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* Split ProcSleep function into JoinWaitQueue and ProcSleepHeikki Linnakangas2024-11-04
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Split ProcSleep into two functions: JoinWaitQueue and ProcSleep. JoinWaitQueue is called while holding the partition lock, and inserts the current process to the wait queue, while ProcSleep() does the actual sleeping. ProcSleep() is now called without holding the partition lock, and it no longer re-acquires the partition lock before returning. That makes the wakeup a little cheaper. Once upon a time, re-acquiring the partition lock was needed to prevent a signal handler from longjmping out at a bad time, but these days our signal handlers just set flags, and longjmping can only happen at points where we explicitly run CHECK_FOR_INTERRUPTS(). If JoinWaitQueue detects an "early deadlock" before even joining the wait queue, it returns without changing the shared lock entry, leaving the cleanup of the shared lock entry to the caller. This makes the handling of an early deadlock the same as the dontWait=true case. One small user-visible side-effect of this refactoring is that we now only set the 'ps' title to say "waiting" when we actually enter the sleep, not when the lock is skipped because dontWait=true, or when a deadlock is detected early before entering the sleep. This eliminates the 'lockAwaited' global variable in proc.c, which was largely redundant with 'awaitedLock' in lock.c Note: Updating the local lock table is now the caller's responsibility. JoinWaitQueue and ProcSleep are now only responsible for modifying the shared state. Seems a little nicer that way. Based on Thomas Munro's earlier patch and observation that ProcSleep doesn't really need to re-acquire the partition lock. Reviewed-by: Maxim Orlov Discussion: https://www.postgresql.org/message-id/7c2090cd-a72a-4e34-afaa-6dd2ef31440e@iki.fi
* Remove unused #include's from backend .c filesPeter Eisentraut2024-10-27
| | | | | | | | as determined by IWYU These are mostly issues that are new since commit dbbca2cf299. Discussion: https://www.postgresql.org/message-id/flat/0df1d5b1-8ca8-4f84-93be-121081bde049%40eisentraut.org
* Increase the number of fast-path lock slotsTomas Vondra2024-09-21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Replace the fixed-size array of fast-path locks with arrays, sized on startup based on max_locks_per_transaction. This allows using fast-path locking for workloads that need more locks. The fast-path locking introduced in 9.2 allowed each backend to acquire a small number (16) of weak relation locks cheaply. If a backend needs to hold more locks, it has to insert them into the shared lock table. This is considerably more expensive, and may be subject to contention (especially on many-core systems). The limit of 16 fast-path locks was always rather low, because we have to lock all relations - not just tables, but also indexes, views, etc. For planning we need to lock all relations that might be used in the plan, not just those that actually get used in the final plan. So even with rather simple queries and schemas, we often need significantly more than 16 locks. As partitioning gets used more widely, and the number of partitions increases, this limit is trivial to hit. Complex queries may easily use hundreds or even thousands of locks. For workloads doing a lot of I/O this is not noticeable, but for workloads accessing only data in RAM, the access to the shared lock table may be a serious issue. This commit removes the hard-coded limit of the number of fast-path locks. Instead, the size of the fast-path arrays is calculated at startup, and can be set much higher than the original 16-lock limit. The overall fast-path locking protocol remains unchanged. The variable-sized fast-path arrays can no longer be part of PGPROC, but are allocated as a separate chunk of shared memory and then references from the PGPROC entries. The fast-path slots are organized as a 16-way set associative cache. You can imagine it as a hash table of 16-slot "groups". Each relation is mapped to exactly one group using hash(relid), and the group is then processed using linear search, just like the