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2 daysExpand usage of macros for protocol characters.Nathan Bossart
This commit makes use of the existing PqMsg_* macros in more places and adds new PqReplMsg_* and PqBackupMsg_* macros for use in special replication and backup messages, respectively. Author: Dave Cramer <davecramer@gmail.com> Co-authored-by: Fabrízio de Royes Mello <fabriziomello@gmail.com> Reviewed-by: Jacob Champion <jacob.champion@enterprisedb.com> Reviewed-by: Álvaro Herrera <alvherre@kurilemu.de> Reviewed-by: Euler Taveira <euler@eulerto.com> Discussion: https://postgr.es/m/aIECfYfevCUpenBT@nathan Discussion: https://postgr.es/m/CAFcNs%2Br73NOUb7%2BqKrV4HHEki02CS96Z%2Bx19WaFgE087BWwEng%40mail.gmail.com
4 daysFix varatt versus Datum type confusionsPeter Eisentraut
Macros like VARDATA() and VARSIZE() should be thought of as taking values of type pointer to struct varlena or some other related struct. The way they are implemented, you can pass anything to it and it will cast it right. But this is in principle incorrect. To fix, add the required DatumGetPointer() calls. Or in a couple of cases, remove superfluous PointerGetDatum() calls. It is planned in a subsequent patch to change macros like VARDATA() and VARSIZE() to inline functions, which will enforce stricter typing. This is in preparation for that. Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us> Discussion: https://www.postgresql.org/message-id/flat/928ea48f-77c6-417b-897c-621ef16685a6%40eisentraut.org
5 daysAvoid unexpected shutdown when sync_replication_slots is enabled.Fujii Masao
Previously, enabling sync_replication_slots while wal_level was not set to logical could cause the server to shut down. This was because the postmaster performed a configuration check before launching the slot synchronization worker and raised an ERROR if the settings were incompatible. Since ERROR is treated as FATAL in the postmaster, this resulted in the entire server shutting down unexpectedly. This commit changes the postmaster to log that message with a LOG-level instead of raising an ERROR, allowing the server to continue running even with the misconfiguration. Back-patch to v17, where slot synchronization was introduced. Reported-by: Hugo DUBOIS <hdubois@scaleway.com> Author: Fujii Masao <masao.fujii@gmail.com> Reviewed-by: Hugo DUBOIS <hdubois@scaleway.com> Reviewed-by: Shveta Malik <shveta.malik@gmail.com> Discussion: https://postgr.es/m/CAH0PTU_pc3oHi__XESF9ZigCyzai1Mo3LsOdFyQA4aUDkm01RA@mail.gmail.com Backpatch-through: 17
5 daysDetect and report update_deleted conflicts.Amit Kapila
This enhancement builds upon the infrastructure introduced in commit 228c370868, which enables the preservation of deleted tuples and their origin information on the subscriber. This capability is crucial for handling concurrent transactions replicated from remote nodes. The update introduces support for detecting update_deleted conflicts during the application of update operations on the subscriber. When an update operation fails to locate the target row-typically because it has been concurrently deleted-we perform an additional table scan. This scan uses the SnapshotAny mechanism and we do this additional scan only when the retain_dead_tuples option is enabled for the relevant subscription. The goal of this scan is to locate the most recently deleted tuple-matching the old column values from the remote update-that has not yet been removed by VACUUM and is still visible according to our slot (i.e., its deletion is not older than conflict-detection-slot's xmin). If such a tuple is found, the system reports an update_deleted conflict, including the origin and transaction details responsible for the deletion. This provides a groundwork for more robust and accurate conflict resolution process, preventing unexpected behavior by correctly identifying cases where a remote update clashes with a deletion from another origin. Author: Zhijie Hou <houzj.fnst@fujitsu.com> Reviewed-by: shveta malik <shveta.malik@gmail.com> Reviewed-by: Nisha Moond <nisha.moond412@gmail.com> Reviewed-by: Dilip Kumar <dilipbalaut@gmail.com> Reviewed-by: Hayato Kuroda <kuroda.hayato@fujitsu.com> Reviewed-by: Amit Kapila <amit.kapila16@gmail.com> Discussion: https://postgr.es/m/OS0PR01MB5716BE80DAEB0EE2A6A5D1F5949D2@OS0PR01MB5716.jpnprd01.prod.outlook.com
6 daysFix assorted pretty-trivial memory leaks in the backend.Tom Lane
In the current system architecture, none of these are worth obsessing over; most are once-per-process leaks. However, Valgrind complains about all of them, and if we get to using threads rather than processes for backend sessions, it will become more interesting to avoid per-session leaks. * Fix leaks in StartupXLOG() and ShutdownWalRecovery(). * Fix leakage of pq_mq_handle in a parallel worker. While at it, move mq_putmessage's "Assert(pq_mq_handle != NULL)" to someplace where it's not trivially useless. * Fix leak in logicalrep_worker_detach(). * Don't leak the startup-packet buffer in ProcessStartupPacket(). * Fix leak in evtcache.c's DecodeTextArrayToBitmapset(). If the presented array is toasted, this neglected to free the detoasted copy, which was then leaked into EventTriggerCacheContext. * I'm distressed by the amount of code that BuildEventTriggerCache is willing to run while switched into a long-lived cache context. Although the detoasted array is the only leak that Valgrind reports, let's tighten things up while we're here. (DecodeTextArrayToBitmapset is still run in the cache context, so doing this doesn't remove the need for the detoast fix. But it reduces the surface area for other leaks.) * load_domaintype_info() intentionally leaked some intermediate cruft into the long-lived DomainConstraintCache's memory context, reasoning that the amount of leakage will typically not be much so it's not worth doing a copyObject() of the final tree to avoid that. But Valgrind knows nothing of engineering tradeoffs and complains anyway. On the whole, the copyObject doesn't cost that much and this is surely not a performance-critical code path, so let's do it the clean way. * MarkGUCPrefixReserved didn't bother to clean up removed placeholder GUCs at all, which shows up as a leak in one regression test. It seems appropriate for it to do as much cleanup as define_custom_variable does when replacing placeholders, so factor that code out into a helper function. define_custom_variable's logic was one brick shy of a load too: it forgot to free the separate allocation for the placeholder's name. Author: Tom Lane <tgl@sss.pgh.pa.us> Reviewed-by: Andres Freund <andres@anarazel.de> Reviewed-by: Richard Guo <guofenglinux@gmail.com> Discussion: https://postgr.es/m/285483.1746756246@sss.pgh.pa.us
7 daysFix use-after-free with INSERT ON CONFLICT changes in reorderbuffer.cMichael Paquier
