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* Add support for runtime arguments in injection pointsMichael Paquier12 days
| | | | | | | | | | | | | | | | | | | The macros INJECTION_POINT() and INJECTION_POINT_CACHED() are extended with an optional argument that can be passed down to the callback attached when an injection point is run, giving to callbacks the possibility to manipulate a stack state given by the caller. The existing callbacks in modules injection_points and test_aio have their declarations adjusted based on that. da7226993fd4 (core AIO infrastructure) and 93bc3d75d8e1 (test_aio) and been relying on a set of workarounds where a static variable called pgaio_inj_cur_handle is used as runtime argument in the injection point callbacks used by the AIO tests, in combination with a TRY/CATCH block to reset the argument value. The infrastructure introduced in this commit will be reused for the AIO tests, simplifying them. Reviewed-by: Greg Burd <greg@burd.me> Discussion: https://postgr.es/m/Z_y9TtnXubvYAApS@paquier.xyz
* Fix typos and grammar in the codeMichael Paquier2025-04-19
| | | | | | | | The large majority of these have been introduced by recent commits done in the v18 development cycle. Author: Alexander Lakhin <exclusion@gmail.com> Discussion: https://postgr.es/m/9a7763ab-5252-429d-a943-b28941e0e28b@gmail.com
* Get rid of WALBufMappingLockAlexander Korotkov2025-04-02
| | | | | | | | | | | | | | | | | | | | | | | | | | | Allow multiple backends to initialize WAL buffers concurrently. This way `MemSet((char *) NewPage, 0, XLOG_BLCKSZ);` can run in parallel without taking a single LWLock in exclusive mode. The new algorithm works as follows: * reserve a page for initialization using XLogCtl->InitializeReserved, * ensure the page is written out, * once the page is initialized, try to advance XLogCtl->InitializedUpTo and signal to waiters using XLogCtl->InitializedUpToCondVar condition variable, * repeat previous steps until we reserve initialization up to the target WAL position, * wait until concurrent initialization finishes using a XLogCtl->InitializedUpToCondVar. Now, multiple backends can, in parallel, concurrently reserve pages, initialize them, and advance XLogCtl->InitializedUpTo to point to the latest initialized page. Author: Yura Sokolov <y.sokolov@postgrespro.ru> Co-authored-by: Alexander Korotkov <aekorotkov@gmail.com> Reviewed-by: Pavel Borisov <pashkin.elfe@gmail.com> Reviewed-by: Tomas Vondra <tomas@vondra.me> Tested-by: Michael Paquier <michael@paquier.xyz>
* Fix guc_malloc calls for consistency and OOM checksDaniel Gustafsson2025-03-27
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | check_createrole_self_grant and check_synchronized_standby_slots were allocating memory on a LOG elevel without checking if the allocation succeeded or not, which would have led to a segfault on allocation failure. On top of that, a number of callsites were using the ERROR level, relying on erroring out rather than returning false to allow the GUC machinery handle it gracefully. Other callsites used WARNING instead of LOG. While neither being not wrong, this changes all check_ functions do it consistently with LOG. init_custom_variable gets a promoted elevel to FATAL to keep the guc_malloc error handling in line with the rest of the error handling in that function which already call FATAL. If we encounter an OOM in this callsite there is no graceful handling to be had, better to error out hard. Backpatch the fix to check_createrole_self_grant down to v16 and the fix to check_synchronized_standby_slots down to v17 where they were introduced. Author: Daniel Gustafsson <daniel@yesql.se> Reported-by: Nikita <pm91.arapov@gmail.com> Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us> Bug: #18845 Discussion: https://postgr.es/m/18845-582c6e10247377ec@postgresql.org Backpatch-through: 16
* Revert "Add redo LSN to pgstats files"Michael Paquier2025-03-17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This reverts commit b860848232aa, that was added as a prerequisite for the support of pgstats data flush across checkpoints, linking a pgstats file to a specific checkpoint redo LSN. As reported, this is proving to be currently problematic when going through a pg_upgrade, that does direct manipulations of the control file in the new cluster. The LSN stored in the pgstats file is not able to cope with any changes done in the control file by pg_upgrade yet, causing the pgstats file to be discarded when starting the new cluster after overriding its redo LSN (one is a `pg_resetwal -l` where the new cluster's start LSN is bumped by a hardcoded value of 8 segments, see copy_xact_xlog_xid). The least painful path going forward is likely going to be a refactor of the pgstats code so as it is possible to read and write some of its data with some routines in src/common/, so as pg_upgrade or pg_resetwal are able to update its data. The main point is that we are going to need a LSN in the stats file should we make it written at checkpoint time and not only as part of a shutdown sequence. It is too late to dive into these details for v18, so let's revert the change, and let's try to figure out all the details in the next release cycle. The pgstats file is currently only written as part of a shutdown sequence, and its contents are still lost on crash, same as older releases. Bump PGSTAT_FILE_FORMAT_ID. Reported-by: Tom Lane <tgl@sss.pgh.pa.us> Discussion: https://postgr.es/m/2563883.1741826489@sss.pgh.pa.us
* Re-add GUC track_wal_io_timingMichael Paquier2025-02-26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | This commit is a rework of 2421e9a51d20, about which Andres Freund has raised some concerns as it is valuable to have both track_io_timing and track_wal_io_timing in some cases, as the WAL write and fsync paths can be a major bottleneck for some workloads. Hence, it can be relevant to not calculate the WAL timings in environments where pg_test_timing performs poorly while capturing some IO data under track_io_timing for the non-WAL IO paths. The opposite can be also true: it should be possible to disable the non-WAL timings and enable the WAL timings (the previous GUC setups allowed this possibility). track_wal_io_timing is added back in this commit, controlling if WAL timings should be calculated in pg_stat_io for the read, fsync and write paths, as done previously with pg_stat_wal. pg_stat_wal previously tracked only the sync and write parts (now removed), read stats is new data tracked in pg_stat_io, all three are aggregated if track_wal_io_timing is enabled. The read part matters during recovery or if a XLogReader is used. Extra note: more control over if the types of timings calculated in pg_stat_io could be done with a GUC that lists pairs of (IOObject,IOOp). Reported-by: Andres Freund <andres@anarazel.de> Author: Bertrand Drouvot <bertranddrouvot.pg@gmail.com> Co-authored-by: Michael Paquier <michael@paquier.xyz> Discussion: https://postgr.es/m/3opf2wh2oljco6ldyqf7ukabw3jijnnhno6fjb4mlu6civ5h24@fcwmhsgmlmzu