original fast-path cache. With only 16 entries this is cheap, with good locality. Treating this as a simple hash table with open addressing would not be efficient, especially once the hash table gets almost full. The usual remedy is to grow the table, but we can't do that here easily. The access would also be more random, with worse locality. The fast-path arrays are sized using the max_locks_per_transaction GUC. We try to have enough capacity for the number of locks specified in the GUC, using the traditional 2^n formula, with an upper limit of 1024 lock groups (i.e. 16k locks). The default value of max_locks_per_transaction is 64, which means those instances will have 64 fast-path slots. The main purpose of the max_locks_per_transaction GUC is to size the shared lock table. It is often set to the "average" number of locks needed by backends, with some backends using significantly more locks. This should not be a major issue, however. Some backens may have to insert locks into the shared lock table, but there can't be too many of them, limiting the contention. The only solution is to increase the GUC, even if the shared lock table already has sufficient capacity. That is not free, especially in terms of memory usage (the shared lock table entries are fairly large). It should only happen on machines with plenty of memory, though. In the future we may consider a separate GUC for the number of fast-path slots, but let's try without one first. Reviewed-by: Robert Haas, Jakub Wartak Discussion: https://postgr.es/m/510b887e-c0ce-4a0c-a17a-2c6abb8d9a5c@enterprisedb.com
* Add missing query ID reporting in extended query protocolMichael Paquier2024-09-18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This commit adds query ID reports for two code paths when processing extended query protocol messages: - When receiving a bind message, setting it to the first Query retrieved from a cached cache. - When receiving an execute message, setting it to the first PlannedStmt stored in a portal. An advantage of this method is that this is able to cover all the types of portals handled in the extended query protocol, particularly these two when the report done in ExecutorStart() is not enough (neither is an addition in ExecutorRun(), actually, for the second point): - Multiple execute messages, with multiple ExecutorRun(). - Portal with execute/fetch messages, like a query with a RETURNING clause and a fetch size that stores the tuples in a first execute message going though ExecutorStart() and ExecuteRun(), followed by one or more execute messages doing only fetches from the tuplestore created in the first message. This corresponds to the case where execute_is_fetch is set, for example. Note that the query ID reporting done in ExecutorStart() is still necessary, as an EXECUTE requires it. Query ID reporting is optimistic and more calls to pgstat_report_query_id() don't matter as the first report takes priority except if the report is forced. The comment in ExecutorStart() is adjusted to reflect better the reality with the extended query protocol. The test added in pg_stat_statements is a courtesy of Robert Haas. This uses psql's \bind metacommand, hence this part is backpatched down to v16. Reported-by: Kaido Vaikla, Erik Wienhold Author: Sami Imseih Reviewed-by: Jian He, Andrei Lepikhov, Michael Paquier Discussion: https://postgr.es/m/CA+427g8DiW3aZ6pOpVgkPbqK97ouBdf18VLiHFesea2jUk3XoQ@mail.gmail.com Discussion: https://postgr.es/m/CA+TgmoZxtnf_jZ=VqBSyaU8hfUkkwoJCJ6ufy4LGpXaunKrjrg@mail.gmail.com Discussion: https://postgr.es/m/1391613709.939460.1684777418070@office.mailbox.org Backpatch-through: 14
* Restrict accesses to non-system views and foreign tables during pg_dump.Masahiko Sawada2024-08-05
| | | | | | | | | | | | | | | | | | | | | | | | When pg_dump retrieves the list of database objects and performs the data dump, there was possibility that objects are replaced with others of the same name, such as views, and access them. This vulnerability could result in code execution with superuser privileges during the pg_dump process. This issue can arise when dumping data of sequences, foreign tables (only 13 or later), or tables registered with a WHERE clause in the extension configuration table. To address this, pg_dump now utilizes the newly introduced restrict_nonsystem_relation_kind GUC parameter to restrict the accesses to non-system views and foreign tables during the dump process. This new GUC parameter is added to back branches too, but these changes do not require cluster recreation. Back-patch to all supported branches. Reviewed-by: Noah Misch Security: CVE-2024-7348 Backpatch-through: 12