In ReorderBufferProcessTXN(), used to send the data of a transaction to an output plugin, INSERT ON CONFLICT changes (INTERNAL_SPEC_INSERT) are delayed until a confirmation record arrives (INTERNAL_SPEC_CONFIRM), updating the change being processed. 8c58624df462 has added an extra step after processing a change to update the progress of the transaction, by calling the callback update_progress_txn() based on the LSN stored in a change after a threshold of CHANGES_THRESHOLD (100) is reached. This logic has missed the fact that for an INSERT ON CONFLICT change the data is freed once processed, hence update_progress_txn() could be called pointing to a LSN value that's already been freed. This could result in random crashes, depending on the workload. Per discussion, this issue is fixed by reusing in update_progress_txn() the LSN from the change processed found at the beginning of the loop, meaning that for a INTERNAL_SPEC_CONFIRM change the progress is updated using the LSN of the INTERNAL_SPEC_CONFIRM change, and not the LSN from its INTERNAL_SPEC_INSERT change. This is actually more correct, as we want to update the progress to point to the INTERNAL_SPEC_CONFIRM change. Masahiko Sawada has found a nice trick to reproduce the issue: hardcode CHANGES_THRESHOLD at 1 and run test_decoding (test "ddl" being enough) on an instance running valgrind. The bug has been analyzed by Ethan Mertz, who also originally suggested the solution used in this patch. Issue introduced by 8c58624df462, so backpatch down to v16. Author: Ethan Mertz <ethan.mertz@gmail.com> Co-authored-by: Michael Paquier <michael@paquier.xyz> Reviewed-by: Amit Kapila <amit.kapila16@gmail.com> Reviewed-by: Masahiko Sawada <sawada.mshk@gmail.com> Discussion: https://postgr.es/m/aIsQqDZ7x4LAQ6u1@paquier.xyz Backpatch-through: 16
8 daysFix a deadlock during ALTER SUBSCRIPTION ... DROP PUBLICATION.Amit Kapila
A deadlock can occur when the DDL command and the apply worker acquire catalog locks in different orders while dropping replication origins. The issue is rare in PG16 and higher branches because, in most cases, the tablesync worker performs the origin drop in those branches, and its locking sequence does not conflict with DDL operations. This patch ensures consistent lock acquisition to prevent such deadlocks. As per buildfarm. Reported-by: Alexander Lakhin <exclusion@gmail.com> Author: Ajin Cherian <itsajin@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> Backpatch-through: 14, where it was introduced Discussion: https://postgr.es/m/bab95e12-6cc5-4ebb-80a8-3e41956aa297@gmail.com
11 daysAvoid throwing away the error message in syncrep_yyerror.Robert Haas
Commit 473a575e05979b4dbb28b3f2544f4ec8f184ce65 purported to make this function stash the error message in *syncrep_parse_result_p, but it didn't actually. As a result, an attempt to set synchronous_standby_names to any value that does not parse resulted in a generic "parser failed." message rather than anything more specific. This fixes that. Discussion: http://postgr.es/m/CA+TgmoYF9wPNZ-Q_EMfib_espgHycY-eX__6Tzo2GpYpVXqCdQ@mail.gmail.com Backpatch-through: 18
2025-07-25Reap the benefits of not having to avoid leaking PGresults.Tom Lane
Remove a bunch of PG_TRY constructs, de-volatilize related variables, remove some PQclear calls in error paths. Aside from making the code simpler and shorter, this should provide some marginal performance gains. For ease of review, I did not re-indent code within the removed PG_TRY constructs. That'll be done in a separate patch. Author: Tom Lane <tgl@sss.pgh.pa.us> Reviewed-by: Matheus Alcantara <matheusssilv97@gmail.com> Discussion: https://postgr.es/m/2976982.1748049023@sss.pgh.pa.us
2025-07-23Use PqMsg_* macros in walsender.cNathan Bossart
Oversights in commits f4b54e1ed9, dc21234005, and 228c370868. Author: Dave Cramer <davecramer@gmail.com> Discussion: https://postgr.es/m/CADK3HH%2BowWVdnbmWH4NHG8%3D%2BkXA_wjsyEVLoY719iJnb%3D%2BtT6A%40mail.gmail.com
2025-07-23Preserve conflict-relevant data during logical replication.Amit Kapila
Logical replication requires reliable conflict detection to maintain data consistency across nodes. To achieve this, we must prevent premature removal of tuples deleted by other origins and their associated commit_ts data by VACUUM, which could otherwise lead to incorrect conflict reporting and resolution. This patch introduces a mechanism to retain deleted tuples on the subscriber during the application of concurrent transactions from remote nodes. Retaining these tuples allows us to correctly ignore concurrent updates to the same tuple. Without this, an UPDATE might be misinterpreted as an INSERT during resolutions due to the absence of the original tuple. Additionally, we ensure that origin metadata is not prematurely removed by vacuum freeze, which is essential for detecting update_origin_differs and delete_origin_differs conflicts. To support this, a new replication slot named pg_conflict_detection is created and maintained by the launcher on the subscriber. Each apply worker tracks its own non-removable transaction ID, which the launcher aggregates to determine the appropriate xmin for the slot, thereby retaining necessary tuples. Conflict information retention (deleted tuples and commit_ts) can be enabled per subscription via the retain_conflict_info option. This is disabled by default to avoid unnecessary overhead for configurations that do not require conflict resolution or logging. During upgrades, if any subscription on the old cluster has retain_conflict_info enabled, a conflict detection slot will be created to protect relevant tuples from deletion when the new cluster starts. This is a foundational work to correctly detect update_deleted conflict which will be done in a follow-up patch. Author: Zhijie Hou <houzj.fnst@fujitsu.com> Reviewed-by: shveta malik <shveta.malik@gmail.com> Reviewed-by: Masahiko Sawada <sawada.mshk@gmail.com> Reviewed-by: Dilip Kumar <dilipbalaut@gmail.com> Reviewed-by: Nisha Moond <nisha.moond412@gmail.com> Reviewed-by: Amit Kapila <amit.kapila16@gmail.com> Discussion: https://postgr.es/m/OS0PR01MB5716BE80DAEB0EE2A6A5D1F5949D2@OS0PR01MB5716.jpnprd01.prod.outlook.com
2025-07-22Remove translation marker from libpq-be-fe-helpers.h.Fujii Masao
Commit 112faf1378e introduced a translation marker in libpq-be-fe-helpers.h, but this caused build failures on some platforms—such as the one reported by buildfarm member indri—due to linker issues with dblink. This is the same problem previously addressed in commit 213c959a294. To fix the issue, this commit removes the translation marker from libpq-be-fe-helpers.h, following the approach used in 213c959a294. It also removes the associated gettext_noop() calls added in commit 112faf1378e, as they are no longer needed. While reviewing this, a gettext_noop() call was also found in contrib/basic_archive. Since contrib modules don't support translation, this call has been removed as well. Per buildfarm member indri. Author: Fujii Masao <masao.fujii@gmail.com> Reviewed-by: Álvaro Herrera <alvherre@kurilemu.de> Discussion: https://postgr.es/m/0e6299d9-608a-4ffa-aeb1-40cb8a99000b@oss.nttdata.com
