if (relns)
669 : 6471 : pfree(relns);
670 : :
671 : : /*
672 : : * We are looping over the blocks which existed at the time of process
673 : : * start, which is safe since new blocks are created with checksums set
674 : : * already due to the state being "inprogress-on".
675 : : */
676 [ + + ]: 43801 : for (BlockNumber blknum = 0; blknum < numblocks; blknum++)
677 : : {
678 : 37330 : Buffer buf = ReadBufferExtended(reln, forkNum, blknum, RBM_NORMAL, strategy);
679 : :
680 : : /* Need to get an exclusive lock to mark the buffer as dirty */
681 : 37330 : LockBuffer(buf, BUFFER_LOCK_EXCLUSIVE);
682 : :
683 : : /*
684 : : * Mark the buffer as dirty and force a full page write. We have to
685 : : * re-write the page to WAL even if the checksum hasn't changed,
686 : : * because if there is a replica it might have a slightly different
687 : : * version of the page with an invalid checksum, caused by unlogged
688 : : * changes (e.g. hint bits) on the primary happening while checksums
689 : : * were off. This can happen if there was a valid checksum on the page
690 : : * at one point in the past, so only when checksums are first on, then
691 : : * off, and then turned on again. TODO: investigate if this could be
692 : : * avoided if the checksum is calculated to be correct and wal_level
693 : : * is set to "minimal",
694 : : */
695 : 37330 : START_CRIT_SECTION();
696 : 37330 : MarkBufferDirty(buf);
697 : 37330 : log_newpage_buffer(buf, false);
698 [ - + ]: 37330 : END_CRIT_SECTION();
699 : :
700 : 37330 : UnlockReleaseBuffer(buf);
701 : :
702 : : /*
703 : : * This is the only place where we check if we are asked to abort, the
704 : : * abortion will bubble up from here.
705 : : */
706 [ - + ]: 37330 : Assert(operation == ENABLE_DATACHECKSUMS);
707 : 37330 : LWLockAcquire(DataChecksumsWorkerLock, LW_SHARED);
708 [ - + ]: 37330 : if (DataChecksumState->launch_operation == DISABLE_DATACHECKSUMS)
32 dgustafsson@postgres 709 :UNC 0 : abort_requested = true;
32 dgustafsson@postgres 710 :GNC 37330 : LWLockRelease(DataChecksumsWorkerLock);
711 : :
712 [ - + ]: 37330 : if (abort_requested)
32 dgustafsson@postgres 713 :UNC 0 : return false;
714 : :
715 : : /* update the block counter */
32 dgustafsson@postgres 716 :GNC 37330 : pgstat_progress_update_param(PROGRESS_DATACHECKSUMS_BLOCKS_DONE,
717 : 37330 : (blknum + 1));
718 : :
719 : : /*
720 : : * Processing is re-using the vacuum cost delay for process
721 : : * throttling, hence why we call vacuum APIs here.
722 : : */
723 : 37330 : vacuum_delay_point(false);
724 : : }
725 : :
726 : 6471 : return true;
727 : : }
728 : :
729 : : /*
730 : : * ProcessSingleRelationByOid
731 : : * Process a single relation based on oid.
732 : : *
733 : : * Returns true if successful, and false if *aborted*. On error, an actual
734 : : * error is raised in the lower levels.
735 : : */
736 : : static bool
737 : 4982 : ProcessSingleRelationByOid(Oid relationId, BufferAccessStrategy strategy)
738 : : {
739 : : Relation rel;
740 : 4982 : bool aborted = false;
741 : :
742 : 4982 : StartTransactionCommand();
743 : :
744 : 4982 : rel = try_relation_open(relationId, AccessShareLock);
745 [ - + ]: 4982 : if (rel == NULL)
746 : : {
747 : : /*
748 : : * Relation no longer exists. We don't consider this an error since
749 : : * there are no pages in it that need data checksums, and thus return
750 : : * true. The worker operates off a list of relations generated at the
751 : : * start of processing, so relations being dropped in the meantime is
752 : : * to be expected.
753 : : */
32 dgustafsson@postgres 754 :UNC 0 : CommitTransactionCommand();
755 : 0 : pgstat_report_activity(STATE_IDLE, NULL);
756 : 0 : return true;
757 : : }
32 dgustafsson@postgres 758 :GNC 4982 : RelationGetSmgr(rel);
759 : :
760 [ + + ]: 24910 : for (ForkNumber fnum = 0; fnum <= MAX_FORKNUM; fnum++)
761 : : {
762 [ + + ]: 19928 : if (smgrexists(rel->rd_smgr, fnum))
763 : : {
764 [ - + ]: 6471 : if (!ProcessSingleRelationFork(rel, fnum, strategy))
765 : : {
32 dgustafsson@postgres 766 :UNC 0 : aborted = true;
767 : 0 : break;
768 : : }
769 : : }
770 : : }
32 dgustafsson@postgres 771 :GNC 4982 : relation_close(rel, AccessShareLock);
772 : :
773 : 4982 : CommitTransactionCommand();
774 : 4982 : pgstat_report_activity(STATE_IDLE, NULL);
775 : :
776 : 4982 : return !aborted;
777 : : }
778 : :
779 : : /*
780 : : * ProcessDatabase
781 : : * Enable data checksums in a single database.
782 : : *
783 : : * We do this by launching a dynamic background worker into this database, and
784 : : * waiting for it to finish. We have to do this in a separate worker, since
785 : : * each process can only be connected to one database during its lifetime.
786 : : */
787 : : static DataChecksumsWorkerResult
788 : 20 : ProcessDatabase(DataChecksumsWorkerDatabase *db)
789 : : {
790 : : BackgroundWorker bgw;
791 : : BackgroundWorkerHandle *bgw_handle;
792 : : BgwHandleStatus status;
793 : : pid_t pid;
794 : : char activity[NAMEDATALEN + 64];
795 : :
5 796 : 20 : LWLockAcquire(DataChecksumsWorkerLock, LW_EXCLUSIVE);
32 797 : 20 : DataChecksumState->success = DATACHECKSUMSWORKER_FAILED;
5 798 : 20 : LWLockRelease(DataChecksumsWorkerLock);
799 : :
32 800 : 20 : memset(&bgw, 0, sizeof(bgw));
801 : 20 : bgw.bgw_flags = BGWORKER_SHMEM_ACCESS | BGWORKER_BACKEND_DATABASE_CONNECTION;
802 : 20 : bgw.bgw_start_time = BgWorkerStart_RecoveryFinished;
803 : 20 : snprintf(bgw.bgw_library_name, BGW_MAXLEN, "postgres");
804 : 20 : snprintf(bgw.bgw_function_name, BGW_MAXLEN, "%s", "DataChecksumsWorkerMain");
805 : 20 : snprintf(bgw.bgw_name, BGW_MAXLEN, "datachecksum worker");
806 : 20 : snprintf(bgw.bgw_type, BGW_MAXLEN, "datachecksum worker");
807 : 20 : bgw.bgw_restart_time = BGW_NEVER_RESTART;
808 : 20 : bgw.bgw_notify_pid = MyProcPid;
809 : 20 : bgw.bgw_main_arg = ObjectIdGetDatum(db->dboid);
810 : :
811 : : /*
812 : : * If there are no worker slots available, there is little we can do. If
813 : : * we retry in a bit it's still unlikely that the user has managed to
814 : : * reconfigure in the meantime and we'd be run through retries fast.