* Convert node test compile-time settings into run-time parametersPeter Eisentraut2024-08-01
| | | | | | | | | | | | | | | | | | | | | | | | | | | | This converts COPY_PARSE_PLAN_TREES WRITE_READ_PARSE_PLAN_TREES RAW_EXPRESSION_COVERAGE_TEST into run-time parameters debug_copy_parse_plan_trees debug_write_read_parse_plan_trees debug_raw_expression_coverage_test They can be activated for tests using PG_TEST_INITDB_EXTRA_OPTS. The compile-time symbols are kept for build farm compatibility, but they now just determine the default value of the run-time settings. Furthermore, support for these settings is not compiled in at all unless assertions are enabled, or the new symbol DEBUG_NODE_TESTS_ENABLED is defined at compile time, or any of the legacy compile-time setting symbols are defined. So there is no run-time overhead in production builds. (This is similar to the handling of DISCARD_CACHES_ENABLED.) Discussion: https://www.postgresql.org/message-id/flat/30747bd8-f51e-4e0c-a310-a6e2c37ec8aa%40eisentraut.org
* Move cancel key generation to after forking the backendHeikki Linnakangas2024-07-29
| | | | | | | | | | | | | | | | | | | | | | Move responsibility of generating the cancel key to the backend process. The cancel key is now generated after forking, and the backend advertises it in the ProcSignal array. When a cancel request arrives, the backend handling it scans the ProcSignal array to find the target pid and cancel key. This is similar to how this previously worked in the EXEC_BACKEND case with the ShmemBackendArray, just reusing the ProcSignal array. One notable change is that we no longer generate cancellation keys for non-backend processes. We generated them before just to prevent a malicious user from canceling them; the keys for non-backend processes were never actually given to anyone. There is now an explicit flag indicating whether a process has a valid key or not. I wrote this originally in preparation for supporting longer cancel keys, but it's a nice cleanup on its own. Reviewed-by: Jelte Fennema-Nio Discussion: https://www.postgresql.org/message-id/508d0505-8b7a-4864-a681-e7e5edfe32aa@iki.fi
* Use PqMsg_* macros in more places.Nathan Bossart2024-07-17
| | | | | | | | | | | Commit f4b54e1ed9, which introduced macros for protocol characters, missed updating a few places. It also did not introduce macros for messages sent from parallel workers to their leader processes. This commit adds a new section in protocol.h for those. Author: Aleksander Alekseev Discussion: https://postgr.es/m/CAJ7c6TNTd09AZq8tGaHS3LDyH_CCnpv0oOz2wN1dGe8zekxrdQ%40mail.gmail.com Backpatch-through: 17
* Remove redundant SetProcessingMode(InitProcessing) callsHeikki Linnakangas2024-07-02
| | | | | | | | | | | After several refactoring iterations, auxiliary processes are no longer initialized from the bootstrapper. Using the InitProcessing mode for initializing auxiliary processes is more appropriate. Since the global variable Mode is initialized to InitProcessing, we can just remove the redundant calls of SetProcessingMode(InitProcessing). Author: Xing Guo <higuoxing@gmail.com> Discussion: https://www.postgresql.org/message-id/CACpMh%2BDBHVT4xPGimzvex%3DwMdMLQEu9PYhT%2BkwwD2x2nu9dU_Q%40mail.gmail.com
* Preserve CurrentMemoryContext across Start/CommitTransactionCommand.Tom Lane2024-07-01