2025-07-22Log remote NOTICE, WARNING, and similar messages using ereport().Fujii Masao
Previously, NOTICE, WARNING, and similar messages received from remote servers over replication, postgres_fdw, or dblink connections were printed directly to stderr on the local server (e.g., the subscriber). As a result, these messages lacked log prefixes (e.g., timestamp), making them harder to trace and correlate with other log entries. This commit addresses the issue by introducing a custom notice receiver for replication, postgres_fdw, and dblink connections. These messages are now logged via ereport(), ensuring they appear in the logs with proper formatting and context, which improves clarity and aids in debugging. Author: Vignesh C <vignesh21@gmail.com> Reviewed-by: Álvaro Herrera <alvherre@kurilemu.de> Reviewed-by: Fujii Masao <masao.fujii@gmail.com> Discussion: https://postgr.es/m/CALDaNm2xsHpWRtLm-VL_HJCsaE3+1Y_n-jDEAr3-suxVqc3xoQ@mail.gmail.com
2025-07-16pgoutput: Initialize missing default for "origin" parameter.Fujii Masao
The pgoutput plugin initializes optional parameters like "binary" with default values at the start of processing. However, the "origin" parameter was previously missed and left without explicit initialization. Although the PGOutputData struct, which holds these settings, is zero-initialized at allocation (resulting in publish_no_origin field for "origin" parameter being false by default), this default was not set explicitly, unlike other parameters. This commit adds explicit initialization of the "origin" parameter to ensure consistency and clarity in how defaults are handled. Author: Fujii Masao <masao.fujii@gmail.com> Reviewed-by: Euler Taveira <euler@eulerto.com> Discussion: https://postgr.es/m/d2790f10-238d-4cb5-a743-d9d2a9dd900f@oss.nttdata.com
2025-07-11Fix the handling of two GUCs during upgrade.Amit Kapila
Previously, the check_hook functions for max_slot_wal_keep_size and idle_replication_slot_timeout would incorrectly raise an ERROR for values set in postgresql.conf during upgrade, even though those values were not actively used in the upgrade process. To prevent logical slot invalidation during upgrade, we used to set special values for these GUCs. Now, instead of relying on those values, we directly prevent WAL removal and logical slot invalidation caused by max_slot_wal_keep_size and idle_replication_slot_timeout. Note: PostgreSQL 17 does not include the idle_replication_slot_timeout GUC, so related changes were not backported. BUG #18979 Reported-by: jorsol <jorsol@gmail.com> Author: Dilip Kumar <dilipbalaut@gmail.com> Reviewed by: vignesh C <vignesh21@gmail.com> Reviewed by: Alvaro Herrera <alvherre@alvh.no-ip.org> Backpatch-through: 17, where it was introduced Discussion: https://postgr.es/m/219561.1751826409@sss.pgh.pa.us Discussion: https://postgr.es/m/18979-a1b7fdbb7cd181c6@postgresql.org
2025-07-11doc: Clarify meaning of "idle" in idle_replication_slot_timeout.Fujii Masao
This commit updates the documentation to clarify that "idle" in idle_replication_slot_timeout means the replication slot is inactive, that is, not currently used by any replication connection. Without this clarification, "idle" could be misinterpreted to mean that the slot is not advancing or that no data is being streamed, even if a connection exists. Back-patch to v18 where idle_replication_slot_timeout was added. Author: Laurenz Albe <laurenz.albe@cybertec.at> Reviewed-by: David G. Johnston <david.g.johnston@gmail.com> Reviewed-by: Gunnar Morling <gunnar.morling@googlemail.com> Reviewed-by: Amit Kapila <amit.kapila16@gmail.com> Reviewed-by: Fujii Masao <masao.fujii@gmail.com> Discussion: https://postgr.es/m/CADGJaX_0+FTguWpNSpgVWYQP_7MhoO0D8=cp4XozSQgaZ40Odw@mail.gmail.com Backpatch-through: 18
2025-07-11Change unit of idle_replication_slot_timeout to seconds.Fujii Masao
Previously, the idle_replication_slot_timeout parameter used minutes as its unit, based on the assumption that values would typically exceed one minute in production environments. However, this caused unexpected behavior: specifying a value below 30 seconds would round down to 0, effectively disabling the timeout. This could be surprising to users. To allow finer-grained control and avoid such confusion, this commit changes the unit of idle_replication_slot_timeout to seconds. Larger values can still be specified easily using standard time suffixes, for example, '24h' for 24 hours. Back-patch to v18 where idle_replication_slot_timeout was added. Reported-by: Gunnar Morling <gunnar.morling@googlemail.com> Author: Fujii Masao <masao.fujii@gmail.com> Reviewed-by: Laurenz Albe <laurenz.albe@cybertec.at> Reviewed-by: David G. Johnston <david.g.johnston@gmail.com> Reviewed-by: Amit Kapila <amit.kapila16@gmail.com> Reviewed-by: Hayato Kuroda <kuroda.hayato@fujitsu.com> Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us> Discussion: https://postgr.es/m/CADGJaX_0+FTguWpNSpgVWYQP_7MhoO0D8=cp4XozSQgaZ40Odw@mail.gmail.com Backpatch-through: 18
2025-07-07Standardize LSN formatting by zero paddingÁlvaro Herrera
This commit standardizes the output format for LSNs to ensure consistent representation across various tools and messages. Previously, LSNs were inconsistently printed as `%X/%X` in some contexts, while others used zero-padding. This often led to confusion when comparing. To address this, the LSN format is now uniformly set to `%X/%08X`, ensuring the lower 32-bit part is always zero-padded to eight hexadecimal digits. Author: Japin Li <japinli@hotmail.com> Reviewed-by: Masahiko Sawada <sawada.mshk@gmail.com> Reviewed-by: Álvaro Herrera <alvherre@kurilemu.de> Discussion: https://postgr.es/m/ME0P300MB0445CA53CA0E4B8C1879AF84B641A@ME0P300MB0445.AUSP300.PROD.OUTLOOK.COM
2025-07-01Make more use of binaryheap_empty() and binaryheap_size().Nathan Bossart
A few places were accessing bh_size directly instead of via these handy macros. Author: Aleksander Alekseev <aleksander@timescale.com> Discussion: https://postgr.es/m/CAJ7c6TPQMVL%2B028T4zuw9ZqL5Du9JavOLhBQLkJeK0RznYx_6w%40mail.gmail.com
2025-06-28Message style improvementsPeter Eisentraut
2025-06-27Fix CheckPointReplicationSlots() with max_replication_slots == 0Alexander Korotkov
ca307d5cec90 made CheckPointReplicationSlots() unconditionally call ReplicationSlotsComputeRequiredLSN(). It causes an assertion trap when max_replication_slots equals 0. This commit makes CheckPointReplicationSlots() call ReplicationSlotsComputeRequiredLSN() only when at least one slot gets its last_saved_restart_lsn updated. That avoids an assert trap and also saves some cycles when no one slot has last_saved_restart_lsn updated. Based on ideas from Dilip Kumar <dilipbalaut@gmail.com> and Hayato Kuroda <kuroda.hayato@fujitsu.com>. Reported-by: Zhijie Hou <houzj.fnst@fujitsu.com> Discussion: https://postgr.es/m/OS0PR01MB5716BB506AF934376FF3A8BB947BA%40OS0PR01MB5716.jpnprd01.prod.outlook.com