* Remove read/sync fields from pg_stat_wal and GUC track_wal_io_timingMichael Paquier2025-02-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | The four following attributes are removed from pg_stat_wal: * wal_write * wal_sync * wal_write_time * wal_sync_time a051e71e28a1 has added an equivalent of this information in pg_stat_io with more granularity as this now spreads across the backend types, IO context and IO objects. So, keeping the same information in pg_stat_wal has little benefits. Another benefit of this commit is the removal of PendingWalStats, simplifying an upcoming patch to add per-backend WAL statistics, which already support IO statistics and which have access to the write/sync stats data of WAL. The GUC track_wal_io_timing, that was used to enable or disable the aggregation of the write and sync timings for WAL, is also removed. pgstat_prepare_io_time() is simplified. Bump catalog version. Bump PGSTAT_FILE_FORMAT_ID, due to the update of PgStat_WalStats. Author: Bertrand Drouvot <bertranddrouvot.pg@gmail.com> Discussion: https://postgr.es/m/Z7RkQ0EfYaqqjgz/@ip-10-97-1-34.eu-west-3.compute.internal
* Add default_char_signedness field to ControlFileData.Masahiko Sawada2025-02-21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The signedness of the 'char' type in C is implementation-dependent. For instance, 'signed char' is used by default on x86 CPUs, while 'unsigned char' is used on aarch CPUs. Previously, we accidentally let C implementation signedness affect persistent data. This led to inconsistent results when comparing char data across different platforms. This commit introduces a new 'default_char_signedness' field in ControlFileData to store the signedness of the 'char' type. While this change does not encourage the use of 'char' without explicitly specifying its signedness, this field can be used as a hint to ensure consistent behavior for pre-v18 data files that store data sorted by the 'char' type on disk (e.g., GIN and GiST indexes), especially in cross-platform replication scenarios. Newly created database clusters unconditionally set the default char signedness to true. pg_upgrade (with an upcoming commit) changes this flag for clusters if the source database cluster has signedness=false. As a result, signedness=false setting will become rare over time. If we had known about the problem during the last development cycle that forced initdb (v8.3), we would have made all clusters signed or all clusters unsigned. Making pg_upgrade the only source of signedness=false will cause the population of database clusters to converge toward that retrospective ideal. Bump catalog version (for the catalog changes) and PG_CONTROL_VERSION (for the additions in ControlFileData). Reviewed-by: Noah Misch <noah@leadboat.com> Discussion: https://postgr.es/m/CB11ADBC-0C3F-4FE0-A678-666EE80CBB07%40amazon.com
* Remove various unnecessary (char *) castsPeter Eisentraut2025-02-20
| | | | | | | | Remove a number of (char *) casts that are unnecessary. Or in some cases, rewrite the code to make the purpose of the cast clearer. Reviewed-by: Dagfinn Ilmari Mannsåker <ilmari@ilmari.org> Discussion: https://www.postgresql.org/message-id/flat/fd1fcedb-3492-4fc8-9e3e-74b97f2db6c7%40eisentraut.org
* Invalidate inactive replication slots.Amit Kapila2025-02-19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This commit introduces idle_replication_slot_timeout GUC that allows inactive slots to be invalidated at the time of checkpoint. Because checkpoints happen checkpoint_timeout intervals, there can be some lag between when the idle_replication_slot_timeout was exceeded and when the slot invalidation is triggered at the next checkpoint. To avoid such lags, users can force a checkpoint to promptly invalidate inactive slots. Note that the idle timeout invalidation mechanism is not applicable for slots that do not reserve WAL or for slots on the standby server that are synced from the primary server (i.e., standby slots having 'synced' field 'true'). Synced slots are always considered to be inactive because they don't perform logical decoding to produce changes. The slots can become inactive for a long period if a subscriber is down due to a system error or inaccessible because of network issues. If such a situation persists, it might be more practical to recreate the subscriber rather than attempt to recover the node and wait for it to catch up which could be time-consuming. Then, external tools could create replication slots (e.g., for migrations or upgrades) that may fail to remove them if an error occurs, leaving behind unused slots that take up space and resources. Manually cleaning them up can be tedious and error-prone, and without intervention, these lingering slots can cause unnecessary WAL retention and system bloat. As the duration of idle_replication_slot_timeout is in minutes, any test using that would be time-consuming. We are planning to commit a follow up patch for tests by using the injection point framework. Author: Nisha Moond <nisha.moond412@gmail.com> Author: Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com> Reviewed-by: Peter Smith <smithpb2250@gmail.com> Reviewed-by: Hayato Kuroda <kuroda.hayato@fujitsu.com> Reviewed-by: Vignesh C <vignesh21@gmail.com> Reviewed-by: Amit Kapila <amit.kapila16@gmail.com> Reviewed-by: Hou Zhijie <houzj.fnst@fujitsu.com> Reviewed-by: Bertrand Drouvot <bertranddrouvot.pg@gmail.com> Discussion: https://postgr.es/m/CALj2ACW4aUe-_uFQOjdWCEN-xXoLGhmvRFnL8SNw_TZ5nJe+aw@mail.gmail.com Discussion: https://postgr.es/m/OS0PR01MB5716C131A7D80DAE8CB9E88794FC2@OS0PR01MB5716.jpnprd01.prod.outlook.com
* Revert: Get rid of WALBufMappingLockAlexander Korotkov2025-02-17
| | | | | This commit reverts 6a2275b895. Buildfarm failure on batta spots some concurrency issue, which requires further investigation.
