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* Fix handling of multi-column BRIN indexesTomas Vondra2023-02-19
| | | | | | | | | | | | | | When evaluating clauses on multiple scan keys of a multi-column BRIN index, we can stop processing as soon as we find a scan key eliminating the range, and the range should not be added to tbe bitmap. That's how it worked before 14, but since a681e3c107a the code treated the range as matching if it matched at least the last scan key. Backpatch to 14, where this code was introduced. Backpatch-through: 14 Discussion: https://postgr.es/m/ebc18613-125e-60df-7520-fcbe0f9274fc%40enterprisedb.com
* Un-revert "Disable STARTUP_PROGRESS_TIMEOUT in standby mode."Robert Haas2023-02-10
| | | | | | | | | This reverts commit 1eadfbdd7eb0679ba8d45787aa8b2f06e76de20a and thus reinstates commit 98e7234242a652497c99d4d0d6f2bf9a75d4e921. It's a better time to commit this now that the release is over. Discussion: http://postgr.es/m/3509384.1675878203@sss.pgh.pa.us
* Revert "Disable STARTUP_PROGRESS_TIMEOUT in standby mode."Robert Haas2023-02-06
| | | | | | | | | This reverts commit 98e7234242a652497c99d4d0d6f2bf9a75d4e921. I forgot that we're about to wrap a release, and this fix isn't critical enough to justify committing it right before we wrap a release. Discussion: http://postgr.es/m/2676424.1675700113@sss.pgh.pa.us
* Disable STARTUP_PROGRESS_TIMEOUT in standby mode.Robert Haas2023-02-06
| | | | | | | | | | | | | In standby mode, we don't actually report progress of recovery, but up until now, startup_progress_timeout_handler() nevertheless got called every log_startup_progress_interval seconds. That's an unnecessary expense, so avoid it. Report by Thomas Munro. Patch by Bharath Rupireddy, reviewed by Simon Riggs, Thomas Munro, and me. Back-patch to v15, where the problem was introduced. Discussion: https://www.postgresql.org/message-id/CA%2BhUKGKCHSffAj8zZJKJvNX7ygnQFxVD6wm1d-2j3fVw%2BMafPQ%40mail.gmail.com
* Log the correct ending timestamp in recovery_target_xid mode.Tom Lane2023-01-19
| | | | | | | | | | | | | | | | When ending recovery based on recovery_target_xid matching with recovery_target_inclusive = off, we printed an incorrect timestamp (always 2000-01-01) in the "recovery stopping before ... transaction" log message. This is a consequence of sloppy refactoring in c945af80c: the code to fetch recordXtime out of the commit/abort record used to be executed unconditionally, but it was changed to get called only in the RECOVERY_TARGET_TIME case. We need only flip the order of operations to restore the intended behavior. Per report from Torsten Förtsch. Back-patch to all supported branches. Discussion: https://postgr.es/m/CAKkG4_kUevPqbmyOfLajx7opAQk6Cvwkvx0HRcFjSPfRPTXanA@mail.gmail.com
* Fix typos in comments, code and documentationMichael Paquier2023-01-03
| | | | | | | | | | While on it, newlines are removed from the end of two elog() strings. The others are simple grammar mistakes. One comment in pg_upgrade referred incorrectly to sequences since a7e5457. Author: Justin Pryzby Discussion: https://postgr.es/m/20221230231257.GI1153@telsasoft.com Backpatch-through: 11
* Fix assert in BRIN build_distancesTomas Vondra2022-12-30
| | | | | | | | | | | | | | | | | | | | | When brin_minmax_multi_union merges summaries, we may end up with just a single range after merge_overlapping_ranges. The summaries may contain just one range each, and they may overlap (or be exactly the same). With a single range there's no distance to calculate, but we happen to call build_distances anyway - which is fine, we don't calculate the distance in this case, except that with asserts this failed due to a check there are at least two ranges. The assert is unnecessarily strict, so relax it a bit and bail out if there's just a single range. The relaxed assert would be enough, but this way we don't allocate unnecessary memory for distance. Backpatch to 14, where minmax-multi opclasses were introduced. Reported-by: Jaime Casanova Backpatch-through: 14 Discussion: https://postgr.es/m/YzVA55qS0hgz8P3r@ahch-to
* Rethink handling of [Prevent|Is]InTransactionBlock in pipeline mode.Tom Lane2022-12-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commits f92944137 et al. made IsInTransactionBlock() set the XACT_FLAGS_NEEDIMMEDIATECOMMIT flag before returning "false", on the grounds that that kept its API promises equivalent to those of PreventInTransactionBlock(). This turns out to be a bad idea though, because it allows an ANALYZE in a pipelined series of commands to cause an immediate commit, which is unexpected. Furthermore, if we return "false" then we have another issue, which is that ANALYZE will decide it's allowed to do internal commit-and-start-transaction sequences, thus possibly unexpectedly committing the effects of previous commands in the pipeline. To fix the latter situation, invent another transaction state flag XACT_FLAGS_PIPELINING, which explicitly records the fact that we have executed some extended-protocol command and not yet seen a commit for it. Then, require that flag to not be set before allowing InTransactionBlock() to return "false". Having done that, we can remove its setting of NEEDIMMEDIATECOMMIT without fear of causing problems. This means that the API guarantees of IsInTransactionBlock now diverge from PreventInTransactionBlock, which is mildly annoying, but it seems OK given the very limited usage of IsInTransactionBlock. (In any case, a caller preferring the old behavior could always set NEEDIMMEDIATECOMMIT for itself.) For consistency also require XACT_FLAGS_PIPELINING to not be set in PreventInTransactionBlock. This too is meant to prevent commands such as CREATE DATABASE from silently committing previous commands in a pipeline. Per report from Peter Eisentraut. As before, back-patch to all supported branches (which sadly no longer includes v10). Discussion: https://postgr.es/m/65a899dd-aebc-f667-1d0a-abb89ff3abf8@enterprisedb.com