2025-06-24Prevent excessive delays before launching new logrep workers.Tom Lane
The logical replication launcher process would sometimes sleep for as much as 3 minutes before noticing that it is supposed to launch a new worker. This could happen if (1) WaitForReplicationWorkerAttach absorbed a process latch wakeup that was meant to cause ApplyLauncherMain to do work, or (2) logicalrep_worker_launch reported failure, either because of resource limits or because the new worker terminated immediately. In case (2), the expected behavior is that we retry the launch after wal_retrieve_retry_interval, but that didn't reliably happen. It's not clear how often such conditions would occur in the field, but in our subscription test suite they are somewhat common, especially in tests that exercise cases that cause quick worker failure. That causes the tests to take substantially longer than they ought to do on typical setups. To fix (1), make WaitForReplicationWorkerAttach re-set the latch before returning if it cleared it while looping. To fix (2), ensure that we reduce wait_time to no more than wal_retrieve_retry_interval when logicalrep_worker_launch reports failure. In passing, fix a couple of perhaps-hypothetical race conditions, e.g. examining worker->in_use without a lock. Backpatch to v16. Problem (2) didn't exist before commit 5a3a95385 because the previous code always set wait_time to wal_retrieve_retry_interval when launching a worker, regardless of success or failure of the launch. That behavior also greatly mitigated problem (1), so I'm not excited about adapting the remainder of the patch to the substantially-different code in older branches. Author: Tom Lane <tgl@sss.pgh.pa.us> Reviewed-by: Amit Kapila <amit.kapila16@gmail.com> Reviewed-by: Ashutosh Bapat <ashutosh.bapat.oss@gmail.com> Discussion: https://postgr.es/m/817604.1750723007@sss.pgh.pa.us Backpatch-through: 16
2025-06-24Fix missing comment update in 1462aad2e4.Amit Kapila
Remove the part of comment that says we don't allow toggling two_phase option as that is supported in commit 1462aad2e4. Author: Hayato Kuroda <kuroda.hayato@fujitsu.com> Author: Amit Kapila <amit.kapila16@gmail.com> Discussion: https://postgr.es/m/OSCPR01MB1496656725F3951AEE8749EBDF579A@OSCPR01MB14966.jpnprd01.prod.outlook.com
2025-06-23Remove excess assert from InvalidatePossiblyObsoleteSlot()Alexander Korotkov
ca307d5cec90 introduced keeping WAL segments by slot's last saved restart LSN. It also added an assertion that the slot's restart LSN never goes backward. However, situations when the restart LSN goes backward have been spotted by buildfarm animals and investigated in the thread. When pg_receivewal starts the replication, it sets the last replayed LSN to the beginning of the segment, which is older than what ReplicationSlotReserveWal() set for the slot. A similar situation can happen to pg_basebackup. When standby reconnects to the primary, it sends the last replayed LSN, which might be older than the last confirmed flush LSN. In both these situations, a concurrent checkpoint may trigger an assert trap. Based on ideas from Vitaly Davydov <v.davydov@postgrespro.ru>, Hayato Kuroda (Fujitsu) <kuroda.hayato@fujitsu.com>, Vignesh C <vignesh21@gmail.com>, Amit Kapila <amit.kapila16@gmail.com>. Reported-by: Vignesh C <vignesh21@gmail.com> Reported-by: Tom Lane <tgl@sss.pgh.pa.us> Discussion: https://postgr.es/m/CALDaNm3s-jpQTe1MshsvQ8GO%3DTLj233JCdkQ7uZ6pwqRVpxAdw%40mail.gmail.com Reviewed-by: Vignesh C <vignesh21@gmail.com> Reviewed-by: Amit Kapila <amit.kapila16@gmail.com>
2025-06-19Improve log messages and docs for slot synchronization.Amit Kapila
Improve the clarity of LOG messages when a failover logical slot synchronization fails, making the reasons more explicit for easier debugging. Update the documentation to outline scenarios where slot synchronization can fail, especially during the initial sync, and emphasize that pg_sync_replication_slot() is primarily intended for testing and debugging purposes. We also discussed improving the functionality of pg_sync_replication_slot() so that it can be used reliably, but we would take up that work for next version after some more discussion and review. Reported-by: Suraj Kharage <suraj.kharage@enterprisedb.com> Author: shveta malik <shveta.malik@gmail.com> Reviewed-by: Zhijie Hou <houzj.fnst@fujitsu.com> Reviewed-by: Peter Smith <smithpb2250@gmail.com> Reviewed-by: Amit Kapila <amit.kapila16@gmail.com> Backpatch-through: 17, where it was introduced Discussion: https://postgr.es/m/CAF1DzPWTcg+m+x+oVVB=y4q9=PYYsL_mujVp7uJr-_oUtWNGbA@mail.gmail.com
2025-06-16Fix re-distributing previously distributed invalidation messages during ↵Masahiko Sawada
logical decoding. Commit 4909b38af0 introduced logic to distribute invalidation messages from catalog-modifying transactions to all concurrent in-progress transactions. However, since each transaction distributes not only its original invalidation messages but also previously distributed messages to other transactions, this leads to an exponential increase in allocation request size for invalidation messages, ultimately causing memory allocation failure. This commit fixes this issue by tracking distributed invalidation messages separately per decoded transaction and not redistributing these messages to other in-progress transactions. The maximum size of distributed invalidation messages that one transaction can store is limited to MAX_DISTR_INVAL_MSG_PER_TXN (8MB). Once the size of the distributed invalidation messages exceeds this threshold, we invalidate all caches in locations where distributed invalidation messages need to be executed. Back-patch to all supported versions where we introduced the fix by commit 4909b38af0. Note that this commit adds two new fields to ReorderBufferTXN to store the distributed transactions. This change breaks ABI compatibility in back branches, affecting third-party extensions that depend on the size of the ReorderBufferTXN struct, though this scenario seems unlikely. Additionally, it adds a new flag to the txn_flags field of ReorderBufferTXN to indicate distributed invalidation message overflow. This should not affect existing implementations, as it is unlikely that third-party extensions use unused bits in the txn_flags field. Bug: #18938 #18942 Author: vignesh C <vignesh21@gmail.com> Reported-by: Duncan Sands <duncan.sands@deepbluecap.com> Reported-by: John Hutchins <john.hutchins@wicourts.gov> Reported-by: Laurence Parry <greenreaper@hotmail.com> Reported-by: Max Madden <maxmmadden@gmail.com> Reported-by: Braulio Fdo Gonzalez <brauliofg@gmail.com> Reviewed-by: Masahiko Sawada <sawada.mshk@gmail.com> Reviewed-by: Amit Kapila <amit.kapila16@gmail.com> Reviewed-by: Hayato Kuroda <kuroda.hayato@fujitsu.com> Discussion: https://postgr.es/m/680bdaf6-f7d1-4536-b580-05c2760c67c6@deepbluecap.com Discussion: https://postgr.es/m/18942-0ab1e5ae156613ad@postgresql.org Discussion: https://postgr.es/m/18938-57c9a1c463b68ce0@postgresql.org Discussion: https://postgr.es/m/CAD1FGCT2sYrP_70RTuo56QTizyc+J3wJdtn2gtO3VttQFpdMZg@mail.gmail.com Discussion: https://postgr.es/m/CANO2=B=2BT1hSYCE=nuuTnVTnjidMg0+-FfnRnqM6kd23qoygg@mail.gmail.com Backpatch-through: 13