815 : : */
816 [ - + ]: 20 : if (!RegisterDynamicBackgroundWorker(&bgw, &bgw_handle))
817 : : {
32 dgustafsson@postgres 818 [ # # ]:UNC 0 : ereport(WARNING,
819 : : errmsg("could not start background worker for enabling data checksums in database \"%s\"",
820 : : db->dbname),
821 : : errhint("The \"%s\" setting might be too low.", "max_worker_processes"));
822 : 0 : return DATACHECKSUMSWORKER_FAILED;
823 : : }
824 : :
32 dgustafsson@postgres 825 :GNC 20 : status = WaitForBackgroundWorkerStartup(bgw_handle, &pid);
826 [ - + ]: 20 : if (status == BGWH_STOPPED)
827 : : {
828 : : /*
829 : : * If the worker managed to start, and stop, before we got to waiting
830 : : * for it we can see a STOPPED status here without it being a failure.
831 : : */
5 dgustafsson@postgres 832 :UNC 0 : LWLockAcquire(DataChecksumsWorkerLock, LW_SHARED);
29 833 [ # # ]: 0 : if (DataChecksumState->success == DATACHECKSUMSWORKER_SUCCESSFUL)
834 : : {
5 835 : 0 : LWLockRelease(DataChecksumsWorkerLock);
29 836 : 0 : pgstat_report_activity(STATE_IDLE, NULL);
837 : 0 : LWLockAcquire(DataChecksumsWorkerLock, LW_EXCLUSIVE);
838 : 0 : DataChecksumState->worker_pid = InvalidPid;
839 : 0 : LWLockRelease(DataChecksumsWorkerLock);
840 : 0 : return DataChecksumState->success;
841 : : }
5 842 : 0 : LWLockRelease(DataChecksumsWorkerLock);
843 : :
32 844 [ # # ]: 0 : ereport(WARNING,
845 : : errmsg("could not start background worker for enabling data checksums in database \"%s\"",
846 : : db->dbname),
847 : : errhint("More details on the error might be found in the server log."));
848 : :
849 : : /*
850 : : * Heuristic to see if the database was dropped, and if it was we can
851 : : * treat it as not an error, else treat as fatal and error out.
852 : : */
853 [ # # ]: 0 : if (DatabaseExists(db->dboid))
854 : 0 : return DATACHECKSUMSWORKER_FAILED;
855 : : else
856 : 0 : return DATACHECKSUMSWORKER_DROPDB;
857 : : }
858 : :
859 : : /*
860 : : * If the postmaster crashed we cannot end up with a processed database so
861 : : * we have no alternative other than exiting. When enabling checksums we
862 : : * won't at this time have changed the data checksums state in pg_control
863 : : * to enabled so when the cluster comes back up processing will have to be
864 : : * restarted.
865 : : */
32 dgustafsson@postgres 866 [ - + ]:GNC 20 : if (status == BGWH_POSTMASTER_DIED)
32 dgustafsson@postgres 867 [ # # ]:UNC 0 : ereport(FATAL,
868 : : errcode(ERRCODE_ADMIN_SHUTDOWN),
869 : : errmsg("cannot enable data checksums without the postmaster process"),
870 : : errhint("Restart the database and restart data checksum processing by calling pg_enable_data_checksums()."));
871 : :
32 dgustafsson@postgres 872 [ - + ]:GNC 20 : Assert(status == BGWH_STARTED);
873 [ + - ]: 20 : ereport(LOG,
874 : : errmsg("initiating data checksum processing in database \"%s\"",
875 : : db->dbname));
876 : :
877 : : /* Save the pid of the worker so we can signal it later */
878 : 20 : LWLockAcquire(DataChecksumsWorkerLock, LW_EXCLUSIVE);
879 : 20 : DataChecksumState->worker_pid = pid;
880 : 20 : LWLockRelease(DataChecksumsWorkerLock);
881 : :
882 : 20 : snprintf(activity, sizeof(activity) - 1,
883 : : "Waiting for worker in database %s (pid %ld)", db->dbname, (long) pid);
884 : 20 : pgstat_report_activity(STATE_RUNNING, activity);
885 : :
886 : 20 : status = WaitForBackgroundWorkerShutdown(bgw_handle);
887 [ - + ]: 19 : if (status == BGWH_POSTMASTER_DIED)
32 dgustafsson@postgres 888 [ # # ]:UNC 0 : ereport(FATAL,
889 : : errcode(ERRCODE_ADMIN_SHUTDOWN),
890 : : errmsg("postmaster exited during data checksum processing in \"%s\"",
891 : : db->dbname),
892 : : errhint("Restart the database and restart data checksum processing by calling pg_enable_data_checksums()."));
893 : :
5 dgustafsson@postgres 894 :GNC 19 : LWLockAcquire(DataChecksumsWorkerLock, LW_SHARED);
32 895 [ - + ]: 19 : if (DataChecksumState->success == DATACHECKSUMSWORKER_ABORTED)
32 dgustafsson@postgres 896 [ # # ]:UNC 0 : ereport(LOG,
897 : : errmsg("data checksums processing was aborted in database \"%s\"",
898 : : db->dbname));
5 dgustafsson@postgres 899 :GNC 19 : LWLockRelease(DataChecksumsWorkerLock);
900 : :
32 901 : 19 : pgstat_report_activity(STATE_IDLE, NULL);
902 : 19 : LWLockAcquire(DataChecksumsWorkerLock, LW_EXCLUSIVE);
903 : 19 : DataChecksumState->worker_pid = InvalidPid;
904 : 19 : LWLockRelease(DataChecksumsWorkerLock);
905 : :
906 : 19 : return DataChecksumState->success;
907 : : }
908 : :
909 : : /*
910 : : * launcher_exit
911 : : *
912 : : * Internal routine for cleaning up state when a launcher process which has
913 : : * performed checksum operations exits. A launcher process which is exiting due
914 : : * to a duplicate started launcher does not need to perform any cleanup and
915 : : * this function should not be called. Otherwise, we need to clean up the abort
916 : : * flag to ensure that processing started again if it was previously aborted
917 : : * (note: started again, *not* restarted from where it left off).