* Fix memory leak for hashing with nondeterministic collations.Jeff Davis2022-12-01
| | | | | | | Backpatch through 12, where nondeterministic collations were introduced (5e1963fb76). Backpatch-through: 12
* Improve heuristics for compressing the KnownAssignedXids array.Tom Lane2022-11-29
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Previously, we'd compress only when the active range of array entries reached Max(4 * PROCARRAY_MAXPROCS, 2 * pArray->numKnownAssignedXids). If max_connections is large, the first term could result in not compressing for a long time, resulting in much wastage of cycles in hot-standby backends scanning the array to take snapshots. Get rid of that term, and just bound it to 2 * pArray->numKnownAssignedXids. That however creates the opposite risk, that we might spend too much effort compressing. Hence, consider compressing only once every 128 commit records. (This frequency was chosen by benchmarking. While we only tried one benchmark scenario, the results seem stable over a fairly wide range of frequencies.) Also, force compression when processing RecoveryInfo WAL records (which should be infrequent); the old code could perform compression then, but would do so only after the same array-range check as for the transaction-commit path. Also, opportunistically run compression if the startup process is about to wait for WAL, though not oftener than once a second. This should prevent cases where we waste lots of time by leaving the array not-compressed for long intervals due to low WAL traffic. Lastly, add a simple check to keep us from uselessly compressing when the array storage is already compact. Back-patch, as the performance problem is worse in pre-v14 branches than in HEAD. Simon Riggs and Michail Nikolaev, with help from Tom Lane and Andres Freund. Discussion: https://postgr.es/m/CALdSSPgahNUD_=pB_j=1zSnDBaiOtqVfzo8Ejt5J_k7qZiU1Tw@mail.gmail.com
* Make multixact error message more explicitAlvaro Herrera2022-11-24
| | | | | | | | | | | | | | There are recent reports involving a very old error message that we have no history of hitting -- perhaps a recently introduced bug. Improve the error message in an attempt to improve our chances of investigating the bug. Per reports from Dimos Stamatakis and Bob Krier. Backpatch to 11. Discussion: https://postgr.es/m/CO2PR0801MB2310579F65529380A4E5EDC0E20A9@CO2PR0801MB2310.namprd08.prod.outlook.com Discussion: https://postgr.es/m/17518-04e368df5ad7f2ee@postgresql.org
* Fix cleanup lock acquisition in SPLIT_ALLOCATE_PAGE replay.Amit Kapila2022-11-14
| | | | | | | | | | | | | | | | During XLOG_HASH_SPLIT_ALLOCATE_PAGE replay, we were checking for a cleanup lock on the new bucket page after acquiring an exclusive lock on it and raising a PANIC error on failure. However, it is quite possible that checkpointer can acquire the pin on the same page before acquiring a lock on it, and then the replay will lead to an error. So instead, directly acquire the cleanup lock on the new bucket page during XLOG_HASH_SPLIT_ALLOCATE_PAGE replay operation. Reported-by: Andres Freund Author: Robert Haas Reviewed-By: Amit Kapila, Andres Freund, Vignesh C Backpatch-through: 11 Discussion: https://postgr.es/m/20220810022617.fvjkjiauaykwrbse@awork3.anarazel.de
* Fix theoretical torn page hazard.Jeff Davis2022-11-11
| | | | | | | | | | | | | | | | | | | | | | | | The original report was concerned with a possible inconsistency between the heap and the visibility map, which I was unable to confirm. The concern has been retracted. However, there did seem to be a torn page hazard when using checksums. By not setting the heap page LSN during redo, the protections of minRecoveryPoint were bypassed. Fixed, along with a misleading comment. It may have been impossible to hit this problem in practice, because it would require a page tear between the checksum and the flags, so I am marking this as a theoretical risk. But, as discussed, it did violate expectations about the page LSN, so it may have other consequences. Backpatch to all supported versions. Reported-by: Konstantin Knizhnik Reviewed-by: Konstantin Knizhnik Discussion: https://postgr.es/m/fed17dac-8cb8-4f5b-d462-1bb4908c029e@garret.ru Backpatch-through: 11
* Fix comment of SimpleLruInit() in slru.cMichael Paquier2022-11-10
| | | | | | | | | | sync_handler was not mentioned in the comment block of the function. Oversight in dee663f. Author: Aleksander Alekseev Discussion: https://postgr.es/m/CAJ7c6TPUd9BwNY47TtMxaijLHSbyHNdhu=kvbGnvO_bi+oC6_Q@mail.gmail.com Backpatch-through: 14
* Doc: add comments about PreventInTransactionBlock/IsInTransactionBlock.Tom Lane2022-11-09
| | | | | | | | | | | | | Add a little to the header comments for these functions to make it clearer what guarantees about commit behavior are provided to callers. (See commit f92944137 for context.) Although this is only a comment change, it's really documentation aimed at authors of extensions, so it seems appropriate to back-patch. Yugo Nagata and Tom Lane, per further discussion of bug #17434. Discussion: https://postgr.es/m/17434-d9f7a064ce2a88a3@postgresql.org