2025-06-14Add TAP tests to check replication slot advance during the checkpointAlexander Korotkov
The new tests verify that logical and physical replication slots are still valid after an immediate restart on checkpoint completion when the slot was advanced during the checkpoint. This commit introduces two new injection points to make these tests possible: * checkpoint-before-old-wal-removal - triggered in the checkpointer process just before old WAL segments cleanup; * logical-replication-slot-advance-segment - triggered in LogicalConfirmReceivedLocation() when restart_lsn was changed enough to point to the next WAL segment. Discussion: https://postgr.es/m/flat/1d12d2-67235980-35-19a406a0%4063439497 Author: Vitaly Davydov <v.davydov@postgrespro.ru> Author: Tomas Vondra <tomas@vondra.me> Reviewed-by: Alexander Korotkov <aekorotkov@gmail.com> Reviewed-by: Amit Kapila <amit.kapila16@gmail.com> Backpatch-through: 17
2025-06-14Keep WAL segments by slot's last saved restart LSNAlexander Korotkov
The patch fixes the issue with the unexpected removal of old WAL segments after checkpoint, followed by an immediate restart. The issue occurs when a slot is advanced after the start of the checkpoint and before old WAL segments are removed at the end of the checkpoint. The patch introduces a new in-memory state for slots: last_saved_restart_lsn, which is used to calculate the oldest LSN for removing WAL segments. This state is updated every time with the current restart_lsn at the moment when the slot is saved to disk. This fix changes the shared memory layout. It's applied to HEAD only because we don't have to preserve ABI compatibility during the beta stage. Another fix that doesn't affect the ABI is committed to back branches. Discussion: https://postgr.es/m/1d12d2-67235980-35-19a406a0%4063439497 Author: Vitaly Davydov <v.davydov@postgrespro.ru> Author: Alexander Korotkov <aekorotkov@gmail.com> Reviewed-by: Amit Kapila <amit.kapila16@gmail.com>
2025-06-06Use NULL instead of 0 for pointer arguments.Nathan Bossart
Commit 5fe08c006c fixed this for calls to dshash_create(). This commit fixes calls to dshash_attach() and dsa_create_in_place(). Reviewed-by: Masahiko Sawada <sawada.mshk@gmail.com> Reviewed-by: Michael Paquier <michael@paquier.xyz> Discussion: https://postgr.es/m/aECi_gSD9JnVWQ8T%40nathan
2025-06-02Use replay LSN as target for cascading logical WAL sendersMichael Paquier
A cascading WAL sender doing logical decoding (as known as doing its work on a standby) has been using as flush LSN the value returned by GetStandbyFlushRecPtr() (last position safely flushed to disk). This is incorrect as such processes are only able to decode changes up to the LSN that has been replayed by the startup process. This commit changes cascading logical WAL senders to use the replay LSN, as returned by GetXLogReplayRecPtr(). This distinction is important particularly during shutdown, when WAL senders need to send any remaining available data to their clients, switching WAL senders to a caught-up state. Using the latest flush LSN rather than the replay LSN could cause the WAL senders to be stuck in an infinite loop preventing them to shut down, as the startup process does not run when WAL senders attempt to catch up, so they could keep waiting for work that would never happen. Backpatch down to v16, where logical decoding on standbys has been introduced. Author: Alexey Makhmutov <a.makhmutov@postgrespro.ru> Reviewed-by: Ajin Cherian <itsajin@gmail.com> Reviewed-by: Bertrand Drouvot <bertranddrouvot.pg@gmail.com> Reviewed-by: Michael Paquier <michael@paquier.xyz> Discussion: https://postgr.es/m/52138028-7246-421c-9161-4fa108b88070@postgrespro.ru Backpatch-through: 16
2025-05-30Ensure we have a snapshot when updating various system catalogs.Nathan Bossart
A few places that access system catalogs don't set up an active snapshot before potentially accessing their TOAST tables. To fix, push an active snapshot just before each section of code that might require accessing one of these TOAST tables, and pop it shortly afterwards. While at it, this commit adds some rather strict assertions in an attempt to prevent such issues in the future. Commit 16bf24e0e4 recently removed pg_replication_origin's TOAST table in order to fix the same problem for that catalog. On the back-branches, those bugs are left in place. We cannot easily remove a catalog's TOAST table on released major versions, and only replication origins with extremely long names are affected. Given the low severity of the issue, fixing older versions doesn't seem worth the trouble of significantly modifying the patch. Also, on v13 and v14, the aforementioned strict assertions have been omitted because commit 2776922201, which added HaveRegisteredOrActiveSnapshot(), was not back-patched. While we could probably back-patch it now, I've opted against it because it seems unlikely that new TOAST snapshot issues will be introduced in the oldest supported versions. Reported-by: Alexander Lakhin <exclusion@gmail.com> Reviewed-by: Michael Paquier <michael@paquier.xyz> Discussion: https://postgr.es/m/18127-fe54b6a667f29658%40postgresql.org Discussion: https://postgr.es/m/18309-c0bf914950c46692%40postgresql.org Discussion: https://postgr.es/m/ZvMSUPOqUU-VNADN%40nathan Backpatch-through: 13
2025-05-19Don't retreat slot's confirmed_flush LSN.Amit Kapila
Prevent moving the confirmed_flush backwards, as this could lead to data duplication issues caused by replicating already replicated changes. This can happen when a client acknowledges an LSN it doesn't have to do anything for, and thus didn't store persistently. After a restart, the client can send the prior LSN that it stored persistently as an acknowledgement, but we need to ignore such an LSN to avoid retreating confirm_flush LSN. Diagnosed-by: Zhijie Hou <houzj.fnst@fujitsu.com> Author: shveta malik <shveta.malik@gmail.com> Reviewed-by: Amit Kapila <amit.kapila16@gmail.com> Reviewed-by: Dilip Kumar <dilipbalaut@gmail.com> Tested-by: Nisha Moond <nisha.moond412@gmail.com> Backpatch-through: 13 Discussion: https://postgr.es/m/CAJpy0uDZ29P=BYB1JDWMCh-6wXaNqMwG1u1mB4=10Ly0x7HhwQ@mail.gmail.com Discussion: https://postgr.es/m/OS0PR01MB57164AB5716AF2E477D53F6F9489A@OS0PR01MB5716.jpnprd01.prod.outlook.com
2025-05-07Remove pg_replication_origin's TOAST table.Nathan Bossart