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Up to now, committing a transaction has caused CurrentMemoryContext to get set to TopMemoryContext. Most callers did not pay any particular heed to this, which is problematic because TopMemoryContext is a long-lived context that never gets reset. If the caller assumes it can leak memory because it's running in a limited-lifespan context, that behavior translates into a session-lifespan memory leak. The first-reported instance of this involved ProcessIncomingNotify, which is called from the main processing loop that normally runs in MessageContext. That outer-loop code assumes that whatever it allocates will be cleaned up when we're done processing the current client message --- but if we service a notify interrupt, then whatever gets allocated before the next switch to MessageContext will be permanently leaked in TopMemoryContext. sinval catchup interrupts have a similar problem, and I strongly suspect that some places in logical replication do too. To fix this in a generic way, let's redefine the behavior as "CommitTransactionCommand restores the memory context that was current at entry to StartTransactionCommand". This clearly fixes the issue for the notify and sinval cases, and it seems to match the mental model that's in use in the logical replication code, to the extent that anybody thought about it there at all. For consistency, likewise make subtransaction exit restore the context that was current at subtransaction start (rather than always selecting the CurTransactionContext of the parent transaction level). This case has less risk of resulting in a permanent leak than the outer-level behavior has, but it would not meet the principle of least surprise for some CommitTransactionCommand calls to restore the previous context while others don't. While we're here, also change xact.c so that we reset TopTransactionContext at transaction exit and then re-use it in later transactions, rather than dropping and recreating it in each cycle. This probably doesn't save a lot given the context recycling mechanism in aset.c, but it should save a little bit. Per suggestion from David Rowley. (Parenthetically, the text in src/backend/utils/mmgr/README implies that this is how I'd planned to implement it as far back as commit 1aebc3618 --- but the code actually added in that commit just drops and recreates it each time.) This commit also cleans up a few places outside xact.c that were needlessly making TopMemoryContext current, and thus risking more leaks of the same kind. I don't think any of them represent significant leak risks today, but let's deal with them while the issue is top-of-mind. Per bug #18512 from wizardbrony. Commit to HEAD only, as this change seems to have some risk of breaking things for some callers. We'll apply a narrower fix for the known-broken cases in the back branches. Discussion: https://postgr.es/m/3478884.1718656625@sss.pgh.pa.us
* Revise GUC names quoting in messages againPeter Eisentraut2024-05-17
| | | | | | | | | | | | | | | After further review, we want to move in the direction of always quoting GUC names in error messages, rather than the previous (PG16) wildly mixed practice or the intermittent (mid-PG17) idea of doing this depending on how possibly confusing the GUC name is. This commit applies appropriate quotes to (almost?) all mentions of GUC names in error messages. It partially supersedes a243569bf65 and 8d9978a7176, which had moved things a bit in the opposite direction but which then were abandoned in a partial state. Author: Peter Smith <smithpb2250@gmail.com> Discussion: https://www.postgresql.org/message-id/flat/CAHut%2BPv-kSN8SkxSdoHano_wPubqcg5789ejhCDZAcLFceBR-w%40mail.gmail.com
* Post-commit review fixes for slot synchronization.Amit Kapila2024-04-25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Allow pg_sync_replication_slots() to error out during promotion of standby. This makes the behavior of the SQL function consistent with the slot sync worker. We also ensured that pg_sync_replication_slots() cannot be executed if sync_replication_slots is enabled and the slotsync worker is already running to perform the synchronization of slots. Previously, it would have succeeded in cases when the worker is idle and failed when it is performing sync which could confuse users. This patch fixes another issue in the slot sync worker where SignalHandlerForShutdownRequest() needs to be registered *before* setting SlotSyncCtx->pid, otherwise, the slotsync worker could miss handling SIGINT sent by the startup process(ShutDownSlotSync) if it is sent before worker could register SignalHandlerForShutdownRequest(). To be consistent, all signal handlers' registration is moved to a prior location before we set the worker's pid. Ensure that we clean up synced temp slots at the end of pg_sync_replication_slots() to avoid such slots being left over after promotion. Ensure that ShutDownSlotSync() captures SlotSyncCtx->pid under spinlock to avoid accessing invalid value as it can be reset by concurrent slot sync exit due to an error. Author: Shveta Malik Reviewed-by: Hou Zhijie, Bertrand Drouvot, Amit Kapila, Masahiko Sawada Discussion: https://postgr.es/m/CAJpy0uBefXUS_TSz=oxmYKHdg-fhxUT0qfjASW3nmqnzVC3p6A@mail.gmail.com