* Fix ordering issue with WAL operations in GIN fast insert pathMichael Paquier2022-10-26
| | | | | | | | | | | | | | | | | | | | | | | | Contrary to what is documented in src/backend/access/transam/README, ginHeapTupleFastInsert() had a few ordering issues with the way it does its WAL operations when inserting items in its fast path. First, when using a separate list, XLogBeginInsert() was being always called before START_CRIT_SECTION(), and in this case a second thing was wrong when merging lists, as an exclusive lock was taken on the tail page *before* calling XLogBeginInsert(). Finally, when inserting items into a tail page, the order of XLogBeginInsert() and START_CRIT_SECTION() was reversed. This commit addresses all these issues by moving the calls of XLogBeginInsert() after all the pages logged are locked and pinned, within a critical section. This has been applied first only on HEAD as of 56b6625, but as per discussion with Tom Lane and Álvaro Herrera, a backpatch is preferred to keep all the branches consistent and to respect the transam's README where we can. Author: Matthias van de Meent, Zhang Mingli Discussion: https://postgr.es/m/CAEze2WhL8uLMqynnnCu1LAPwxD5RKEo0nHV+eXGg_N6ELU88HQ@mail.gmail.com Backpatch-through: 10
* Rename SetSingleFuncCall() to InitMaterializedSRF()Michael Paquier2022-10-18
| | | | | | | | | | | | | | | | | | Per discussion, the existing routine name able to initialize a SRF function with materialize mode is unpopular, so rename it. Equally, the flags of this function are renamed, as of: - SRF_SINGLE_USE_EXPECTED -> MAT_SRF_USE_EXPECTED_DESC - SRF_SINGLE_BLESS -> MAT_SRF_BLESS The previous function and flags introduced in 9e98583 are kept around for compatibility purposes, so as any extension code already compiled with v15 continues to work as-is. The declarations introduced here for compatibility will be removed from HEAD in a follow-up commit. The new names have been suggested by Andres Freund and Melanie Plageman. Discussion: https://postgr.es/m/20221013194820.ciktb2sbbpw7cljm@awork3.anarazel.de Backpatch-through: 15
* doc: Fix some grammar and typosMichael Paquier2022-10-01
| | | | | | | | This fixes some areas related to logical replication and custom RMGRs. Author: Ekaterina Kiryanova Discussion: https://postgr.es/m/fa4773f1-1396-384a-bcd7-85b5e013f399@postgrespro.ru Backpatch-through: 15
* Avoid improbable PANIC during heap_update, redux.Tom Lane2022-09-30
| | | | | | | | | | | | | | | | | | | | Commit 34f581c39 intended to ensure that RelationGetBufferForTuple would acquire a visibility-map page pin in case the otherBuffer's all-visible bit had become set since we last had lock on that page. But I missed a case: when we're extending the relation, VM concerns were dealt with only in the relatively-less-likely case that we fail to conditionally lock the otherBuffer. I think I'd believed that we couldn't need to worry about it if the conditional lock succeeds, which is true for the target buffer; but the otherBuffer was unlocked for awhile so its bit might be set anyway. So we need to do the GetVisibilityMapPins dance, and then also recheck the page's free space, in both cases. Per report from Jaime Casanova. Back-patch to v12 as the previous patch was (although there's still no evidence that the bug is reachable pre-v14). Discussion: https://postgr.es/m/E1lWLjP-00006Y-Ml@gemulon.postgresql.org
* Message style improvementsPeter Eisentraut2022-09-24
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* Fix race condition where heap_delete() fails to pin VM page.Jeff Davis2022-09-22
| | | | | | | | | | Similar to 5f12bc94dc, the code must re-check PageIsAllVisible() after buffer lock is re-acquired. Backpatching to the same version, 12. Discussion: https://postgr.es/m/CAEP4nAw9jYQDKd_5Y+-s2E4YiUJq1vqiikFjYGpLShtp-K3gag@mail.gmail.com Reported-by: Robins Tharakan Reviewed-by: Robins Tharakan Backpatch-through: 12
* Clear ps display of startup process at the end of recoveryMichael Paquier2022-09-22
| | | | | | | | | | | | | | | | | If the ps display is not cleared at this point, the process could continue displaying "recovering NNN" even if handling end-of-recovery steps. df9274a has tackled that by providing some information with the end-of-recovery checkpoint but 7ff23c6 has nullified the effect of the first commit. Per a suggestion from Justin, just clear the ps display when we are done with recovery, so as no incorrect information is displayed. This may get extended in the future, but for now restore the pre-7ff23c6 behavior. Author: Justin Prysby Discussion: https://postgr.es/m/20220913223954.GU31833@telsasoft.com Backpatch-through: 15
* Suppress variable-set-but-not-used warnings from clang 15.Tom Lane2022-09-20
| | | | | | | | | | | | | | | | | | | | | | | | clang 15+ will issue a set-but-not-used warning when the only use of a variable is in autoincrements (e.g., "foo++;"). That's perfectly sensible, but it detects a few more cases that we'd not noticed before. Silence the warnings with our usual methods, such as PG_USED_FOR_ASSERTS_ONLY, or in one case by actually removing a useless variable. One thing that we can't nicely get rid of is that with %pure-parser, Bison emits "yynerrs" as a local variable that falls foul of this warning. To silence those, I inserted "(void) yynerrs;" in the top-level productions of affected grammars. Per recently-established project policy, this is a candidate for back-patching into out-of-support branches: it suppresses annoying compiler warnings but changes no behavior. Hence, back-patch to 9.5, which is as far as these patches go without issues. (A preliminary check shows that the prior branches need some other set-but-not-used cleanups too, so I'll leave them for another day.) Discussion: https://postgr.es/m/514615.1663615243@sss.pgh.pa.us