A few places that access this catalog don't set up an active snapshot before potentially accessing its TOAST table. However, roname (the replication origin name) is the only varlena column, so this is only a problem if the name requires out-of-line storage. This commit removes its TOAST table to avoid needing to set up a snapshot. It also places a limit on replication origin names so that attempts to set long names will fail with a more user-friendly error. Those chosen limit of 512 bytes should be sufficient to avoid "row is too big" errors independent of BLCKSZ, but it should also be lenient enough for all reasonable use-cases. Bumps catversion. Reviewed-by: Michael Paquier <michael@paquier.xyz> Reviewed-by: Amit Kapila <amit.kapila16@gmail.com> Reviewed-by: Euler Taveira <euler@eulerto.com> Reviewed-by: Nisha Moond <nisha.moond412@gmail.com> Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us> Discussion: https://postgr.es/m/ZvMSUPOqUU-VNADN%40nathan
2025-04-29Fix assertion failure during decoding from synced slots.Amit Kapila
The slot synchronization skips updating the confirmed_flush LSN of the local slot if the local slot has a newer catalog_xmin or restart_lsn, but still allows updating the two_phase and two_phase_at fields of the slot. This opens up a window for the prepared transactions between old confirmed_flush LSN and two_phase_at to unexpectedly get decoded and sent to the downstream after promotion. Then, while decoding the commit prepared the assert will fail, which expects that the prepare hasn't been sent to the downstream. The fix is to skip updating the other slot fields when we are skipping to update the confirmed_flush LSN of the slot. We didn't backpatch this commit as two_phase_at was not synced in back branches, which means prepared transactions won't be unexpectedly sent to downstream. We discovered this problem while analyzing BF failure reported in the discussion link. Reliably reproducing this issue without a debugger is difficult. Given its rarity, adding specific injection point to test it doesn't seem worthwhile, so we won't be adding a dedicated test case. Author: Zhijie Hou <houzj.fnst@fujitsu.com> Reviewed-by: shveta malik <shveta.malik@gmail.com> Reviewed-by: Masahiko Sawada <sawada.mshk@gmail.com> Reviewed-by: Amit Kapila <amit.kapila16@gmail.com> Discussion: https://postgr.es/m/OS0PR01MB5716B44052000EB91EFAE60E94BC2@OS0PR01MB5716.jpnprd01.prod.outlook.com
2025-04-28Fix xmin advancement during fast_forward decoding.Amit Kapila
During logical decoding, we advance catalog_xmin of logical too early in fast_forward mode, resulting in required catalog data being removed by vacuum. This mode is normally used to advance the slot without processing the changes, but we still can't let the slot's xmin to advance to an incorrect value. Commit f49a80c481 fixed a similar issue where the logical slot's catalog_xmin was getting advanced prematurely during non-fast-forward mode. During xl_running_xacts processing, instead of directly advancing the slot's xmin to the oldest running xid in the record, it allowed the xmin to be held back for snapshots that can be used for not-yet-replayed transactions, as those might consider older txns as running too. However, it missed the fact that the same problem can happen during fast_forward mode decoding, as we won't build a base snapshot in that mode, and the future call to get_changes from the same slot can miss seeing the required catalog changes leading to incorrect reslts. This commit allows building the base snapshot even in fast_forward mode to prevent the early advancement of xmin. Reported-by: Amit Kapila <amit.kapila16@gmail.com> Author: Zhijie Hou <houzj.fnst@fujitsu.com> Reviewed-by: Masahiko Sawada <sawada.mshk@gmail.com> Reviewed-by: shveta malik <shveta.malik@gmail.com> Reviewed-by: Amit Kapila <amit.kapila16@gmail.com> Backpatch-through: 13 Discussion: https://postgr.es/m/CAA4eK1LqWncUOqKijiafe+Ypt1gQAQRjctKLMY953J79xDBgAg@mail.gmail.com Discussion: https://postgr.es/m/OS0PR01MB57163087F86621D44D9A72BF94BB2@OS0PR01MB5716.jpnprd01.prod.outlook.com
2025-04-23Fix an oversight in 3f28b2fcac.Amit Kapila
Commit 3f28b2fcac tried to ensure that the replication origin shouldn't be advanced in case of an ERROR in the apply worker, so that it can request the same data again after restart. However, it is possible that an ERROR was caught and handled by a (say PL/pgSQL) function, and the apply worker continues to apply further changes, in which case, we shouldn't reset the replication origin. Ensure to reset the origin only when the apply worker exits after an ERROR. Commit 3f28b2fcac added new function geterrlevel, which we removed in HEAD as part of this commit, but kept it in backbranches to avoid breaking any applications. A separate case can be made to have such a function even for HEAD. Reported-by: Shawn McCoy <shawn.the.mccoy@gmail.com> Author: Hayato Kuroda <kuroda.hayato@fujitsu.com> Reviewed-by: Masahiko Sawada <sawada.mshk@gmail.com> Reviewed-by: vignesh C <vignesh21@gmail.com> Reviewed-by: Amit Kapila <amit.kapila16@gmail.com> Backpatch-through: 16, where it was introduced Discussion: https://postgr.es/m/CALsgZNCGARa2mcYNVTSj9uoPcJo-tPuWUGECReKpNgTpo31_Pw@mail.gmail.com
2025-04-21Use the same cmd_context throughout a walsender's lifetime.Tom Lane
exec_replication_command created a cmd_context to work in and then deleted it on exit. This is pretty dangerous because some replication commands start/finish transactions. In the wake of commit 1afe31f03, that could lead to re-selecting a CurrentMemoryContext that's already been deleted, leading to hilarity such as a memory context that is its own parent. To fix, let's make the cmd_context persist across exec_replication_command calls; instead of deleting it, we'll just reset it each time. In this way it retains the same identity and there's no problem if transaction abort restores it as the working context. It probably even saves a few microseconds to do this. This fix also ensures that exec_replication_command returns to the caller (PostgresMain) with the same context active that had been when it was called (probably MessageContext). The previous coding could get that wrong too. Reported-by: Anthonin Bonnefoy <anthonin.bonnefoy@datadoghq.com> Author: Anthonin Bonnefoy <anthonin.bonnefoy@datadoghq.com> Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us> Discussion: https://postgr.es/m/CAO6_XqoJA7-_G6t7Uqe5nWF3nj+QBGn4F6Ptp=rUGDr0zo+KvA@mail.gmail.com
2025-04-11Fix race with synchronous_standby_names at startupMichael Paquier