* Move wal_buffers_full from PgStat_PendingWalStats to WalUsageMichael Paquier2025-02-17
| | | | | | | | | | | | | | | | | | | | | | | | wal_buffers_full has been introduced in pg_stat_wal in 8d9a935965f, as some information providing metrics for the tuning of the GUC wal_buffers. WalUsage has been introduced before that in df3b181499. Moving this field is proving to be beneficial for several reasons: - This information can now be made available in more layers, providing more granularity than just pg_stat_wal, on a per-query basis: EXPLAIN, pgss and VACUUM/ANALYZE logs. - A patch is under discussion to provide statistics for WAL at backend level, and this move simplifies a bit the handling of pending statistics. The remaining data in PgStat_PendingWalStats now relates to write/sync counters and times, with equivalents present in pg_stat_io, that backend statistics are able to already track. So this should cut all the dependencies between PgStat_PendingWalStats and WAL stats at backend level. As of this change, wal_buffers_full only shows in pg_stat_wal. Author: Bertrand Drouvot Reviewed-by: Ilia Evdokimov Discussion: https://postgr.es/m/Z6SOha5YFFgvpwQY@ip-10-97-1-34.eu-west-3.compute.internal
* Get rid of WALBufMappingLockAlexander Korotkov2025-02-17
| | | | | | | | | | | | | | | | | | | | | | | | | Allow multiple backends to initialize WAL buffers concurrently. This way `MemSet((char *) NewPage, 0, XLOG_BLCKSZ);` can run in parallel without taking a single LWLock in exclusive mode. The new algorithm works as follows: * reserve a page for initialization using XLogCtl->InitializeReserved, * ensure the page is written out, * once the page is initialized, try to advance XLogCtl->InitializedUpTo and signal to waiters using XLogCtl->InitializedUpToCondVar condition variable, * repeat previous steps until we reserve initialization up to the target WAL position, * wait until concurrent initialization finishes using a XLogCtl->InitializedUpToCondVar. Now, multiple backends can, in parallel, concurrently reserve pages, initialize them, and advance XLogCtl->InitializedUpTo to point to the latest initialized page. Author: Yura Sokolov <y.sokolov@postgrespro.ru> Co-authored-by: Alexander Korotkov <aekorotkov@gmail.com> Reviewed-by: Pavel Borisov <pashkin.elfe@gmail.com>
* Remove unnecessary (char *) casts [xlog]Peter Eisentraut2025-02-13
| | | | | | | | Remove (char *) casts no longer needed after XLogRegisterData() and XLogRegisterBufData() argument type change. Reviewed-by: Dagfinn Ilmari Mannsåker <ilmari@ilmari.org> Discussion: https://www.postgresql.org/message-id/flat/fd1fcedb-3492-4fc8-9e3e-74b97f2db6c7%40eisentraut.org
* Remove unnecessary (char *) casts [mem]Peter Eisentraut2025-02-12
| | | | | | | | | | Remove (char *) casts around memory functions such as memcmp(), memcpy(), or memset() where the cast is useless. Since these functions don't take char * arguments anyway, these casts are at best complicated casts to (void *), about which see commit 7f798aca1d5. Reviewed-by: Dagfinn Ilmari Mannsåker <ilmari@ilmari.org> Discussion: https://www.postgresql.org/message-id/flat/fd1fcedb-3492-4fc8-9e3e-74b97f2db6c7%40eisentraut.org
* Add data for WAL in pg_stat_io and backend statisticsMichael Paquier2025-02-04
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This commit adds WAL IO stats to both pg_stat_io view and per-backend IO statistics (pg_stat_get_backend_io()). This change is possible since f92c854cf406, as WAL IO is not counted in blocks in some code paths where its stats data is measured (like WAL read in xlogreader.c). IOContext gains IOCONTEXT_INIT and IOObject IOOBJECT_WAL, with the following combinations allowed: - IOOBJECT_WAL/IOCONTEXT_NORMAL is used to track I/O operations done on already-created WAL segments. - IOOBJECT_WAL/IOCONTEXT_INIT is used for tracking I/O operations done when initializing WAL segments. The core changes are done in pg_stat_io.c, backend statistics inherit them. Backend statistics and pg_stat_io are now available for the WAL writer, the WAL receiver and the WAL summarizer processes. I/O timing data is controlled by the GUC track_io_timing, like the existing data of pg_stat_io for consistency. The timings related to IOOBJECT_WAL show up if the GUC is enabled (disabled by default). Bump pgstats file version, due to the additions in IOObject and IOContext, impacting the amount of data written for the fixed-numbered IO stats kind in the pgstats file. Author: Nazir Bilal Yavuz Reviewed-by: Bertrand Drouvot, Nitin Jadhav, Amit Kapila, Michael Paquier, Melanie Plageman, Bharath Rupireddy Discussion: https://postgr.es/m/CAN55FZ3AiQ+ZMxUuXnBpd0Rrh1YhwJ5FudkHg=JU0P+-W8T4Vg@mail.gmail.com
* Fix typo in xlog.cMichael Paquier2025-02-03
| | | | "recovery" is not a verb. Introduced in 68cb5af46cd8.