* Reset InstallXLogFileSegmentActive after walreceiver self-initiated exit.Noah Misch2022-09-15
| | | | | | | | | | | | | After commit cc2c7d65fc27e877c9f407587b0b92d46cd6dd16 added this flag, failure to reset it caused assertion failures. In non-assert builds, it made the system fail to achieve the objectives listed in that commit; chiefly, we might emit a spurious log message. Back-patch to v15, where that commit first appeared. Bharath Rupireddy and Kyotaro Horiguchi. Reviewed by Dilip Kumar, Nathan Bossart and Michael Paquier. Reported by Dilip Kumar. Discussion: https://postgr.es/m/CAFiTN-sE3ry=ycMPVtC+Djw4Fd7gbUGVv_qqw6qfzp=JLvqT3g@mail.gmail.com
* Don't reference out-of-bounds array elements in brin_minmax_multi.cDavid Rowley2022-09-13
| | | | | | | | | | | | | | | | | | The primary fix here is to fix has_matching_range() so it does not reference ranges->values[-1] when nranges == 0. Similar problems existed in AssertCheckRanges() too. It does not look like any of these problems could lead to a crash as the array in question is at the end of the Ranges struct, and values[-1] is memory that belongs to other fields in the struct. However, let's get rid of these rather unsafe coding practices. In passing, I (David) adjusted some comments to try to make it more clear what some of the fields are for in the Ranges struct. I had to study the code to find out what nsorted was for as I couldn't tell from the comments. Author: Ranier Vilela Discussion: https://postgr.es/m/CAEudQAqJQzPitufX-jR=YUbJafpCDAKUnwgdbX_MzSc93wuvdw@mail.gmail.com Backpatch-through: 14, where multi-range brin was added.
* Add more error context to RestoreBlockImage() and consume itMichael Paquier2022-09-09
| | | | | | | | | | | | | | | | | | | | | | | | | | | On failure in restoring a block image, no details were provided, while it is possible to see failure with an inconsistent record state, a failure in processing decompression or a failure in decompression because a build does not support this option. RestoreBlockImage() is used in two code paths in the backend code, during recovery and when checking a page consistency after applying masking, and both places are changed to consume the error message produced by the internal routine when it returns a false status. All the error messages are reported under ERRCODE_INTERNAL_ERROR, that gets used also when attempting to access a page compressed by a method not supported by the build attempting the decompression. This is something that can happen in core when doing physical replication with primary and standby using inconsistent build options, for example. This routine is available since 2c03216d and it has never provided any context about the error happening when it failed. This change is justified even more after 57aa5b2, that introduced compression of FPWs in WAL. Reported-by: Justin Prysby Author: Michael Paquier Discussion: https://postgr.es/m/20220905002320.GD31833@telsasoft.com Backpatch-through: 15
* Fix recovery_prefetch with low maintenance_io_concurrency.Thomas Munro2022-09-08
| | | | | | | | | | | | | | | | | | | | | | | | | | | We should process completed IOs *before* trying to start more, so that it is always possible to decode one more record when the decoded record queue is empty, even if maintenance_io_concurrency is set so low that a single earlier WAL record might have saturated the IO queue. That bug was hidden because the effect of maintenance_io_concurrency was arbitrarily clamped to be at least 2. Fix the ordering, and also remove that clamp. We need a special case for 0, which is now treated the same as recovery_prefetch=off, but otherwise the number is used directly. This allows for testing with 1, which would have made the problem obvious in simple test scenarios. Also add an explicit error message for missing contrecords. It was a bit strange that we didn't report an error already, and became a latent bug with prefetching, since the internal state that tracks aborted contrecords would not survive retrying, as revealed by 026_overwrite_contrecord.pl with this adjustment. Reporting an error prevents that. Back-patch to 15. Reported-by: Justin Pryzby <pryzby@telsasoft.com> Reviewed-by: Kyotaro Horiguchi <horikyota.ntt@gmail.com> Discussion: https://postgr.es/m/20220831140128.GS31833%40telsasoft.com
* Fix cache invalidation bug in recovery_prefetch.Thomas Munro2022-09-03