918 : : */
919 : : static void
920 : 12 : launcher_exit(int code, Datum arg)
921 : : {
922 : 12 : abort_requested = false;
923 : :
924 [ + + ]: 12 : if (launcher_running)
925 : : {
926 : 2 : LWLockAcquire(DataChecksumsWorkerLock, LW_EXCLUSIVE);
927 [ + + ]: 2 : if (DataChecksumState->worker_pid != InvalidPid)
928 : : {
929 [ + - ]: 1 : ereport(LOG,
930 : : errmsg("data checksums launcher exiting while worker is still running, signalling worker"));
931 : 1 : kill(DataChecksumState->worker_pid, SIGTERM);
932 : : }
933 : 2 : LWLockRelease(DataChecksumsWorkerLock);
934 : : }
935 : :
936 : : /*
937 : : * If the launcher is exiting before data checksums are enabled then set
938 : : * the state to off since processing cannot be resumed.
939 : : */
940 [ + + ]: 12 : if (DataChecksumsInProgressOn())
941 : 1 : SetDataChecksumsOff();
942 : :
943 : 12 : LWLockAcquire(DataChecksumsWorkerLock, LW_EXCLUSIVE);
944 : 12 : launcher_running = false;
945 : 12 : DataChecksumState->launcher_running = false;
946 : 12 : LWLockRelease(DataChecksumsWorkerLock);
947 : 12 : }
948 : :
949 : : /*
950 : : * launcher_cancel_handler
951 : : *
952 : : * Internal routine for reacting to SIGINT and flagging the worker to abort.
953 : : * The worker won't be interrupted immediately but will check for abort flag
954 : : * between each block in a relation.
955 : : */
956 : : static void
32 dgustafsson@postgres 957 :UNC 0 : launcher_cancel_handler(SIGNAL_ARGS)
958 : : {
959 : 0 : int save_errno = errno;
960 : :
961 : 0 : abort_requested = true;
962 : :
963 : : /*
964 : : * There is no sleeping in the main loop, the flag will be checked
965 : : * periodically in ProcessSingleRelationFork. The worker does however
966 : : * sleep when waiting for concurrent transactions to end so we still need
967 : : * to set the latch.
968 : : */
969 : 0 : SetLatch(MyLatch);
970 : :
971 : 0 : errno = save_errno;
972 : 0 : }
973 : :
974 : : /*
975 : : * WaitForAllTransactionsToFinish
976 : : * Blocks awaiting all current transactions to finish
977 : : *
978 : : * Returns when all transactions which are active at the call of the function
979 : : * have ended, or if the postmaster dies while waiting. If the postmaster dies
980 : : * the abort flag will be set to indicate that the caller of this shouldn't
981 : : * proceed.
982 : : *
983 : : * NB: this will return early, if aborted by SIGINT or if the target state
984 : : * is changed while we're running.
985 : : */
986 : : static void
32 dgustafsson@postgres 987 :GNC 8 : WaitForAllTransactionsToFinish(void)
988 : : {
989 : : TransactionId waitforxid;
990 : :
991 : 8 : LWLockAcquire(XidGenLock, LW_SHARED);
992 : 8 : waitforxid = XidFromFullTransactionId(TransamVariables->nextXid);
993 : 8 : LWLockRelease(XidGenLock);
994 : :
995 [ - + ]: 8 : while (TransactionIdPrecedes(GetOldestActiveTransactionId(false, true), waitforxid))
996 : : {
997 : : char activity[64];
998 : : int rc;
999 : :
1000 : : /* Oldest running xid is older than us, so wait */
32 dgustafsson@postgres 1001 :UNC 0 : snprintf(activity,
1002 : : sizeof(activity),
1003 : : "Waiting for current transactions to finish (waiting for %u)",
1004 : : waitforxid);
1005 : 0 : pgstat_report_activity(STATE_RUNNING, activity);
1006 : :
1007 : : /* Retry every 3 seconds */
1008 : 0 : ResetLatch(MyLatch);
1009 : 0 : rc = WaitLatch(MyLatch,
1010 : : WL_LATCH_SET | WL_TIMEOUT | WL_POSTMASTER_DEATH,
1011 : : 3000,
1012 : : WAIT_EVENT_CHECKSUM_ENABLE_STARTCONDITION);
1013 : :
1014 : : /*
1015 : : * If the postmaster died we won't be able to enable checksums
1016 : : * cluster-wide so abort and hope to continue when restarted.
1017 : : */
1018 [ # # ]: 0 : if (rc & WL_POSTMASTER_DEATH)
1019 [ # # ]: 0 : ereport(FATAL,
1020 : : errcode(ERRCODE_ADMIN_SHUTDOWN),
1021 : : errmsg("postmaster exited during data checksums processing"),
1022 : : errhint("Data checksums processing must be restarted manually after cluster restart."));
1023 : :
1024 [ # # ]: 0 : CHECK_FOR_INTERRUPTS();
5 1025 [ # # ]: 0 : CHECK_FOR_ABORT_REQUEST();
1026 : :
32 1027 [ # # ]: 0 : if (abort_requested)
1028 : 0 : break;
1029 : : }
1030 : :
32 dgustafsson@postgres 1031 :GNC 8 : pgstat_report_activity(STATE_IDLE, NULL);
1032 : 8 : return;
1033 : : }
1034 : :
1035 : : /*
1036 : : * DataChecksumsWorkerLauncherMain
1037 : : *
1038 : : * Main function for launching dynamic background workers for processing data
1039 : : * checksums in databases. This function has the bgworker management, with
1040 : : * ProcessAllDatabases being responsible for looping over the databases and
1041 : : * initiating processing.