synchronous_standby_names cannot be reloaded safely by backends, and the checkpointer is in charge of updating a state in shared memory if the GUC is enabled in WalSndCtl, to let the backends know if they should wait or not for a given LSN. This provides a strict control on the timing of the waiting queues if the GUC is enabled or disabled, then reloaded. The checkpointer is also in charge of waking up the backends that could be waiting for a LSN when the GUC is disabled. This logic had a race condition at startup, where it would be possible for backends to not wait for a LSN even if synchronous_standby_names is enabled. This would cause visibility issues with transactions that we should be waiting for but they were not. The problem lasts until the checkpointer does its initial update of the shared memory state when it loads synchronous_standby_names. In order to take care of this problem, the shared memory state in WalSndCtl is extended to detect if it has been initialized by the checkpointer, and not only check if synchronous_standby_names is defined. In WalSndCtlData, sync_standbys_defined is renamed to sync_standbys_status, a bits8 able to know about two states: - If the shared memory state has been initialized. This flag is set by the checkpointer at startup once, and never removed. - If synchronous_standby_names is known as defined in the shared memory state. This is the same as the previous sync_standbys_defined in WalSndCtl. This method gives a way for backends to decide what they should do until the shared memory area is initialized, and they now ultimately fall back to a check on the GUC value in this case, which is the best thing that can be done. Fortunately, SyncRepUpdateSyncStandbysDefined() is called immediately by the checkpointer when this process starts, so the window is very narrow. It is possible to enlarge the problematic window by making the checkpointer wait at the beginning of SyncRepUpdateSyncStandbysDefined() with a hardcoded sleep for example, and doing so has showed that a 2PC visibility test is indeed failing. On machines slow enough, this bug would cause spurious failures. In 17~, we have looked at the possibility of adding an injection point to have a reproducible test, but as the problematic window happens at early startup, we would need to invent a way to make an injection point optionally persistent across restarts when attached, something that would be fine for this case as it would involve the checkpointer. This issue is quite old, and can be reproduced on all the stable branches. Author: Melnikov Maksim <m.melnikov@postgrespro.ru> Co-authored-by: Michael Paquier <michael@paquier.xyz> Discussion: https://postgr.es/m/163fcbec-900b-4b07-beaa-d2ead8634bec@postgrespro.ru Backpatch-through: 13
2025-04-11Improve various new-to-v18 appendStringInfo callsDavid Rowley
Similar to 8461424fd, here we adjust a few new locations which were not using the most suitable appendStringInfo* function for the intended purpose. Author: David Rowley <drowleyml@gmail.com Discussion: https://postgr.es/m/CAApHDvqJnNjueb=Eoj8K+8n0g7nj_AcPWSiCj5RNV4fDejAfqA@mail.gmail.com
2025-04-10Fix data loss in logical replication.Amit Kapila
Data loss can happen when the DDLs like ALTER PUBLICATION ... ADD TABLE ... or ALTER TYPE ... that don't take a strong lock on table happens concurrently to DMLs on the tables involved in the DDL. This happens because logical decoding doesn't distribute invalidations to concurrent transactions and those transactions use stale cache data to decode the changes. The problem becomes bigger because we keep using the stale cache even after those in-progress transactions are finished and skip the changes required to be sent to the client. This commit fixes the issue by distributing invalidation messages from catalog-modifying transactions to all concurrent in-progress transactions. This allows the necessary rebuild of the catalog cache when decoding new changes after concurrent DDL. We observed performance regression primarily during frequent execution of *publication DDL* statements that modify the published tables. The regression is minor or nearly nonexistent for DDLs that do not affect the published tables or occur infrequently, making this a worthwhile cost to resolve a longstanding data loss issue. An alternative approach considered was to take a strong lock on each affected table during publication modification. However, this would only address issues related to publication DDLs (but not the ALTER TYPE ...) and require locking every relation in the database for publications created as FOR ALL TABLES, which is impractical. The bug exists in all supported branches, but we are backpatching till 14. The fix for 13 requires somewhat bigger changes than this fix, so the fix for that branch is still under discussion. Reported-by: hubert depesz lubaczewski <depesz@depesz.com> Reported-by: Tomas Vondra <tomas.vondra@enterprisedb.com> Author: Shlok Kyal <shlok.kyal.oss@gmail.com> Author: Hayato Kuroda <kuroda.hayato@fujitsu.com> Reviewed-by: Zhijie Hou <houzj.fnst@fujitsu.com> Reviewed-by: Masahiko Sawada <sawada.mshk@gmail.com> Reviewed-by: Amit Kapila <amit.kapila16@gmail.com> Tested-by: Benoit Lobréau <benoit.lobreau@dalibo.com> Backpatch-through: 14 Discussion: https://postgr.es/m/de52b282-1166-1180-45a2-8d8917ca74c6@enterprisedb.com Discussion: https://postgr.es/m/CAD21AoAenVqiMjpN-PvGHL1N9DWnHSq673bfgr6phmBUzx=kLQ@mail.gmail.com
2025-04-08Fix uninitialized index information access during apply.Amit Kapila
The issue happens when building conflict information during apply of INSERT or UPDATE operations that violate unique constraints on leaf partitions. The problem was introduced in commit 9ff68679b5, which removed the redundant calls to ExecOpenIndices/ExecCloseIndices. The previous code was relying on the redundant ExecOpenIndices call in apply_handle_tuple_routing() to build the index information required for unique key conflict detection. The fix is to delay building the index information until a conflict is detected instead of relying on ExecOpenIndices to do the same. The additional benefit of this approach is that it avoids building index information when there is no conflict. Author: Hou Zhijie <houzj.fnst@fujitsu.com> Reviewed-by:Reviewed-by: Amit Kapila <amit.kapila16@gmail.com> Discussion: https://postgr.es/m/TYAPR01MB57244ADA33DDA57119B9D26494A62@TYAPR01MB5724.jpnprd01.prod.outlook.com
2025-04-08Flush the IO statistics of active WAL senders more frequentlyMichael Paquier
WAL senders do not flush their statistics until they exit, limiting the monitoring possible for live processes. This is penalizing when WAL senders are running for a long time, like in streaming or logical replication setups, because it is not possible to know the amount of IO they generate while running. This commit makes WAL senders more aggressive with their statistics flush, using an internal of 1 second, with the flush timing calculated based on the existing GetCurrentTimestamp() done before the sleeps done to wait for some activity. Note that the sleep done for logical and physical WAL senders happens in two different code paths, so the stats flushes need to happen in these two places. One test is added for the physical WAL sender case, and one for the logical WAL sender case. This can be done in a stable fashion by relying on the WAL generated by the TAP tests in combination with a stats reset while a server is running, but only on HEAD as WAL data has been added to pg_stat_io in a051e71e28a1. This issue exists since a9c70b46dbe and the introduction of pg_stat_io, so backpatch down to v16. Author: Bertrand Drouvot <bertranddrouvot.pg@gmail.com> Reviewed-by: vignesh C <vignesh21@gmail.com> Reviewed-by: Xuneng Zhou <xunengzhou@gmail.com> Discussion: https://postgr.es/m/Z73IsKBceoVd4t55@ip-10-97-1-34.eu-west-3.compute.internal Backpatch-through: 16