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | XLogPageRead() can retry internally after a pread() system call has succeeded, in the case of short reads, and page validation failures while in standby mode (see commit 0668719801). Due to an oversight in commit 3f1ce973, these cases could leave stale data in the internal cache of xlogreader.c without marking it invalid. The main defense against stale cached data on failure to read a page was in the error handling path of the calling function ReadPageInternal(), but that wasn't quite enough for errors handled internally by XLogPageRead()'s retry loop if we then exited with XLREAD_WOULDBLOCK. 1. ReadPageInternal() now marks the cache invalid before calling the page_read callback, by setting state->readLen to 0. It'll be set to a non-zero value only after a successful read. It'll stay valid as long as the caller requests data in the cached range. 2. XLogPageRead() no long performs internal retries while reading ahead. While such retries should work, the general philosophy is that we should give up prefetching if anything unusual happens so we can handle it when recovery catches up, to reduce the complexity of the system. Let's do that here too. 3. While here, a new function XLogReaderResetError() improves the separation between xlogrecovery.c and xlogreader.c, where the former previously clobbered the latter's internal error buffer directly. The new function makes this more explicit, and also clears a related flag, without which a standby would needlessly retry in the outer function. Thanks to Noah Misch for tracking down the conditions required for a rare build farm failure in src/bin/pg_ctl/t/003_promote.pl, and providing a reproducer. Back-patch to 15. Reported-by: Noah Misch <noah@leadboat.com> Discussion: https://postgr.es/m/20220807003627.GA4168930%40rfd.leadboat.com
* Prevent WAL corruption after a standby promotion.Robert Haas2022-08-29
| | | | | | | | | | | | | | | | | | | | | | | | | | | When a PostgreSQL instance performing archive recovery but not using standby mode is promoted, and the last WAL segment that it attempted to read ended in a partial record, the previous code would create invalid WAL on the new timeline. The WAL from the previously timeline would be copied to the new timeline up until the end of the last valid record, but instead of beginning to write WAL at immediately afterwards, the promoted server would write an overwrite contrecord at the beginning of the next segment. The end of the previous segment would be left as all-zeroes, resulting in failures if anything tried to read WAL from that file. The root of the issue is that ReadRecord() decides whether to set abortedRecPtr and missingContrecPtr based on the value of StandbyMode, but ReadRecord() switches to a new timeline based on the value of ArchiveRecoveryRequested. We shouldn't try to write an overwrite contrecord if we're switching to a new timeline, so change the test in ReadRecod() to check ArchiveRecoveryRequested instead. Code fix by Dilip Kumar. Comments by me incorporating suggested language from Álvaro Herrera. Further review from Kyotaro Horiguchi and Sami Imseih. Discussion: http://postgr.es/m/CAFiTN-t7umki=PK8dT1tcPV=mOUe2vNhHML6b3T7W7qqvvajjg@mail.gmail.com Discussion: http://postgr.es/m/FB0DEA0B-E14E-43A0-811F-C1AE93D00FF3%40amazon.com
* Fix code comments still referring to pg_start/stop_backup()Michael Paquier2022-08-24
| | | | | | | | | pg_start_backup() and pg_stop_backup() have been respectively renamed to pg_backup_start() and pg_backup_stop() as of 39969e2, but a few comments did not get the call. Reviewed-by: Kyotaro Horiguchi, David Steele Discussion: https://postgr.es/m/YrqGlj1+4DF3dbZ/@paquier.xyz
* Fix assert in logicalmsg_descTomas Vondra2022-08-17
| | | | | | | | | | | The assert, introduced by 9f1cf97bb5, is intended to check if the prefix is terminated by a \0 byte, but it has two flaws. Firstly, prefix_size includes the \0 byte, so prefix[prefix_size] points to the byte after the null byte. Secondly, the check ensures the byte is not equal \0, while it should be checking the opposite. Backpatch-through: 14 Discussion: https://postgr.es/m/b99b6101-2f14-3796-3dfa-4a6cd7d4326d@enterprisedb.com
* Move basebackup code to new directory src/backend/backupRobert Haas2022-08-10
| | | | | | Reviewed by David Steele and Justin Pryzby Discussion: http://postgr.es/m/CA+TgmoafqboATDSoXHz8VLrSwK_MDhjthK4hEpYjqf9_1Fmczw%40mail.gmail.com
* BRIN: mask BRIN_EVACUATE_PAGE for WAL consistency checkingAlvaro Herrera2022-08-05
| | | | | | | | | | | | | | | | That bit is unlogged and therefore it's wrong to consider it in WAL page comparison. Add a test that tickles the case, as branch testing technology allows. This has been a problem ever since wal consistency checking was introduced (commit a507b86900f6 for pg10), so backpatch to all supported branches. Author: 王海洋 (Haiyang Wang) <wanghaiyang.001@bytedance.com> Reviewed-by: Kyotaro Horiguchi <horikyota.ntt@gmail.com> Discussion: https://postgr.es/m/CACciXAD2UvLMOhc4jX9VvOKt7DtYLr3OYRBhvOZ-jRxtzc_7Jg@mail.gmail.com Discussion: https://postgr.es/m/CACciXADOfErX9Bx0nzE_SkdfXr6Bbpo5R=v_B6MUTEYW4ya+cg@mail.gmail.com
* Fix replay of create database records on standbyAlvaro Herrera2022-07-28
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Crash recovery on standby may encounter missing directories when replaying database-creation WAL records. Prior to this patch, the standby would fail to recover in such a case; however, the directories could be legitimately missing. Consider the following sequence of commands: CREATE DATABASE DROP DATABASE DROP TABLESPACE If, after replaying the last WAL record and removing the tablespace directory, the standby crashes and has to replay the create database record again, crash recovery must be able to continue. A fix for this problem was already attempted in 49d9cfc68bf4, but it was reverted because of design issues. This new version is based on Robert Haas' proposal: any missing tablespaces are created during recovery before reaching consistency. Tablespaces are created as real directories, and should be deleted by later replay. CheckRecoveryConsistency ensures they have disappeared. The problems detected by this new code are reported as PANIC, except when allow_in_place_tablespaces is set to ON, in which case they are WARNING. Apart from making tests possible, this gives users an escape hatch in case things don't go as planned. Author: Kyotaro Horiguchi <horikyota.ntt@gmail.com> Author: Asim R Praveen <apraveen@pivotal.io> Author: Paul Guo <paulguo@gmail.com> Reviewed-by: Anastasia Lubennikova <lubennikovaav@gmail.com> (older versions) Reviewed-by: Fujii Masao <masao.fujii@oss.nttdata.com> (older versions) Reviewed-by: Michaël Paquier <michael@paquier.xyz> Diagnosed-by: Paul Guo <paulguo@gmail.com> Discussion: https://postgr.es/m/CAEET0ZGx9AvioViLf7nbR_8tH9-=27DN5xWJ2P9-ROH16e4JUA@mail.gmail.com