* Allow changing autovacuum_max_workers without restarting.Nathan Bossart2025-01-06
| | | | | | | | | | | | | | | | | | | | | | | This commit introduces a new parameter named autovacuum_worker_slots that controls how many autovacuum worker slots to reserve during server startup. Modifying this new parameter's value does require a server restart, but it should typically be set to the upper bound of what you might realistically need to set autovacuum_max_workers. With that new parameter in place, autovacuum_max_workers can now be changed with a SIGHUP (e.g., pg_ctl reload). If autovacuum_max_workers is set higher than autovacuum_worker_slots, a WARNING is emitted, and the server will only start up to autovacuum_worker_slots workers at a given time. If autovacuum_max_workers is set to a value less than the number of currently-running autovacuum workers, the existing workers will continue running, but no new workers will be started until the number of running autovacuum workers drops below autovacuum_max_workers. Reviewed-by: Sami Imseih, Justin Pryzby, Robert Haas, Andres Freund, Yogesh Sharma Discussion: https://postgr.es/m/20240410212344.GA1824549%40nathanxps13
* Fix an assortment of spelling mistakes and typosDavid Rowley2025-01-02
| | | | | Author: Alexander Lakhin <exclusion@gmail.com> Discussion: https://postgr.es/m/5812a0b9-b0cf-4151-9a14-d9f00e4f2858@gmail.com
* Update copyright for 2025Bruce Momjian2025-01-01
| | | | Backpatch-through: 13
* Revert pg_wal_replay_wait() stored procedureAlexander Korotkov2024-11-04
| | | | | | | | | | | | | | | | This commit reverts 3c5db1d6b0, and subsequent improvements and fixes including 8036d73ae3, 867d396ccd, 3ac3ec580c, 0868d7ae70, 85b98b8d5a, 2520226c95, 014f9f34d2, e658038772, e1555645d7, 5035172e4a, 6cfebfe88b, 73da6b8d1b, and e546989a26. The reason for reverting is a set of remaining issues. Most notably, the stored procedure appears to need more effort than the utility statement to turn the backend into a "snapshot-less" state. This makes an approach to use stored procedures questionable. Catversion is bumped. Discussion: https://postgr.es/m/Zyhj2anOPRKtb0xW%40paquier.xyz
* Rename two functions that wake up other processesHeikki Linnakangas2024-11-01
| | | | | | | | | | | Instead of talking about setting latches, which is a pretty low-level mechanism, emphasize that they wake up other processes. This is in preparation for replacing Latches with a new abstraction. That's still work in progress, but this seems a little tidier anyway, so let's get this refactoring out of the way already. Discussion: https://www.postgresql.org/message-id/391abe21-413e-4d91-a650-b663af49500c%40iki.fi
* Use ProcNumbers instead of direct Latch pointers to address other procsHeikki Linnakangas2024-11-01
| | | | | | | | This is in preparation for replacing Latches with a new abstraction. That's still work in progress, but this seems a little tidier anyway, so let's get this refactoring out of the way already. Discussion: https://www.postgresql.org/message-id/391abe21-413e-4d91-a650-b663af49500c%40iki.fi
* Fix WAL_DEBUG buildPeter Eisentraut2024-10-28
| | | | | | broken by commit e18512c000e Reported-by: Peter Geoghegan <pg@bowt.ie>
* Remove unused #include's from backend .c filesPeter Eisentraut2024-10-27
| | | | | | | | as determined by IWYU These are mostly issues that are new since commit dbbca2cf299. Discussion: https://www.postgresql.org/message-id/flat/0df1d5b1-8ca8-4f84-93be-121081bde049%40eisentraut.org
* Move LSN waiting declarations and definitions to better placeAlexander Korotkov2024-10-24
| | | | | | | | | | | | | | | | | | | 3c5db1d6b implemented the pg_wal_replay_wait() stored procedure. Due to the patch development history, the implementation resided in src/backend/commands/waitlsn.c (src/include/commands/waitlsn.h for headers). 014f9f34d moved pg_wal_replay_wait() itself to src/backend/access/transam/xlogfuncs.c near to the WAL-manipulation functions. But most of the implementation stayed in place. The code in src/backend/commands/waitlsn.c has nothing to do with commands, but is related to WAL. So, this commit moves this code into src/backend/access/transam/xlogwait.c (src/include/access/xlogwait.h for headers). Reported-by: Peter Eisentraut Discussion: https://postgr.es/m/18c0fa64-0475-415e-a1bd-665d922c5201%40eisentraut.org Reviewed-by: Pavel Borisov
* Fix inconsistent reporting of checkpointer stats.Fujii Masao2024-10-02
| | | | | | | | | | | | | | | | | | | | | | | Previously, the pg_stat_checkpointer view and the checkpoint completion log message could show different numbers for buffers written during checkpoints. The view only counted shared buffers, while the log message included both shared and SLRU buffers, causing inconsistencies. This commit resolves the issue by updating both the view and the log message to separately report shared and SLRU buffers written during checkpoints. A new slru_written column is added to the pg_stat_checkpointer view to track SLRU buffers, while the existing buffers_written column now tracks only shared buffers. This change would help users distinguish between the two types of buffers, in the pg_stat_checkpointer view and the checkpoint complete log message, respectively. Bump catalog version. Author: Nitin Jadhav Reviewed-by: Bharath Rupireddy, Michael Paquier, Kyotaro Horiguchi, Robert Haas Reviewed-by: Andres Freund, vignesh C, Fujii Masao Discussion: https://postgr.es/m/CAMm1aWb18EpT0whJrjG+-nyhNouXET6ZUw0pNYYAe+NezpvsAA@mail.gmail.com