* Do not output actual value of location fields in node serialization by defaultPeter Eisentraut2024-03-22
| | | | | | | | | | | | | | | | | | | This changes nodeToString() to not output the actual value of location fields in nodes, but instead it writes -1. This mirrors the fact that stringToNode() also does not read location field values but always stores -1. For most uses of nodeToString(), which is to store nodes in catalog fields, this is more useful. We don't store original query texts in catalogs, so any lingering query location values are not meaningful. For debugging purposes, there is a new nodeToStringWithLocations(), which mirrors the existing stringToNodeWithLocations(). This is used for WRITE_READ_PARSE_PLAN_TREES and nodes/print.c functions, which covers all the debugging uses. Reviewed-by: Matthias van de Meent <boekewurm+postgres@gmail.com> Discussion: https://www.postgresql.org/message-id/flat/CAEze2WgrCiR3JZmWyB0YTc8HV7ewRdx13j0CqD6mVkYAW+SFGQ@mail.gmail.com
* Fix race condition in transaction timeout TAP testsAlexander Korotkov2024-03-15
| | | | | | | | | | The interruption handler within the injection point can get stuck in an infinite loop while handling transaction timeout. To avoid this situation we reset the timeout flag before invoking the injection point. Author: Alexander Korotkov Reviewed-by: Andrey Borodin Discussion: https://postgr.es/m/ZfPchPC6oNN71X2J%40paquier.xyz
* Add TAP tests for timeoutsAlexander Korotkov2024-03-14
| | | | | | | | | | | This commit adds new tests to verify that transaction_timeout, idle_session_timeout, and idle_in_transaction_session_timeout work as expected. We introduce new injection points in before throwing a timeout FATAL error and check these injection points are reached. Discussion: https://postgr.es/m/CAAhFRxiQsRs2Eq5kCo9nXE3HTugsAAJdSQSmxncivebAxdmBjQ%40mail.gmail.com Author: Andrey Borodin Reviewed-by: Alexander Korotkov
* Move initialization of the Port struct to the child processHeikki Linnakangas2024-03-12
| | | | | | | | | | | | | | | | In postmaster, use a more lightweight ClientSocket struct that encapsulates just the socket itself and the remote endpoint's address that you get from accept() call. ClientSocket is passed to the child process, which initializes the bigger Port struct. This makes it more clear what information postmaster initializes, and what is left to the child process. Rename the StreamServerPort and StreamConnection functions to make it more clear what they do. Remove StreamClose, replacing it with plain closesocket() calls. Reviewed-by: Tristan Partin, Andres Freund Discussion: https://www.postgresql.org/message-id/7a59b073-5b5b-151e-7ed3-8b01ff7ce9ef@iki.fi
* Use MyBackendType in more places to check what process this isHeikki Linnakangas2024-03-04
| | | | | | | | | | Remove IsBackgroundWorker, IsAutoVacuumLauncherProcess(), IsAutoVacuumWorkerProcess(), and IsLogicalSlotSyncWorker() in favor of new Am*Process() macros that use MyBackendType. For consistency with the existing Am*Process() macros. Reviewed-by: Andres Freund Discussion: https://www.postgresql.org/message-id/f3ecd4cb-85ee-4e54-8278-5fabfb3a4ed0@iki.fi
* Fix typoAlvaro Herrera2024-02-21
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* Followup fixes for transaction_timeoutAlexander Korotkov2024-02-16
| | | | | | | | | | | | | Don't deal with transaction timeout in PostgresMain(). Instead, release transaction timeout activated by StartTransaction() in CommitTransaction()/AbortTransaction()/PrepareTransaction(). Deal with both enabling and disabling transaction timeout in assign_transaction_timeout(). Also, remove potentially flaky timeouts-long isolation test, which has no guarantees to pass on slow/busy machines. Reported-by: Andres Freund Discussion: https://postgr.es/m/20240215230856.pc6k57tqxt7fhldm%40awork3.anarazel.de