* Force immediate commit after CREATE DATABASE etc in extended protocol.Tom Lane2022-07-26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We have a few commands that "can't run in a transaction block", meaning that if they complete their processing but then we fail to COMMIT, we'll be left with inconsistent on-disk state. However, the existing defenses for this are only watertight for simple query protocol. In extended protocol, we didn't commit until receiving a Sync message. Since the client is allowed to issue another command instead of Sync, we're in trouble if that command fails or is an explicit ROLLBACK. In any case, sitting in an inconsistent state while waiting for a client message that might not come seems pretty risky. This case wasn't reachable via libpq before we introduced pipeline mode, but it's always been an intended aspect of extended query protocol, and likely there are other clients that could reach it before. To fix, set a flag in PreventInTransactionBlock that tells exec_execute_message to force an immediate commit. This seems to be the approach that does least damage to existing working cases while still preventing the undesirable outcomes. While here, add some documentation to protocol.sgml that explicitly says how to use pipelining. That's latent in the existing docs if you know what to look for, but it's better to spell it out; and it provides a place to document this new behavior. Per bug #17434 from Yugo Nagata. It's been wrong for ages, so back-patch to all supported branches. Discussion: https://postgr.es/m/17434-d9f7a064ce2a88a3@postgresql.org
* Remove unnecessary Windows-specific basebackup code.Thomas Munro2022-07-22
| | | | | | | | | | | | | | | | | Commit c6f2f016 added an explicit check for a Windows "junction point". That turned out to be needed only because get_dirent_type() was busted on Windows. It's been fixed by commit 9d3444dc, so remove it. Add a TAP-test to demonstrate that in-place tablespaces are copied by pg_basebackup. This exercises the codepath that would fail before c6f2f016 on Windows, and shows that it still doesn't fail now that we're using get_dirent_type() on both Windows and Unix. Back-patch to 15, where in-place tablespaces arrived and caused this problem (ie directories where previously only symlinks were expected). Reviewed-by: Michael Paquier <michael@paquier.xyz> Discussion: https://postgr.es/m/CA%2BhUKGLzLK4PUPx0_AwXEWXOYAejU%3D7XpxnYE55Y%2Be7hB2N3FA%40mail.gmail.com
* Fix assertion failure and segmentation fault in backup code.Fujii Masao2022-07-20
| | | | | | | | | | | | | | | | | | | | | | When a non-exclusive backup is canceled, do_pg_abort_backup() is called and resets some variables set by pg_backup_start (pg_start_backup in v14 or before). But previously it forgot to reset the session state indicating whether a non-exclusive backup is in progress or not in this session. This issue could cause an assertion failure when the session running BASE_BACKUP is terminated after it executed pg_backup_start and pg_backup_stop (pg_stop_backup in v14 or before). Also it could cause a segmentation fault when pg_backup_stop is called after BASE_BACKUP in the same session is canceled. This commit fixes the issue by making do_pg_abort_backup reset that session state. Back-patch to all supported branches. Author: Fujii Masao Reviewed-by: Kyotaro Horiguchi, Masahiko Sawada, Michael Paquier, Robert Haas Discussion: https://postgr.es/m/3374718f-9fbf-a950-6d66-d973e027f44c@oss.nttdata.com
* Overload index_form_tuple to allow the memory context to be suppliedDavid Rowley2022-07-07
| | | | | | | | | | | | | | | | | | | | | | | 40af10b57 changed things so we make use of a generation memory context for storing tuples to be sorted by tuplesort.c. That change does not play nicely with the changes made in 9f03ca915 (back in 2014). That commit changed things so that index_form_tuple() is called while switched into the tuplestore's tuplecontext. In order to fetch the tuple from the index, index_form_tuple() must do various memory allocations which are unrelated to the storage of the final returned tuple. Although all of these allocations are pfree'd, the fact that we now use a generation context means that the memory for these pfree'd allocations won't be used again by any other allocation due to generation.c's lack of freelists. This could result in sorts used for building indexes exceeding maintenance_work_mem by a very large amount. Here we fix it so we no longer allocate anything apart from the tuple itself into the generation context by adding a new version of index_form_tuple named index_form_tuple_context, which can be called to specify the MemoryContext to allocate the tuple into. Discussion: https://postgr.es/m/CAApHDvrHQkiFRHiGiAS-LMOvJN-eK-s762=tVzBz8ZqUea-a_A@mail.gmail.com Backpatch-through: 15, where 40af10b57 was added.