1042 : : */
1043 : : void
1044 : 12 : DataChecksumsWorkerLauncherMain(Datum arg)
1045 : : {
1046 : :
1047 [ - + ]: 12 : ereport(DEBUG1,
1048 : : errmsg("background worker \"datachecksums launcher\" started"));
1049 : :
1050 : 12 : pqsignal(SIGTERM, die);
1051 : 12 : pqsignal(SIGINT, launcher_cancel_handler);
1052 : 12 : pqsignal(SIGUSR1, procsignal_sigusr1_handler);
21 andrew@dunslane.net 1053 : 12 : pqsignal(SIGUSR2, PG_SIG_IGN);
1054 : :
32 dgustafsson@postgres 1055 : 12 : BackgroundWorkerUnblockSignals();
1056 : :
1057 : 12 : MyBackendType = B_DATACHECKSUMSWORKER_LAUNCHER;
1058 : 12 : init_ps_display(NULL);
1059 : :
1060 : 12 : INJECTION_POINT("datachecksumsworker-launcher-delay", NULL);
1061 : :
1062 : 12 : LWLockAcquire(DataChecksumsWorkerLock, LW_EXCLUSIVE);
1063 : :
1064 [ - + ]: 12 : if (DataChecksumState->launcher_running)
1065 : : {
32 dgustafsson@postgres 1066 [ # # ]:UNC 0 : ereport(LOG,
1067 : : errmsg("background worker \"datachecksums launcher\" already running, exiting"));
1068 : : /* Launcher was already running, let it finish */
1069 : 0 : LWLockRelease(DataChecksumsWorkerLock);
1070 : 0 : return;
1071 : : }
1072 : :
5 dgustafsson@postgres 1073 :GNC 12 : on_shmem_exit(launcher_exit, 0);
32 1074 : 12 : launcher_running = true;
1075 : :
1076 : : /* Initialize a connection to shared catalogs only */
1077 : 12 : BackgroundWorkerInitializeConnectionByOid(InvalidOid, InvalidOid, 0);
1078 : :
1079 : 12 : operation = DataChecksumState->launch_operation;
1080 : 12 : DataChecksumState->launcher_running = true;
1081 : 12 : DataChecksumState->operation = operation;
1082 : 12 : DataChecksumState->cost_delay = DataChecksumState->launch_cost_delay;
1083 : 12 : DataChecksumState->cost_limit = DataChecksumState->launch_cost_limit;
1084 : 12 : LWLockRelease(DataChecksumsWorkerLock);
1085 : :
1086 : : /*
1087 : : * The target state can change while we are busy enabling/disabling
1088 : : * checksums, if the user calls pg_disable/enable_data_checksums() before
1089 : : * we are finished with the previous request. In that case, we will loop
1090 : : * back here, to process the new request.
1091 : : */
1092 : 12 : again:
1093 : :
1094 : 12 : pgstat_progress_start_command(PROGRESS_COMMAND_DATACHECKSUMS,
1095 : : InvalidOid);
1096 : :
1097 [ + + ]: 12 : if (operation == ENABLE_DATACHECKSUMS)
1098 : : {
1099 : : /*
1100 : : * If we are asked to enable checksums in a cluster which already has
1101 : : * checksums enabled, exit immediately as there is nothing more to do.
1102 : : */
1103 [ - + ]: 8 : if (DataChecksumsNeedVerify())
32 dgustafsson@postgres 1104 :UNC 0 : goto done;
1105 : :
32 dgustafsson@postgres 1106 [ + - ]:GNC 8 : ereport(LOG,
1107 : : errmsg("enabling data checksums requested, starting data checksum calculation"));
1108 : :
1109 : : /*
1110 : : * Set the state to inprogress-on and wait on the procsignal barrier.
1111 : : */
1112 : 8 : pgstat_progress_update_param(PROGRESS_DATACHECKSUMS_PHASE,
1113 : : PROGRESS_DATACHECKSUMS_PHASE_ENABLING);
1114 : 8 : SetDataChecksumsOnInProgress();
1115 : :
1116 : : /*
1117 : : * All backends are now in inprogress-on state and are writing data
1118 : : * checksums. Start processing all data at rest.
1119 : : */
1120 [ - + ]: 8 : if (!ProcessAllDatabases())
1121 : : {
1122 : : /*
1123 : : * If the target state changed during processing then it's not a
1124 : : * failure, so restart processing instead.
1125 : : */
32 dgustafsson@postgres 1126 :UNC 0 : LWLockAcquire(DataChecksumsWorkerLock, LW_EXCLUSIVE);
1127 [ # # ]: 0 : if (DataChecksumState->launch_operation != operation)
1128 : : {
1129 : 0 : LWLockRelease(DataChecksumsWorkerLock);
1130 : 0 : goto done;
1131 : : }
1132 : 0 : LWLockRelease(DataChecksumsWorkerLock);
1133 [ # # ]: 0 : ereport(ERROR,
1134 : : errcode(ERRCODE_INSUFFICIENT_RESOURCES),
1135 : : errmsg("unable to enable data checksums in cluster"));
1136 : : }
1137 : :
1138 : : /*
1139 : : * Data checksums have been set on all pages, set the state to on in
1140 : : * order to instruct backends to validate checksums on reading.
1141 : : */
32 dgustafsson@postgres 1142 :GNC 6 : SetDataChecksumsOn();
1143 : :
1144 [ + - ]: 6 : ereport(LOG,
1145 : : errmsg("data checksums are now enabled"));
1146 : : }
1147 [ + - ]: 4 : else if (operation == DISABLE_DATACHECKSUMS)
1148 : : {
1149 [ + - ]: 4 : ereport(LOG,
1150 : : errmsg("disabling data checksums requested"));
1151 : :
1152 : 4 : pgstat_progress_update_param(PROGRESS_DATACHECKSUMS_PHASE,
1153 : : PROGRESS_DATACHECKSUMS_PHASE_DISABLING);
1154 : 4 : SetDataChecksumsOff();
1155 [ + - ]: 4 : ereport(LOG,
1156 : : errmsg("data checksums are now disabled"));
1157 : : }
1158 : : else
32 dgustafsson@postgres 1159 :UNC 0 : Assert(false);
1160 : :
32 dgustafsson@postgres 1161 :GNC 10 : done:
1162 : :
1163 : : /*
1164 : : * This state will only be displayed for a fleeting moment, but for the
1165 : : * sake of correctness it is still added before ending the command.
1166 : : */
1167 : 10 : pgstat_progress_update_param(PROGRESS_DATACHECKSUMS_PHASE,
1168 : : PROGRESS_DATACHECKSUMS_PHASE_DONE);
1169 : :
1170 : : /*
1171 : : * All done. But before we exit, check if the target state was changed
1172 : : * while we were running. In that case we will have to start all over
1173 : : * again.