* Introduce transaction_timeoutAlexander Korotkov2024-02-15
| | | | | | | | | | | | | | | | | | | This commit adds timeout that is expected to be used as a prevention of long-running queries. Any session within the transaction will be terminated after spanning longer than this timeout. However, this timeout is not applied to prepared transactions. Only transactions with user connections are affected. Discussion: https://postgr.es/m/CAAhFRxiQsRs2Eq5kCo9nXE3HTugsAAJdSQSmxncivebAxdmBjQ%40mail.gmail.com Author: Andrey Borodin <amborodin@acm.org> Author: Japin Li <japinli@hotmail.com> Author: Junwang Zhao <zhjwpku@gmail.com> Reviewed-by: Nikolay Samokhvalov <samokhvalov@gmail.com> Reviewed-by: Andres Freund <andres@anarazel.de> Reviewed-by: Fujii Masao <masao.fujii@oss.nttdata.com> Reviewed-by: bt23nguyent <bt23nguyent@oss.nttdata.com> Reviewed-by: Yuhang Qiu <iamqyh@gmail.com>
* Centralize logic for restoring errno in signal handlers.Nathan Bossart2024-02-14
| | | | | | | | | | | | | | | | Presently, we rely on each individual signal handler to save the initial value of errno and then restore it before returning if needed. This is easily forgotten and, if missed, often goes undetected for a long time. In commit 3b00fdba9f, we introduced a wrapper signal handler function that checks whether MyProcPid matches getpid(). This commit moves the aforementioned errno restoration code from the individual signal handlers to the new wrapper handler so that we no longer need to worry about missing it. Reviewed-by: Andres Freund, Noah Misch Discussion: https://postgr.es/m/20231121212008.GA3742740%40nathanxps13
* Error message capitalisationPeter Eisentraut2024-01-18
| | | | | | | per style guidelines Author: Peter Smith <peter.b.smith@fujitsu.com> Discussion: https://www.postgresql.org/message-id/flat/CAHut%2BPtzstExQ4%3DvFH%2BWzZ4g4xEx2JA%3DqxussxOdxVEwJce6bw%40mail.gmail.com
* Update copyright for 2024Bruce Momjian2024-01-03
| | | | | | | | Reported-by: Michael Paquier Discussion: https://postgr.es/m/ZZKTDPxBBMt3C0J9@paquier.xyz Backpatch-through: 12
* Apply quotes more consistently to GUC names in logsMichael Paquier2023-11-30
| | | | | | | | | | | | | | Quotes are applied to GUCs in a very inconsistent way across the code base, with a mix of double quotes or no quotes used. This commit removes double quotes around all the GUC names that are obviously referred to as parameters with non-English words (use of underscore, mixed case, etc). This is the result of a discussion with Álvaro Herrera, Nathan Bossart, Laurenz Albe, Peter Eisentraut, Tom Lane and Daniel Gustafsson. Author: Peter Smith Discussion: https://postgr.es/m/CAHut+Pv-kSN8SkxSdoHano_wPubqcg5789ejhCDZAcLFceBR-w@mail.gmail.com
* Retire MemoryContextResetAndDeleteChildren() macro.Nathan Bossart2023-11-15
| | | | | | | | | | | | | | | | | As of commit eaa5808e8e, MemoryContextResetAndDeleteChildren() is just a backwards compatibility macro for MemoryContextReset(). Now that some time has passed, this macro seems more likely to create confusion. This commit removes the macro and replaces all remaining uses with calls to MemoryContextReset(). Any third-party code that use this macro will need to be adjusted to call MemoryContextReset() instead. Since the two have behaved the same way since v9.5, such adjustments won't produce any behavior changes for all currently-supported versions of PostgreSQL. Reviewed-by: Amul Sul, Tom Lane, Alvaro Herrera, Dagfinn Ilmari Mannsåker Discussion: https://postgr.es/m/20231113185950.GA1668018%40nathanxps13