* Add num_done counter to the pg_stat_checkpointer view.Fujii Masao2024-09-30
| | | | | | | | | | | | | | | Checkpoints can be skipped when the server is idle. The existing num_timed and num_requested counters in pg_stat_checkpointer track both completed and skipped checkpoints, but there was no way to count only the completed ones. This commit introduces the num_done counter, which tracks only completed checkpoints, making it easier to see how many were actually performed. Bump catalog version. Author: Anton A. Melnikov Reviewed-by: Fujii Masao Discussion: https://postgr.es/m/9ea77f40-818d-4841-9dee-158ac8f6e690@oss.nttdata.com
* Minor cleanup related to pg_wal_replay_wait() procedureAlexander Korotkov2024-09-17
| | | | | | | | | | | | * Rename $node_standby1 to $node_standby in 043_wal_replay_wait.pl as there is only one standby. * Remove useless debug printing in 043_wal_replay_wait.pl. * Fix typo in one check description in 043_wal_replay_wait.pl. * Fix some wording in comments and documentation. Reported-by: Alexander Lakhin Discussion: https://postgr.es/m/1d7b08f2-64a2-77fb-c666-c9a74c68eeda%40gmail.com Reviewed-by: Alexander Lakhin
* Unify some error messages to ease work of translatorsMichael Paquier2024-09-04
| | | | | | | | | This commit updates a couple of error messages around control file data, GUCs and server settings, unifying to the same message where possible. This reduces the translation burden a bit. Author: Peter Smith Discussion: https://postgr.es/m/CAHut+Pv-kSN8SkxSdoHano_wPubqcg5789ejhCDZAcLFceBR-w@mail.gmail.com
* Apply more quoting to GUC names in messagesMichael Paquier2024-09-04
| | | | | | | | | This is a continuation of 17974ec25946. More quotes are applied to GUC names in error messages and hints, taking care of what seems to be all the remaining holes currently in the tree for the GUCs. Author: Peter Smith Discussion: https://postgr.es/m/CAHut+Pv-kSN8SkxSdoHano_wPubqcg5789ejhCDZAcLFceBR-w@mail.gmail.com
* Add const qualifiers to XLogRegister*() functionsPeter Eisentraut2024-09-03
| | | | | | | | Add const qualifiers to XLogRegisterData() and XLogRegisterBufData(). Several unconstify() calls can be removed. Reviewed-by: Aleksander Alekseev <aleksander@timescale.com> Discussion: https://www.postgresql.org/message-id/dd889784-9ce7-436a-b4f1-52e4a5e577bd@eisentraut.org
* Define PG_TBLSPC_DIR for path pg_tblspc/ in data folderMichael Paquier2024-09-03
| | | | | | | | | | | | | | Similarly to 2065ddf5e34c, this introduces a define for "pg_tblspc". This makes the style more consistent with the existing PG_STAT_TMP_DIR, for example. There is a difference with the other cases with the introduction of PG_TBLSPC_DIR_SLASH, required in two places for recovery and backups. Author: Bertrand Drouvot Reviewed-by: Ashutosh Bapat, Álvaro Herrera, Yugo Nagata, Michael Paquier Discussion: https://postgr.es/m/ZryVvjqS9SnV1GPP@ip-10-97-1-34.eu-west-3.compute.internal
* Implement pg_wal_replay_wait() stored procedureAlexander Korotkov2024-08-02
| | | | | | | | | | | | | | | | | | | | | | | | | | pg_wal_replay_wait() is to be used on standby and specifies waiting for the specific WAL location to be replayed. This option is useful when the user makes some data changes on primary and needs a guarantee to see these changes are on standby. The queue of waiters is stored in the shared memory as an LSN-ordered pairing heap, where the waiter with the nearest LSN stays on the top. During the replay of WAL, waiters whose LSNs have already been replayed are deleted from the shared memory pairing heap and woken up by setting their latches. pg_wal_replay_wait() needs to wait without any snapshot held. Otherwise, the snapshot could prevent the replay of WAL records, implying a kind of self-deadlock. This is why it is only possible to implement pg_wal_replay_wait() as a procedure working without an active snapshot, not a function. Catversion is bumped. Discussion: https://postgr.es/m/eb12f9b03851bb2583adab5df9579b4b%40postgrespro.ru Author: Kartyshov Ivan, Alexander Korotkov Reviewed-by: Michael Paquier, Peter Eisentraut, Dilip Kumar, Amit Kapila Reviewed-by: Alexander Lakhin, Bharath Rupireddy, Euler Taveira Reviewed-by: Heikki Linnakangas, Kyotaro Horiguchi
* Add redo LSN to pgstats filesMichael Paquier2024-08-02
| | | | | | | | | | | | | | | | This is used in the startup process to check that the pgstats file we are reading includes the redo LSN referring to the shutdown checkpoint where it has been written. The redo LSN in the pgstats file needs to match with what the control file has. This is intended to be used for an upcoming change that will extend the write of the stats file to happen during checkpoints, rather than only shutdown sequences. Bump PGSTAT_FILE_FORMAT_ID. Reviewed-by: Bertrand Drouvot Discussion: https://postgr.es/m/Zp8o6_cl0KSgsnvS@paquier.xyz