1174 : : */
1175 : 10 : LWLockAcquire(DataChecksumsWorkerLock, LW_EXCLUSIVE);
1176 [ - + ]: 10 : if (DataChecksumState->launch_operation != operation)
1177 : : {
32 dgustafsson@postgres 1178 :UNC 0 : DataChecksumState->operation = DataChecksumState->launch_operation;
1179 : 0 : operation = DataChecksumState->launch_operation;
1180 : 0 : DataChecksumState->cost_delay = DataChecksumState->launch_cost_delay;
1181 : 0 : DataChecksumState->cost_limit = DataChecksumState->launch_cost_limit;
1182 : 0 : LWLockRelease(DataChecksumsWorkerLock);
1183 : 0 : goto again;
1184 : : }
1185 : :
1186 : : /* Shut down progress reporting as we are done */
32 dgustafsson@postgres 1187 :GNC 10 : pgstat_progress_end_command();
1188 : :
1189 : 10 : launcher_running = false;
1190 : 10 : DataChecksumState->launcher_running = false;
1191 : 10 : LWLockRelease(DataChecksumsWorkerLock);
1192 : : }
1193 : :
1194 : : /*
1195 : : * ProcessAllDatabases
1196 : : * Compute the list of all databases and process checksums in each
1197 : : *
1198 : : * This will generate a list of databases to process for enabling checksums.
1199 : : * If a database encounters a failure then processing will end immediately and
1200 : : * return an error.
1201 : : */
1202 : : static bool
1203 : 8 : ProcessAllDatabases(void)
1204 : : {
1205 : : List *DatabaseList;
1206 : 8 : int cumulative_total = 0;
1207 : :
1208 : : /* Set up so first run processes shared catalogs, not once in every db */
5 1209 : 8 : LWLockAcquire(DataChecksumsWorkerLock, LW_EXCLUSIVE);
32 1210 : 8 : DataChecksumState->process_shared_catalogs = true;
5 1211 : 8 : LWLockRelease(DataChecksumsWorkerLock);
1212 : :
1213 : : /* Get a list of all databases to process */
32 1214 : 8 : WaitForAllTransactionsToFinish();
1215 : 8 : DatabaseList = BuildDatabaseList();
1216 : :
1217 : : /*
1218 : : * Update progress reporting with the total number of databases we need to
1219 : : * process. This number should not be changed during processing, the
1220 : : * columns for processed databases is instead increased such that it can
1221 : : * be compared against the total.
1222 : : */
1223 : : {
1224 : 8 : const int index[] = {
1225 : : PROGRESS_DATACHECKSUMS_DBS_TOTAL,
1226 : : PROGRESS_DATACHECKSUMS_DBS_DONE,
1227 : : PROGRESS_DATACHECKSUMS_RELS_TOTAL,
1228 : : PROGRESS_DATACHECKSUMS_RELS_DONE,
1229 : : PROGRESS_DATACHECKSUMS_BLOCKS_TOTAL,
1230 : : PROGRESS_DATACHECKSUMS_BLOCKS_DONE,
1231 : : };
1232 : :
1233 : : int64 vals[6];
1234 : :
1235 : 8 : vals[0] = list_length(DatabaseList);
1236 : 8 : vals[1] = 0;
1237 : : /* translated to NULL */
1238 : 8 : vals[2] = -1;
1239 : 8 : vals[3] = -1;
1240 : 8 : vals[4] = -1;
1241 : 8 : vals[5] = -1;
1242 : :
1243 : 8 : pgstat_progress_update_multi_param(6, index, vals);
1244 : : }
1245 : :
1246 [ + - + + : 32 : foreach_ptr(DataChecksumsWorkerDatabase, db, DatabaseList)
+ + ]
1247 : : {
1248 : : DataChecksumsWorkerResult result;
1249 : :
1250 : 20 : result = ProcessDatabase(db);
1251 : :
1252 : : #ifdef USE_INJECTION_POINTS
1253 : : /* Allow a test process to alter the result of the operation */
29 1254 [ + + ]: 19 : if (IS_INJECTION_POINT_ATTACHED("datachecksumsworker-fail-db-result"))
1255 : : {
1256 : 1 : result = DATACHECKSUMSWORKER_FAILED;
1257 : 1 : INJECTION_POINT_CACHED("datachecksumsworker-fail-db-result",
1258 : : db->dbname);
1259 : : }
1260 : : #endif
1261 : :
32 1262 : 19 : pgstat_progress_update_param(PROGRESS_DATACHECKSUMS_DBS_DONE,
1263 : : ++cumulative_total);
1264 : :
1265 [ + + ]: 19 : if (result == DATACHECKSUMSWORKER_FAILED)
1266 : : {
1267 : : /*
1268 : : * Disable checksums on cluster, because we failed one of the
1269 : : * databases and this is an all or nothing process.
1270 : : */
1271 : 1 : SetDataChecksumsOff();
1272 [ + - ]: 1 : ereport(ERROR,
1273 : : errcode(ERRCODE_INSUFFICIENT_RESOURCES),
1274 : : errmsg("data checksums failed to get enabled in all databases, aborting"),
1275 : : errhint("The server log might have more information on the cause of the error."));
1276 : : }
1277 [ + - - + ]: 18 : else if (result == DATACHECKSUMSWORKER_ABORTED || abort_requested)
1278 : : {
1279 : : /* Abort flag set, so exit the whole process */
32 dgustafsson@postgres 1280 :UNC 0 : return false;
1281 : : }
1282 : :
1283 : : /*
1284 : : * When one database has completed, it will have done shared catalogs
1285 : : * so we don't have to process them again.
1286 : : */
5 dgustafsson@postgres 1287 :GNC 18 : LWLockAcquire(DataChecksumsWorkerLock, LW_EXCLUSIVE);
32 1288 : 18 : DataChecksumState->process_shared_catalogs = false;
5 1289 : 18 : LWLockRelease(DataChecksumsWorkerLock);
1290 : : }
1291 : :
32 1292 : 6 : FreeDatabaseList(DatabaseList);
1293 : :
1294 : 6 : pgstat_progress_update_param(PROGRESS_DATACHECKSUMS_PHASE,
1295 : : PROGRESS_DATACHECKSUMS_PHASE_WAITING_BARRIER);
1296 : 6 : return true;
1297 : : }
1298 : :
1299 : : /*
1300 : : * DataChecksumsShmemRequest
1301 : : * Request datachecksumsworker-related shared memory
1302 : : */
1303 : : static void
29 heikki.linnakangas@i 1304 : 1244 : DataChecksumsShmemRequest(void *arg)
1305 : : {
1306 : 1244 : ShmemRequestStruct(.name = "DataChecksumsWorker Data",
1307 : : .size = sizeof(DataChecksumsStateStruct),
1308 : : .ptr = (void **) &DataChecksumState,
1309 : : );
32 dgustafsson@postgres 1310 : 1244 : }
1311 : :
1312 : : /*
1313 : : * DatabaseExists
1314 : : *
1315 : : * Scans the system catalog to check if a database with the given Oid exists
1316 : : * and returns true if it is found and valid, else false. Note, we cannot use
1317 : : * database_is_invalid_oid here as it will ERROR out, and we want to gracefully
1318 : : * handle errors.