2025-04-04Use standard die() signal handler in walreceiverHeikki Linnakangas
This gets rid of the bespoken ProcessWalRcvInterrupts() function, which lets walreceiver terminate at any CHECK_FOR_INTERRUPTS() call. And it's less code anyway. We can now use the standard libpqsrv_connect_params() libpq wrapper from libpq-be-fe-helpers.h, removing more code. We attempted to do that earlier already in commit 728f86fec6, but that was reverted because it didn't call ProcessWalRcvInterrupts() and therefore didn't react to shutdown requests. Now that ProcessWalRcvInterrupts() is gone, it works. As stated in that commit, this also leads to libpqwalreceiver reserving file descriptors for libpq conncetions, which is nice. Author: Andres Freund <andres@anarazel.de> (the earlier commit) Author: Kyotaro Horiguchi <horikyota.ntt@gmail.com> Reviewed-by: Fujii Masao <masao.fujii@gmail.com> Reviewed-by: Yura Sokolov <y.sokolov@postgrespro.ru>
2025-04-03Restrict copying of invalidated replication slots.Masahiko Sawada
Previously, invalidated logical and physical replication slots could be copied using the pg_copy_logical_replication_slot and pg_copy_physical_replication_slot functions. Replication slots that were invalidated for reasons other than WAL removal retained their restart_lsn. This meant that a new slot copied from an invalidated slot could have a restart_lsn pointing to a WAL segment that might have already been removed. This commit restricts the copying of invalidated replication slots. Backpatch to v16, where slots could retain their restart_lsn when invalidated for reasons other than WAL removal. For v15 and earlier, this check is not required since slots can only be invalidated due to WAL removal, and existing checks already handle this issue. Author: Shlok Kyal <shlok.kyal.oss@gmail.com> Reviewed-by: vignesh C <vignesh21@gmail.com> Reviewed-by: Zhijie Hou <houzj.fnst@fujitsu.com> Reviewed-by: Peter Smith <smithpb2250@gmail.com> Reviewed-by: Masahiko Sawada <sawada.mshk@gmail.com> Reviewed-by: Amit Kapila <amit.kapila16@gmail.com> Discussion: https://postgr.es/m/CANhcyEU65aH0VYnLiu%3DOhNNxhnhNhwcXBeT-jvRe1OiJTo_Ayg%40mail.gmail.com Backpatch-through: 16
2025-04-03Fix slot synchronization for two_phase enabled slots.Amit Kapila
The issue is that the transactions prepared before two-phase decoding is enabled can fail to replicate to the subscriber after being committed on a promoted standby following a failover. This is because the two_phase_at field of a slot, which tracks the LSN from which two-phase decoding starts, is not synchronized to standby servers. Without two_phase_at, the logical decoding might incorrectly identify prepared transaction as already replicated to the subscriber after promotion of standby server, causing them to be skipped. To address the issue on HEAD, the two_phase_at field of the slot is exposed by the pg_replication_slots view and allows the slot synchronization to copy this value to the corresponding synced slot on the standby server. This bug is likely to occur if the user toggles the two_phase option to true after initial slot creation. Given that altering the two_phase option of a replication slot is not allowed in PostgreSQL 17, this bug is less likely to occur. We can't change the view/function definition in backbranch so we can't push the same fix but we are brainstorming an appropriate solution for PG17. Author: Zhijie Hou <houzj.fnst@fujitsu.com> Reviewed-by: Amit Kapila <amit.kapila16@gmail.com> Reviewed-by: Masahiko Sawada <sawada.mshk@gmail.com> Discussion: https://postgr.es/m/TYAPR01MB5724CC7C288535BBCEEE65DA94A72@TYAPR01MB5724.jpnprd01.prod.outlook.com
2025-03-29Use PRI?64 instead of "ll?" in format strings (continued).Peter Eisentraut
Continuation of work started in commit 15a79c73, after initial trial. Author: Thomas Munro <thomas.munro@gmail.com> Discussion: https://postgr.es/m/b936d2fb-590d-49c3-a615-92c3a88c6c19%40eisentraut.org
2025-03-27Fix guc_malloc calls for consistency and OOM checksDaniel Gustafsson
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
2025-03-26Use PG_MODULE_MAGIC_EXT in our installable shared libraries.Tom Lane
It seems potentially useful to label our shared libraries with version information, now that a facility exists for retrieving that. This patch labels them with the PG_VERSION string. There was some discussion about using semantic versioning conventions, but that doesn't seem terribly helpful for modules with no SQL-level presence; and for those that do have SQL objects, we typically expect them to support multiple revisions of the SQL definitions, so it'd still not be very helpful. I did not label any of src/test/modules/. It seems unnecessary since we don't install those, and besides there ought to be someplace that still provides test coverage for the original PG_MODULE_MAGIC macro. Author: Tom Lane <tgl@sss.pgh.pa.us> Discussion: https://postgr.es/m/dd4d1b59-d0fe-49d5-b28f-1e463b68fa32@gmail.com
2025-03-25Fix an oversight in 3abe9dc188.Amit Kapila
Forgot to update the comment atop one of the functions. Author: Hayato Kuroda <kuroda.hayato@fujitsu.com> Discussion: https://postgr.es/m/OSCPR01MB1496623BE1125B44614494E7AF5A72@OSCPR01MB14966.jpnprd01.prod.outlook.com
2025-03-24Detect and Log multiple_unique_conflicts type conflict.Amit Kapila
Introduce a new conflict type, multiple_unique_conflicts, to handle cases where an incoming row during logical replication violates multiple UNIQUE constraints. Previously, the apply worker detected and reported only the first encountered key conflict (insert_exists/update_exists), causing repeated failures as each constraint violation needs to be handled one by one making the process slow and error-prone. With this patch, the apply worker checks all unique constraints upfront once the first key conflict is detected and reports multiple_unique_conflicts if multiple violations exist. This allows users to resolve all conflicts at once by deleting all conflicting tuples rather than dealing with them individually or skipping the transaction. In the future, this will also allow us to specify different resolution handlers for such a conflict type. Add the stats for this conflict type in pg_stat_subscription_stats. Author: Nisha Moond <nisha.moond412@gmail.com> Author: Zhijie Hou <houzj.fnst@fujitsu.com> Reviewed-by: Amit Kapila <amit.kapila16@gmail.com> Reviewed-by: Peter Smith <smithpb2250@gmail.com> Reviewed-by: Dilip Kumar <dilipbalaut@gmail.com> Discussion: https://postgr.es/m/CABdArM7FW-_dnthGkg2s0fy1HhUB8C3ELA0gZX1kkbs1ZZoV3Q@mail.gmail.com