* Replace static buf with a stack-allocated one in ReadControlFileHeikki Linnakangas2024-07-30
| | | | | | | It's only used very locally within the function. Reviewed-by: Robert Haas Discussion: https://www.postgresql.org/message-id/7f86e06a-98c5-4ce3-8ec9-3885c8de0358@iki.fi
* Replace static buf with palloc in str_time()Heikki Linnakangas2024-07-30
| | | | | | | | | | The function is used only once in the startup process, so the leak into current memory context is harmless. This is a tiny step in making the server thread-safe. Reviewed-by: Robert Haas Discussion: https://www.postgresql.org/message-id/7f86e06a-98c5-4ce3-8ec9-3885c8de0358@iki.fi
* Wait for WAL summarization to catch up before creating .partial file.Robert Haas2024-07-26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When a standby is promoted, CleanupAfterArchiveRecovery() may decide to rename the final WAL file from the old timeline by adding ".partial" to the name. If WAL summarization is enabled and this file is renamed before its partial contents are summarized, WAL summarization breaks: the summarizer gets stuck at that point in the WAL stream and just errors out. To fix that, first make the startup process wait for WAL summarization to catch up before renaming the file. Generally, this should be quick, and if it's not, the user can shut off summarize_wal and try again. To make this fix work, also teach the WAL summarizer that after a promotion has occurred, no more WAL can appear on the previous timeline: previously, the WAL summarizer wouldn't switch to the new timeline until we actually started writing WAL there, but that meant that when the startup process was waiting for the WAL summarizer, it was waiting for an action that the summarizer wasn't yet prepared to take. In the process of fixing these bugs, I realized that the logic to wait for WAL summarization to catch up was spread out in a way that made it difficult to reuse properly, so this code refactors things to make it easier. Finally, add a test case that would have caught this bug and the previously-fixed bug that WAL summarization sometimes needs to back up when the timeline changes. Discussion: https://postgr.es/m/CA+TgmoZGEsZodXC4f=XZNkAeyuDmWTSkpkjCEOcF19Am0mt_OA@mail.gmail.com
* Get rid of a global variablePeter Eisentraut2024-07-23
| | | | | | | | bootstrap_data_checksum_version can just as easily be passed to where it is used via function arguments. Reviewed-by: Andres Freund <andres@anarazel.de> Discussion: https://www.postgresql.org/message-id/flat/e0a62134-83da-4ba4-8cdb-ceb0111c95ce@eisentraut.org
* Initialize wal_level in the initial checkpoint record.Robert Haas2024-07-22
| | | | | | As per Coverity and Tom Lane, commit 402b586d0 (back-patched to v17 as 2b5819e2b) forgot to initialize this new structure member in this code path.
* Do not summarize WAL if generated with wal_level=minimal.Robert Haas2024-07-18
| | | | | | | | | | | | | | | | | | | | | | | | | | To do this, we must include the wal_level in the first WAL record covered by each summary file; so add wal_level to struct Checkpoint and the payload of XLOG_CHECKPOINT_REDO and XLOG_END_OF_RECOVERY. This, in turn, requires bumping XLOG_PAGE_MAGIC and, since the Checkpoint is also stored in the control file, also PG_CONTROL_VERSION. It's not great to do that so late in the release cycle, but the alternative seems to ship v17 without robust protections against this scenario, which could result in corrupted incremental backups. A side effect of this patch is that, when a server with wal_level=replica is started with summarize_wal=on for the first time, summarization will no longer begin with the oldest WAL that still exists in pg_wal, but rather from the first checkpoint after that. This change should be harmless, because a WAL summary for a partial checkpoint cycle can never make an incremental backup possible when it would otherwise not have been. Report by Fujii Masao. Patch by me. Review and/or testing by Jakub Wartak and Fujii Masao. Discussion: http://postgr.es/m/6e30082e-041b-4e31-9633-95a66de76f5d@oss.nttdata.com
* Use safe string copy routineDaniel Gustafsson2024-07-02
| | | | | | | | | | | Using memcpy with strlen as the size parameter will not take the NULL terminator into account, relying instead on the destination buffer being properly initialized. Replace with strlcpy which is a safer alternative, and more in line with how we handle copying strings elsewhere. Author: Ranier Vilela <ranier.vf@gmail.com> Discussion: https://postgr.es/m/CAEudQApAsbLsQ+gGiw-hT+JwGhgogFa_=5NUkgFO6kOPxyNidQ@mail.gmail.com
* Prevent summarizer hang when summarize_wal turned off and back on.Robert Haas2024-06-28