1319 : : */
1320 : : static bool
32 dgustafsson@postgres 1321 :UNC 0 : DatabaseExists(Oid dboid)
1322 : : {
1323 : : Relation rel;
1324 : : ScanKeyData skey;
1325 : : SysScanDesc scan;
1326 : : bool found;
1327 : : HeapTuple tuple;
1328 : : Form_pg_database pg_database_tuple;
1329 : :
1330 : 0 : StartTransactionCommand();
1331 : :
1332 : 0 : rel = table_open(DatabaseRelationId, AccessShareLock);
1333 : 0 : ScanKeyInit(&skey,
1334 : : Anum_pg_database_oid,
1335 : : BTEqualStrategyNumber, F_OIDEQ,
1336 : : ObjectIdGetDatum(dboid));
1337 : 0 : scan = systable_beginscan(rel, DatabaseOidIndexId, true, SnapshotSelf,
1338 : : 1, &skey);
1339 : 0 : tuple = systable_getnext(scan);
1340 : 0 : found = HeapTupleIsValid(tuple);
1341 : :
1342 : : /* If the Oid exists, ensure that it's not partially dropped */
5 1343 [ # # ]: 0 : if (found)
1344 : : {
1345 : 0 : pg_database_tuple = (Form_pg_database) GETSTRUCT(tuple);
1346 [ # # ]: 0 : if (database_is_invalid_form(pg_database_tuple))
1347 : 0 : found = false;
1348 : : }
1349 : :
32 1350 : 0 : systable_endscan(scan);
1351 : 0 : table_close(rel, AccessShareLock);
1352 : :
1353 : 0 : CommitTransactionCommand();
1354 : :
1355 : 0 : return found;
1356 : : }
1357 : :
1358 : : /*
1359 : : * BuildDatabaseList
1360 : : * Compile a list of all currently available databases in the cluster
1361 : : *
1362 : : * This creates the list of databases for the datachecksumsworker workers to
1363 : : * add checksums to. If the caller wants to ensure that no concurrently
1364 : : * running CREATE DATABASE calls exist, this needs to be preceded by a call
1365 : : * to WaitForAllTransactionsToFinish().
1366 : : */
1367 : : static List *
32 dgustafsson@postgres 1368 :GNC 8 : BuildDatabaseList(void)
1369 : : {
1370 : 8 : List *DatabaseList = NIL;
1371 : : Relation rel;
1372 : : TableScanDesc scan;
1373 : : HeapTuple tup;
1374 : 8 : MemoryContext ctx = CurrentMemoryContext;
1375 : : MemoryContext oldctx;
1376 : :
1377 : 8 : StartTransactionCommand();
1378 : :
1379 : 8 : rel = table_open(DatabaseRelationId, AccessShareLock);
1380 : 8 : scan = table_beginscan_catalog(rel, 0, NULL);
1381 : :
1382 [ + + ]: 32 : while (HeapTupleIsValid(tup = heap_getnext(scan, ForwardScanDirection)))
1383 : : {
1384 : 24 : Form_pg_database pgdb = (Form_pg_database) GETSTRUCT(tup);
1385 : : DataChecksumsWorkerDatabase *db;
1386 : :
1387 : 24 : oldctx = MemoryContextSwitchTo(ctx);
1388 : :
1389 : 24 : db = (DataChecksumsWorkerDatabase *) palloc0(sizeof(DataChecksumsWorkerDatabase));
1390 : :
1391 : 24 : db->dboid = pgdb->oid;
1392 : 24 : db->dbname = pstrdup(NameStr(pgdb->datname));
1393 : :
1394 : 24 : DatabaseList = lappend(DatabaseList, db);
1395 : :
1396 : 24 : MemoryContextSwitchTo(oldctx);
1397 : : }
1398 : :
1399 : 8 : table_endscan(scan);
1400 : 8 : table_close(rel, AccessShareLock);
1401 : :
1402 : 8 : CommitTransactionCommand();
1403 : :
1404 : 8 : return DatabaseList;
1405 : : }
1406 : :
1407 : : static void
1408 : 6 : FreeDatabaseList(List *dblist)
1409 : : {
1410 [ - + ]: 6 : if (!dblist)
32 dgustafsson@postgres 1411 :UNC 0 : return;
1412 : :
32 dgustafsson@postgres 1413 [ + - + + :GNC 30 : foreach_ptr(DataChecksumsWorkerDatabase, db, dblist)
+ + ]
1414 : : {
1415 [ + - ]: 18 : if (db->dbname != NULL)
1416 : 18 : pfree(db->dbname);
1417 : : }
1418 : :
1419 : 6 : list_free_deep(dblist);
1420 : : }
1421 : :
1422 : : /*
1423 : : * BuildRelationList
1424 : : * Compile a list of relations in the database
1425 : : *
1426 : : * Returns a list of OIDs for the request relation types. If temp_relations
1427 : : * is True then only temporary relations are returned. If temp_relations is
1428 : : * False then non-temporary relations which have data checksums are returned.
1429 : : * If include_shared is True then shared relations are included as well in a
1430 : : * non-temporary list. include_shared has no relevance when building a list of
1431 : : * temporary relations.
1432 : : */
1433 : : static List *
1434 : 59 : BuildRelationList(bool temp_relations, bool include_shared)
1435 : : {
1436 : 59 : List *RelationList = NIL;
1437 : : Relation rel;
1438 : : TableScanDesc scan;
1439 : : HeapTuple tup;
1440 : 59 : MemoryContext ctx = CurrentMemoryContext;
1441 : : MemoryContext oldctx;
1442 : :
1443 : 59 : StartTransactionCommand();
1444 : :
1445 : 59 : rel = table_open(RelationRelationId, AccessShareLock);
1446 : 59 : scan = table_beginscan_catalog(rel, 0, NULL);
1447 : :
1448 [ + + ]: 26749 : while (HeapTupleIsValid(tup = heap_getnext(scan, ForwardScanDirection)))
1449 : : {
1450 : 26690 : Form_pg_class pgc = (Form_pg_class) GETSTRUCT(tup);
1451 : :
1452 : : /* Only include temporary relations when explicitly asked to */
1453 [ + + ]: 26690 : if (pgc->relpersistence == RELPERSISTENCE_TEMP)
1454 : : {
1455 [ + + ]: 2 : if (!temp_relations)
1456 : 1 : continue;
1457 : : }
1458 : : else
1459 : : {
1460 : : /*
1461 : : * If we are only interested in temp relations then continue
1462 : : * immediately as the current relation isn't a temp relation.