* pgindent run prior to branching v15.Tom Lane2022-06-30
| | | | pgperltidy and reformat-dat-files too. Not many changes.
* Fix visibility check when XID is committed in CLOG but not in procarray.Heikki Linnakangas2022-06-27
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | TransactionIdIsInProgress had a fast path to return 'false' if the single-item CLOG cache said that the transaction was known to be committed. However, that was wrong, because a transaction is first marked as committed in the CLOG but doesn't become visible to others until it has removed its XID from the proc array. That could lead to an error: ERROR: t_xmin is uncommitted in tuple to be updated or for an UPDATE to go ahead without blocking, before the previous UPDATE on the same row was made visible. The window is usually very short, but synchronous replication makes it much wider, because the wait for synchronous replica happens in that window. Another thing that makes it hard to hit is that it's hard to get such a commit-in-progress transaction into the single item CLOG cache. Normally, if you call TransactionIdIsInProgress on such a transaction, it determines that the XID is in progress without checking the CLOG and without populating the cache. One way to prime the cache is to explicitly call pg_xact_status() on the XID. Another way is to use a lot of subtransactions, so that the subxid cache in the proc array is overflown, making TransactionIdIsInProgress rely on pg_subtrans and CLOG checks. This has been broken ever since it was introduced in 2008, but the race condition is very hard to hit, especially without synchronous replication. There were a couple of reports of the error starting from summer 2021, but no one was able to find the root cause then. TransactionIdIsKnownCompleted() is now unused. In 'master', remove it, but I left it in place in backbranches in case it's used by extensions. Also change pg_xact_status() to check TransactionIdIsInProgress(). Previously, it only checked the CLOG, and returned "committed" before the transaction was actually made visible to other queries. Note that this also means that you cannot use pg_xact_status() to reproduce the bug anymore, even if the code wasn't fixed. Report and analysis by Konstantin Knizhnik. Patch by Simon Riggs, with the pg_xact_status() change added by me. Author: Simon Riggs Reviewed-by: Andres Freund Discussion: https://www.postgresql.org/message-id/flat/4da7913d-398c-e2ad-d777-f752cf7f0bbb%40garret.ru
* Revert changes in HOT handling of BRIN indexesTomas Vondra2022-06-16
| | | | | | | | | | | | | | | | | | | | | | | | This reverts commits 5753d4ee32 and fe60b67250 that modified HOT to ignore BRIN indexes. The commit message for 5753d4ee32 claims that: When determining whether an index update may be skipped by using HOT, we can ignore attributes indexed only by BRIN indexes. There are no index pointers to individual tuples in BRIN, and the page range summary will be updated anyway as it relies on visibility info. This is partially incorrect - it's true BRIN indexes don't point to individual tuples, so HOT chains are not an issue, but the visibitlity info is not sufficient to keep the index up to date. This can easily result in corrupted indexes, as demonstrated in the hackers thread. This does not mean relaxing the HOT restrictions for BRIN is a lost cause, but it needs to handle the two aspects (allowing HOT chains and updating the page range summaries) as separate. But that requires a major changes, and it's too late for that in the current dev cycle. Reported-by: Tomas Vondra Discussion: https://postgr.es/m/05ebcb44-f383-86e3-4f31-0a97a55634cf@enterprisedb.com
* Be more careful about GucSource for internally-driven GUC settings.Tom Lane2022-06-08
| | | | | | | | | | | | | | | | | | | | | | | The original advice for hard-wired SetConfigOption calls was to use PGC_S_OVERRIDE, particularly for PGC_INTERNAL GUCs. However, that's really overkill for PGC_INTERNAL GUCs, since there is no possibility that we need to override a user-provided setting. Instead use PGC_S_DYNAMIC_DEFAULT in most places, so that the value will appear with source = 'default' in pg_settings and thereby not be shown by psql's new \dconfig command. The one exception is that when changing in_hot_standby in a hot-standby session, we still use PGC_S_OVERRIDE, because people felt that seeing that in \dconfig would be a good thing. Similarly use PGC_S_DYNAMIC_DEFAULT for the auto-tune value of wal_buffers (if possible, that is if wal_buffers wasn't explicitly set to -1), and for the typical 2MB value of max_stack_depth. In combination these changes remove four not-very-interesting entries from the typical output of \dconfig, all of which people fingered as "why is that showing up?" in the discussion thread. Discussion: https://postgr.es/m/3118455.1649267333@sss.pgh.pa.us
* Silence compiler warnings from some older compilers.Tom Lane2022-06-01
| | | | | | | | | | | | Since a117cebd6, some older gcc versions issue "variable may be used uninitialized in this function" complaints for brin_summarize_range. Silence that using the same coding pattern as in bt_index_check_internal; arguably, a117cebd6 had too narrow a view of which compilers might give trouble. Nathan Bossart and Tom Lane. Back-patch as the previous commit was. Discussion: https://postgr.es/m/20220601163537.GA2331988@nathanxps13
* Fix typo in hash README.Amit Kapila2022-05-31
| | | | | Author: Peter Smith Discussion: https://postgr.es/m/CAHut+Pu-V22PiJF2ym9_NVZe-+qnycfyEX24dZm=7URWhDHJ3w@mail.gmail.com
* Revert "Add single-item cache when looking at topmost XID of a subtrans XID"Michael Paquier2022-05-28
| | | | | | | | | | | | | | | | | | This reverts commit 06f5295 as per issues with this approach, both in terms of efficiency impact and stability. First, contrary to the single-item cache for transaction IDs in transam.c, the cache may finish by not be hit for a long time, and without an invalidation mechanism to clear it, it would cause inconsistent results on wraparound for example. Second, the use of SubTransGetTopmostTransaction() for the caching has a limited impact on performance. SubTransGetParent() could have more impact, though the benchmarking of the single-item approach still needs to be proved, particularly under the conditions where SLRU lookups are stressed in parallel with overflowed snapshots (aka more than 64 subxids generated, for example). After discussion with Andres Freund. Discussion: https://postgr.es/m/20220524235250.gtt3uu5zktfkr4hv@alap3.anarazel.de
* Add 'static' to file-local variables missing it.Andres Freund2022-05-12
| | | | | | | | Noticed when comparing the set of exported symbols without / with -fvisibility=hidden after adding PGDLLIMPORT to intentionally exported symbols. Discussion: https://postgr.es/m/20220512164513.vaheofqp2q24l65r@alap3.anarazel.de
* Pre-beta mechanical code beautification.Tom Lane2022-05-12
| | | | | Run pgindent, pgperltidy, and reformat-dat-files. I manually fixed a couple of comments that pgindent uglified.