| | | | | | | | | | | | | | | Before this commit, when the WAL summarizer started up or recovered from an error, it would resume summarization from wherever it left off. That was OK normally, but wrong if summarize_wal=off had been turned off temporary, allowing some WAL to be removed, and then turned back on again. In such cases, the WAL summarizer would simply hang forever. This commit changes the reinitialization sequence for WAL summarizer to rederive the starting position in the way we were already doing at initial startup, fixing the problem. Per report from Israel Barth Rubio. Reviewed by Tom Lane. Discussion: http://postgr.es/m/CA+TgmoYN6x=YS+FoFOS6=nr6=qkXZFWhdiL7k0oatGwug2hcuA@mail.gmail.com
* Fix MVCC bug with prepared xact with subxacts on standbyHeikki Linnakangas2024-06-27
| | | | | | | | | | | | | | | | | | We did not recover the subtransaction IDs of prepared transactions when starting a hot standby from a shutdown checkpoint. As a result, such subtransactions were considered as aborted, rather than in-progress. That would lead to hint bits being set incorrectly, and the subtransactions suddenly becoming visible to old snapshots when the prepared transaction was committed. To fix, update pg_subtrans with prepared transactions's subxids when starting hot standby from a shutdown checkpoint. The snapshots taken from that state need to be marked as "suboverflowed", so that we also check the pg_subtrans. Backport to all supported versions. Discussion: https://www.postgresql.org/message-id/6b852e98-2d49-4ca1-9e95-db419a2696e0@iki.fi
* Fix bugs in MultiXact truncationHeikki Linnakangas2024-06-26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 1. TruncateMultiXact() performs the SLRU truncations in a critical section. Deleting the SLRU segments calls ForwardSyncRequest(), which will try to compact the request queue if it's full (CompactCheckpointerRequestQueue()). That in turn allocates memory, which is not allowed in a critical section. Backtrace: TRAP: failed Assert("CritSectionCount == 0 || (context)->allowInCritSection"), File: "../src/backend/utils/mmgr/mcxt.c", Line: 1353, PID: 920981 postgres: autovacuum worker template0(ExceptionalCondition+0x6e)[0x560a501e866e] postgres: autovacuum worker template0(+0x5dce3d)[0x560a50217e3d] postgres: autovacuum worker template0(ForwardSyncRequest+0x8e)[0x560a4ffec95e] postgres: autovacuum worker template0(RegisterSyncRequest+0x2b)[0x560a50091eeb] postgres: autovacuum worker template0(+0x187b0a)[0x560a4fdc2b0a] postgres: autovacuum worker template0(SlruDeleteSegment+0x101)[0x560a4fdc2ab1] postgres: autovacuum worker template0(TruncateMultiXact+0x2fb)[0x560a4fdbde1b] postgres: autovacuum worker template0(vac_update_datfrozenxid+0x4b3)[0x560a4febd2f3] postgres: autovacuum worker template0(+0x3adf66)[0x560a4ffe8f66] postgres: autovacuum worker template0(AutoVacWorkerMain+0x3ed)[0x560a4ffe7c2d] postgres: autovacuum worker template0(+0x3b1ead)[0x560a4ffecead] postgres: autovacuum worker template0(+0x3b620e)[0x560a4fff120e] postgres: autovacuum worker template0(+0x3b3fbb)[0x560a4ffeefbb] postgres: autovacuum worker template0(+0x2f724e)[0x560a4ff3224e] /lib/x86_64-linux-gnu/libc.so.6(+0x27c8a)[0x7f62cc642c8a] /lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0x85)[0x7f62cc642d45] postgres: autovacuum worker template0(_start+0x21)[0x560a4fd16f31] To fix, bail out in CompactCheckpointerRequestQueue() without doing anything, if it's called in a critical section. That covers the above call path, as well as any other similar cases where RegisterSyncRequest might be called in a critical section. 2. After fixing that, another problem became apparent: Autovacuum process doing that truncation can deadlock with the checkpointer process. TruncateMultiXact() sets "MyProc->delayChkptFlags |= DELAY_CHKPT_START". If the sync request queue is full and cannot be compacted, the process will repeatedly sleep and retry, until there is room in the queue. However, if the checkpointer is trying to start a checkpoint at the same time, and is waiting for the DELAY_CHKPT_START processes to finish, the queue will never shrink. More concretely, the autovacuum process is stuck here: #0 0x00007fc934926dc3 in epoll_wait () from /lib/x86_64-linux-gnu/libc.so.6 #1 0x000056220b24348b in WaitEventSetWaitBlock (set=0x56220c2e4b50, occurred_events=0x7ffe7856d040, nevents=1, cur_timeout=<optimized out>) at ../src/backend/storage/ipc/latch.c:1570 #2 WaitEventSetWait (set=0x56220c2e4b50, timeout=timeout@entry=10, occurred_events=<optimized out>, occurred_events@entry=0x7ffe7856d040, nevents=nevents@entry=1, wait_event_info=wait_event_info@entry=150994949) at ../src/backend/storage/ipc/latch.c:1516 #3 0x000056220b243224 in WaitLatch (latch=<optimized out>, latch@entry=0x0, wakeEvents=wakeEvents@entry=40, timeout=timeout@entry=10, wait_event_info=wait_event_info@entry=150994949) at ../src/backend/storage/ipc/latch.c:538 #4 0x000056220b26cf46 in RegisterSyncRequest (ftag=ftag@entry=0x7ffe7856d0a0, type=type@entry=SYNC_FORGET_REQUEST, retryOnError=true) at ../src/backend/storage/sync/sync.c:614 #5 0x000056220af9db0a in SlruInternalDeleteSegment (ctl=ctl@entry=0x56220b7beb60 <MultiXactMemberCtlData>, segno=segno@entry=11350) at ../src/backend/access/transam/slru.c:1495 #6 0x000056220af9dab1 in SlruDeleteSegment (ctl=ctl@entry=0x56220b7beb60 <MultiXactMemberCtlData>, segno=segno@entry=11350) at ../src/backend/access/transam/slru.c:1566 #7 0x000056220af98e1b in PerformMembersTruncation (oldestOffset=<optimized out>, newOldestOffset=<optimized out>) at ../src/backend/access/transam/multixact.c:3006 #8 TruncateMultiXact (newOldestMulti=newOldestMulti@entry=3221225472, newOldestMultiDB=newOldestMultiDB@entry=4) at ../src/backend/access/transam/multixact.c:3201 #9 0x000056220b098303 in vac_truncate_clog (frozenXID=749, minMulti=<optimized out>, lastSaneFrozenXid=749, lastSaneMinMulti=3221225472) at ../src/backend/commands/vacuum.c:1917 #10 vac_update_datfrozenxid () at ../src/backend/commands/vacuum.c:1760 #11 0x000056220b1c3f76 in do_autovacuum () at ../src/backend/postmaster/autovacuum.c:2550 #12 0x000056220b1c2c3d in AutoVacWorkerMain (startup_data=<optimized out>, startup_data_len=<optimized out>) at ../src/backend/postmaster/autovacuum.c:1569 and the checkpointer is stuck here: #0 0x00007fc9348ebf93 in clock_nanosleep () from /lib/x86_64-linux-gnu/libc.so.6 #1 0x00007fc9348fe353 in nanosleep () from /lib/x86_64-linux-gnu/libc.so.6 #2 0x000056220b40ecb4 in pg_usleep (microsec=microsec@entry=10000) at ../src/port/pgsleep.c:50 #3 0x000056220afb43c3 in CreateCheckPoint (flags=flags@entry=108) at ../src/backend/access/transam/xlog.c:7098 #4 0x000056220b1c6e86 in CheckpointerMain (startup_data=<optimized out>, startup_data_len=<optimized out>) at ../src/backend/postmaster/checkpointer.c:464 To fix, add AbsorbSyncRequests() to the loops where the checkpointer waits for DELAY_CHKPT_START or DELAY_CHKPT_COMPLETE operations to finish. Backpatch to v14. Before that, SLRU deletion didn't call RegisterSyncRequest, which avoided this failure. I'm not sure if there are other similar scenarios on older versions, but we haven't had any such reports. Discussion: https://www.postgresql.org/message-id/ccc66933-31c1-4f6a-bf4b-45fef0d4f22e@iki.fi
* Revise GUC names quoting in messages againPeter Eisentraut2024-05-17
| | | | | | | | | | | | | | | After further review, we want to move in the direction of always quoting GUC names in error messages, rather than the previous (PG16) wildly mixed practice or the intermittent (mid-PG17) idea of doing this depending on how possibly confusing the GUC name is. This commit applies appropriate quotes to (almost?) all mentions of GUC names in error messages. It partially supersedes a243569bf65 and 8d9978a7176, which had moved things a bit in the opposite direction but which then were abandoned in a partial state. Author: Peter Smith <smithpb2250@gmail.com> Discussion: https://www.postgresql.org/message-id/flat/CAHut%2BPv-kSN8SkxSdoHano_wPubqcg5789ejhCDZAcLFceBR-w%40mail.gmail.com
* Fix an assortment of typosDavid Rowley2024-05-04
| | | | | Author: Alexander Lakhin Discussion: https://postgr.es/m/ae9f2fcb-4b24-5bb0-4240-efbbbd944ca1@gmail.com
* Revert: Implement pg_wal_replay_wait() stored procedureAlexander Korotkov2024-04-11
| | | | | | | This commit reverts 06c418e163, e37662f221, bf1e650806, 25f42429e2, ee79928441, and 74eaf66f98 per review by Heikki Linnakangas. Discussion: https://postgr.es/m/b155606b-e744-4218-bda5-29379779da1a%40iki.fi
* Add XLogCtl->logInsertResultAlvaro Herrera2024-04-07
| | | | | | | | | | | | | | | | | | This tracks the position of WAL that's been fully copied into WAL buffers by all processes emitting WAL. (For some reason we call that "WAL insertion"). This is updated using atomic monotonic advance during WaitXLogInsertionsToFinish, which is not when the insertions actually occur, but it's the only place where we know where have all the insertions have completed. This value is useful in WALReadFromBuffers, which can verify that callers don't try to read past what has been inserted. (However, more infrastructure is needed in order to actually use WAL after the flush point, since it could be lost.) The value is also useful in WaitXLogInsertionsToFinish() itself, since we can now exit quickly when all WAL has been already inserted, without even having to take any locks.
* Operate XLogCtl->log{Write,Flush}Result with atomicsAlvaro Herrera2024-04-05
| | | | | | | | | | | | | | | | | This removes the need to hold both the info_lck spinlock and WALWriteLock to update them. We use stock atomic write instead, with WALWriteLock held. Readers can use atomic read, without any locking. This allows for some code to be reordered: some places were a bit contorted to avoid repeated spinlock acquisition, but that's no longer a concern, so we can turn them to more natural coding. Some further changes are possible (maybe to performance wins), but in this commit I did rather minimal ones only, to avoid increasing the blast radius. Reviewed-by: Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com> Reviewed-by: Jeff Davis <pgsql@j-davis.com> Reviewed-by: Andres Freund <andres@anarazel.de> (earlier versions) Discussion: https://postgr.es/m/20200831182156.GA3983@alvherre.pgsql