1463 : : */
1464 [ + + ]: 26688 : if (temp_relations)
1465 : 17641 : continue;
1466 : :
1467 [ + + + + : 9047 : if (!RELKIND_HAS_STORAGE(pgc->relkind))
+ - + + +
- ]
1468 : 3240 : continue;
1469 : :
1470 [ + + + + ]: 5807 : if (pgc->relisshared && !include_shared)
1471 : 552 : continue;
1472 : : }
1473 : :
1474 : 5256 : oldctx = MemoryContextSwitchTo(ctx);
1475 : 5256 : RelationList = lappend_oid(RelationList, pgc->oid);
1476 : 5256 : MemoryContextSwitchTo(oldctx);
1477 : : }
1478 : :
1479 : 59 : table_endscan(scan);
1480 : 59 : table_close(rel, AccessShareLock);
1481 : :
1482 : 59 : CommitTransactionCommand();
1483 : :
1484 : 59 : return RelationList;
1485 : : }
1486 : :
1487 : : /*
1488 : : * DataChecksumsWorkerMain
1489 : : *
1490 : : * Main function for enabling checksums in a single database. This is the
1491 : : * function set as the bgw_function_name in the dynamic background worker
1492 : : * process initiated for each database by the worker launcher. After enabling
1493 : : * data checksums in each applicable relation in the database, it will wait for
1494 : : * all temporary relations that were present when the function started to
1495 : : * disappear before returning. This is required since we cannot rewrite
1496 : : * existing temporary relations with data checksums.
1497 : : */
1498 : : void
1499 : 20 : DataChecksumsWorkerMain(Datum arg)
1500 : : {
1501 : 20 : Oid dboid = DatumGetObjectId(arg);
1502 : 20 : List *RelationList = NIL;
1503 : 20 : List *InitialTempTableList = NIL;
1504 : : BufferAccessStrategy strategy;
1505 : 20 : bool aborted = false;
1506 : : int64 rels_done;
1507 : : #ifdef USE_INJECTION_POINTS
29 1508 : 20 : bool retried = false;
1509 : : #endif
1510 : :
32 1511 : 20 : operation = ENABLE_DATACHECKSUMS;
1512 : :
1513 : 20 : pqsignal(SIGTERM, die);
1514 : 20 : pqsignal(SIGUSR1, procsignal_sigusr1_handler);
1515 : :
1516 : 20 : BackgroundWorkerUnblockSignals();
1517 : :
1518 : 20 : MyBackendType = B_DATACHECKSUMSWORKER_WORKER;
1519 : 20 : init_ps_display(NULL);
1520 : :
1521 : 20 : BackgroundWorkerInitializeConnectionByOid(dboid, InvalidOid,
1522 : : BGWORKER_BYPASS_ALLOWCONN);
1523 : :
1524 : : /* worker will have a separate entry in pg_stat_progress_data_checksums */
1525 : 20 : pgstat_progress_start_command(PROGRESS_COMMAND_DATACHECKSUMS,
1526 : : InvalidOid);
1527 : :
1528 : : /*
1529 : : * Get a list of all temp tables present as we start in this database. We
1530 : : * need to wait until they are all gone until we are done, since we cannot
1531 : : * access these relations and modify them.
1532 : : */
1533 : 20 : InitialTempTableList = BuildRelationList(true, false);
1534 : :
1535 : : /*
1536 : : * Enable vacuum cost delay, if any. While this process isn't doing any
1537 : : * vacuuming, we are re-using the infrastructure that vacuum cost delay
1538 : : * provides rather than inventing something bespoke. This is an internal
1539 : : * implementation detail and care should be taken to avoid it bleeding
1540 : : * through to the user to avoid confusion.
1541 : : */
1542 : 20 : VacuumCostDelay = DataChecksumState->cost_delay;
1543 : 20 : VacuumCostLimit = DataChecksumState->cost_limit;
1544 : 20 : VacuumCostActive = (VacuumCostDelay > 0);
1545 : 20 : VacuumCostBalance = 0;
1546 : 20 : VacuumCostPageHit = 0;
1547 : 20 : VacuumCostPageMiss = 0;
1548 : 20 : VacuumCostPageDirty = 0;
1549 : :
1550 : : /*
1551 : : * Create and set the vacuum strategy as our buffer strategy.
1552 : : */
1553 : 20 : strategy = GetAccessStrategy(BAS_VACUUM);
1554 : :
1555 : 20 : RelationList = BuildRelationList(false,
1556 : 20 : DataChecksumState->process_shared_catalogs);
1557 : :
1558 : : /* Update the total number of relations to be processed in this DB. */
1559 : : {
1560 : 20 : const int index[] = {
1561 : : PROGRESS_DATACHECKSUMS_RELS_TOTAL,
1562 : : PROGRESS_DATACHECKSUMS_RELS_DONE
1563 : : };
1564 : :
1565 : : int64 vals[2];
1566 : :
1567 : 20 : vals[0] = list_length(RelationList);
1568 : 20 : vals[1] = 0;
1569 : :
1570 : 20 : pgstat_progress_update_multi_param(2, index, vals);
1571 : : }
1572 : :
1573 : : /* Process the relations */
1574 : 20 : rels_done = 0;
1575 [ + - + + : 5020 : foreach_oid(reloid, RelationList)
+ + ]
1576 : : {
5 1577 : 4982 : bool costs_updated = false;
1578 : :
32 1579 [ - + ]: 4982 : if (!ProcessSingleRelationByOid(reloid, strategy))
1580 : : {
32 dgustafsson@postgres 1581 :UNC 0 : aborted = true;
1582 : 0 : break;
1583 : : }
1584 : :
32 dgustafsson@postgres 1585 :GNC 4982 : pgstat_progress_update_param(PROGRESS_DATACHECKSUMS_RELS_DONE,
1586 : : ++rels_done);
5 1587 [ + + ]: 4982 : CHECK_FOR_INTERRUPTS();
1588 [ - + ]: 4981 : CHECK_FOR_ABORT_REQUEST();
1589 : :
1590 [ - + ]: 4981 : if (abort_requested)
5 dgustafsson@postgres 1591 :UNC 0 : break;
1592 : :
1593 : : /*
1594 : : * Check if the cost settings changed during runtime and if so, update
1595 : : * to reflect the new values and signal that the access strategy needs
1596 : : * to be refreshed.