* Fix some incorrect preprocessor tests in tuplesort specializationsDavid Rowley2022-05-11
| | | | | | | | | | | | | | | | | | | | | | | | | 697492434 added 3 new quicksort specialization functions for common datatypes. That commit was not very consistent in how it would determine if we're compiling for 32-bit or 64-bit machines. It would sometimes use USE_FLOAT8_BYVAL and at other times check if SIZEOF_DATUM == 8. This could cause theoretical problems due to the way USE_FLOAT8_BYVAL is now defined based on SIZEOF_VOID_P >= 8. If pointers for some reason were ever larger than 8-bytes then we'd end up doing 32-bit comparisons mistakenly. Let's just always check SIZEOF_DATUM >= 8. It also seems that ssup_datum_signed_cmp is just never used on 32-bit builds, so let's just ifdef that out to make sure we never accidentally use that comparison function on such machines. This also allows us to ifdef out 1 of the 3 new specialization quicksort functions in 32-bit builds which seems to shrink down the binary by over 4KB on my machine. In passing, also add the missing DatumGetInt32() / DatumGetInt64() macros in the comparison functions. Discussion: https://postgr.es/m/CAApHDvqcQExRhtRa9hJrJB_5egs3SUfOcutP3m+3HO8A+fZTPA@mail.gmail.com Reviewed-by: John Naylor
* Make relation-enumerating operations be security-restricted operations.Noah Misch2022-05-09
| | | | | | | | | | | | | | | | | | When a feature enumerates relations and runs functions associated with all found relations, the feature's user shall not need to trust every user having permission to create objects. BRIN-specific functionality in autovacuum neglected to account for this, as did pg_amcheck and CLUSTER. An attacker having permission to create non-temp objects in at least one schema could execute arbitrary SQL functions under the identity of the bootstrap superuser. CREATE INDEX (not a relation-enumerating operation) and REINDEX protected themselves too late. This change extends to the non-enumerating amcheck interface. Back-patch to v10 (all supported versions). Sergey Shinderuk, reviewed (in earlier versions) by Alexander Lakhin. Reported by Alexander Lakhin. Security: CVE-2022-1552
* Fix control file update done in restartpoints still running after promotionMichael Paquier2022-05-09
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If a cluster is promoted (aka the control file shows a state different than DB_IN_ARCHIVE_RECOVERY) while CreateRestartPoint() is still processing, this function could miss an update of the control file for "checkPoint" and "checkPointCopy" but still do the recycling and/or removal of the past WAL segments, assuming that the to-be-updated LSN values should be used as reference points for the cleanup. This causes a follow-up restart attempting crash recovery to fail with a PANIC on a missing checkpoint record if the end-of-recovery checkpoint triggered by the promotion did not complete while the cluster abruptly stopped or crashed before the completion of this checkpoint. The PANIC would be caused by the redo LSN referred in the control file as located in a segment already gone, recycled by the previous restartpoint with "checkPoint" out-of-sync in the control file. This commit fixes the update of the control file during restartpoints so as "checkPoint" and "checkPointCopy" are updated even if the cluster has been promoted while a restartpoint is running, to be on par with the set of WAL segments actually recycled in the end of CreateRestartPoint(). This problem exists in all the stable branches. However, commit 7ff23c6, by removing the last call of CreateCheckPoint() from the startup process, has made this bug much easier to reason about as concurrent checkpoints are not possible anymore. No backpatch is done yet, mostly out of caution from me as a point release is close by, but we need to think harder about the case of concurrent checkpoints at promotion if the bgwriter is not considered as running by the startup process in ~v14, so this change is done only on HEAD for the moment. Reported-by: Fujii Masao, Rui Zhao Author: Kyotaro Horiguchi Reviewed-by: Nathan Bossart, Michael Paquier Discussion: https://postgr.es/m/20220316.102444.2193181487576617583.horikyota.ntt@gmail.com