1597 : : */
5 dgustafsson@postgres 1598 :GNC 4981 : LWLockAcquire(DataChecksumsWorkerLock, LW_EXCLUSIVE);
1599 [ + - ]: 4981 : if ((DataChecksumState->launch_cost_delay != DataChecksumState->cost_delay)
1600 [ - + ]: 4981 : || (DataChecksumState->launch_cost_limit != DataChecksumState->cost_limit))
1601 : : {
5 dgustafsson@postgres 1602 :UNC 0 : costs_updated = true;
1603 : 0 : VacuumCostDelay = DataChecksumState->launch_cost_delay;
1604 : 0 : VacuumCostLimit = DataChecksumState->launch_cost_limit;
1605 : 0 : VacuumCostActive = (VacuumCostDelay > 0);
1606 : :
1607 : 0 : DataChecksumState->cost_delay = DataChecksumState->launch_cost_delay;
1608 : 0 : DataChecksumState->cost_limit = DataChecksumState->launch_cost_limit;
1609 : : }
1610 : : else
5 dgustafsson@postgres 1611 :GNC 4981 : costs_updated = false;
1612 : 4981 : LWLockRelease(DataChecksumsWorkerLock);
1613 : :
1614 [ - + ]: 4981 : if (costs_updated)
1615 : : {
5 dgustafsson@postgres 1616 :UNC 0 : FreeAccessStrategy(strategy);
1617 : 0 : strategy = GetAccessStrategy(BAS_VACUUM);
1618 : : }
1619 : : }
1620 : :
32 dgustafsson@postgres 1621 :GNC 19 : list_free(RelationList);
5 1622 : 19 : FreeAccessStrategy(strategy);
1623 : :
1624 [ + - - + ]: 19 : if (aborted || abort_requested)
1625 : : {
5 dgustafsson@postgres 1626 :UNC 0 : LWLockAcquire(DataChecksumsWorkerLock, LW_EXCLUSIVE);
32 1627 : 0 : DataChecksumState->success = DATACHECKSUMSWORKER_ABORTED;
5 1628 : 0 : LWLockRelease(DataChecksumsWorkerLock);
32 1629 [ # # ]: 0 : ereport(DEBUG1,
1630 : : errmsg("data checksum processing aborted in database OID %u",
1631 : : dboid));
1632 : 0 : return;
1633 : : }
1634 : :
1635 : : /* The worker is about to wait for temporary tables to go away. */
32 dgustafsson@postgres 1636 :GNC 19 : pgstat_progress_update_param(PROGRESS_DATACHECKSUMS_PHASE,
1637 : : PROGRESS_DATACHECKSUMS_PHASE_WAITING_TEMPREL);
1638 : :
1639 : : /*
1640 : : * Wait for all temp tables that existed when we started to go away. This
1641 : : * is necessary since we cannot "reach" them to enable checksums. Any temp
1642 : : * tables created after we started will already have checksums in them
1643 : : * (due to the "inprogress-on" state), so no need to wait for those.
1644 : : */
1645 : : for (;;)
32 dgustafsson@postgres 1646 :UNC 0 : {
1647 : : List *CurrentTempTables;
1648 : : int numleft;
1649 : : char activity[64];
1650 : :
32 dgustafsson@postgres 1651 :GNC 19 : CurrentTempTables = BuildRelationList(true, false);
1652 : 19 : numleft = 0;
1653 [ - + - - : 38 : foreach_oid(tmptbloid, InitialTempTableList)
+ + ]
1654 : : {
32 dgustafsson@postgres 1655 [ # # ]:UNC 0 : if (list_member_oid(CurrentTempTables, tmptbloid))
1656 : 0 : numleft++;
1657 : : }
32 dgustafsson@postgres 1658 :GNC 19 : list_free(CurrentTempTables);
1659 : :
1660 : : #ifdef USE_INJECTION_POINTS
29 1661 [ - + ]: 19 : if (IS_INJECTION_POINT_ATTACHED("datachecksumsworker-fake-temptable-wait"))
1662 : : {
1663 : : /* Make sure to just cause one retry */
29 dgustafsson@postgres 1664 [ # # # # ]:UNC 0 : if (!retried && numleft == 0)
1665 : : {
1666 : 0 : numleft = 1;
1667 : 0 : retried = true;
1668 : :
1669 : 0 : INJECTION_POINT_CACHED("datachecksumsworker-fake-temptable-wait", NULL);
1670 : : }
1671 : : }
1672 : : #endif
1673 : :
32 dgustafsson@postgres 1674 [ + - ]:GNC 19 : if (numleft == 0)
1675 : 19 : break;
1676 : :
1677 : : /*
1678 : : * At least one temp table is left to wait for, indicate in pgstat
1679 : : * activity and progress reporting.
1680 : : */
32 dgustafsson@postgres 1681 :UNC 0 : snprintf(activity,
1682 : : sizeof(activity),
1683 : : "Waiting for %d temp tables to be removed", numleft);
1684 : 0 : pgstat_report_activity(STATE_RUNNING, activity);
1685 : :
1686 : : /* Retry every 3 seconds */
1687 : 0 : ResetLatch(MyLatch);
1688 : 0 : (void) WaitLatch(MyLatch,
1689 : : WL_LATCH_SET | WL_TIMEOUT | WL_EXIT_ON_PM_DEATH,
1690 : : 3000,
1691 : : WAIT_EVENT_CHECKSUM_ENABLE_TEMPTABLE_WAIT);
1692 : :
1693 [ # # ]: 0 : CHECK_FOR_INTERRUPTS();
5 1694 [ # # ]: 0 : CHECK_FOR_ABORT_REQUEST();
1695 : :
32 1696 [ # # # # ]: 0 : if (aborted || abort_requested)
1697 : : {
5 1698 : 0 : LWLockAcquire(DataChecksumsWorkerLock, LW_EXCLUSIVE);
32 1699 : 0 : DataChecksumState->success = DATACHECKSUMSWORKER_ABORTED;
5 1700 : 0 : LWLockRelease(DataChecksumsWorkerLock);
32 1701 [ # # ]: 0 : ereport(LOG,
1702 : : errmsg("data checksum processing aborted in database OID %u",
1703 : : dboid));
1704 : 0 : return;
1705 : : }
1706 : : }
1707 : :
32 dgustafsson@postgres 1708 :GNC 19 : list_free(InitialTempTableList);
1709 : :
1710 : : /* worker done */
1711 : 19 : pgstat_progress_end_command();
1712 : :
29 1713 : 19 : LWLockAcquire(DataChecksumsWorkerLock, LW_EXCLUSIVE);
32 1714 : 19 : DataChecksumState->success = DATACHECKSUMSWORKER_SUCCESSFUL;
29 1715 : 19 : LWLockRelease(DataChecksumsWorkerLock);
1716 : : }
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