* Introduce the concept of read-only StringInfosDavid Rowley2023-10-26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There were various places in our codebase which conjured up a StringInfo by manually assigning the StringInfo fields and setting the data field to point to some existing buffer. There wasn't much consistency here as to what fields like maxlen got set to and in one location we didn't correctly ensure that the buffer was correctly NUL terminated at len bytes, as per what was documented as required in stringinfo.h Here we introduce 2 new functions to initialize StringInfos. One allows callers to initialize a StringInfo passing along a buffer that is already allocated by palloc. Here the StringInfo code uses this buffer directly rather than doing any memcpying into a new allocation. Having this as a function allows us to verify the buffer is correctly NUL terminated. StringInfos initialized this way can be appended to and reset just like any other normal StringInfo. The other new initialization function also accepts an existing buffer, but the given buffer does not need to be a pointer to a palloc'd chunk. This buffer could be a pointer pointing partway into some palloc'd chunk or may not even be palloc'd at all. StringInfos initialized this way are deemed as "read-only". This means that it's not possible to append to them or reset them. For the latter of the two new initialization functions mentioned above, we relax the requirement that the data buffer must be NUL terminated. Relaxing this requirement is convenient in a few places as it can save us from having to allocate an entire new buffer just to add the NUL terminator or save us from having to temporarily add a NUL only to have to put the original char back again later. Incompatibility note: Here we also forego adding the NUL in a few places where it does not seem to be required. These locations are passing the given StringInfo into a type's receive function. It does not seem like any of our built-in receive functions require this, but perhaps there's some UDT out there in the wild which does require this. It is likely worthy of a mention in the release notes that a UDT's receive function mustn't rely on the input StringInfo being NUL terminated. Author: David Rowley Reviewed-by: Tom Lane Discussion: https://postgr.es/m/CAApHDvorfO3iBZ%3DxpiZvp3uHtJVLyFaPBSvcAhAq2HPLnaNSwQ%40mail.gmail.com
* Add support event triggers on authenticated loginAlexander Korotkov2023-10-16
| | | | | | | | | | | | | | | | | | | | | This commit introduces trigger on login event, allowing to fire some actions right on the user connection. This can be useful for logging or connection check purposes as well as for some personalization of environment. Usage details are described in the documentation included, but shortly usage is the same as for other triggers: create function returning event_trigger and then create event trigger on login event. In order to prevent the connection time overhead when there are no triggers the commit introduces pg_database.dathasloginevt flag, which indicates database has active login triggers. This flag is set by CREATE/ALTER EVENT TRIGGER command, and unset at connection time when no active triggers found. Author: Konstantin Knizhnik, Mikhail Gribkov Discussion: https://postgr.es/m/0d46d29f-4558-3af9-9c85-7774e14a7709%40postgrespro.ru Reviewed-by: Pavel Stehule, Takayuki Tsunakawa, Greg Nancarrow, Ivan Panchenko Reviewed-by: Daniel Gustafsson, Teodor Sigaev, Robert Haas, Andres Freund Reviewed-by: Tom Lane, Andrey Sokolov, Zhihong Yu, Sergey Shinderuk Reviewed-by: Gregory Stark, Nikita Malakhov, Ted Yu
* Refactor InitPostgres() to use bitwise option flagsMichael Paquier2023-10-11
| | | | | | | | | | | | | | | InitPostgres() has been using a set of boolean arguments to control its behavior, and a patch under discussion was aiming at expanding it with a third one. In preparation for expanding this area, this commit switches all the current boolean arguments of this routine to a single bits32 argument instead. Two values are currently supported for the flags: - INIT_PG_LOAD_SESSION_LIBS to load [session|local]_preload_libraries at startup. - INIT_PG_OVERRIDE_ALLOW_CONNS to allow connection to a database even if it has !datallowconn. This is used by bgworkers. Reviewed-by: Bertrand Drouvot Discussion: https://postgr.es/m/ZSTn66_BXRZCeaqS@paquier.xyz
* Fix recovery conflict SIGUSR1 handling.Thomas Munro2023-09-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We shouldn't be doing non-trivial work in signal handlers in general, and in this case the handler could reach unsafe code and corrupt state. It also clobbered its own "reason" code. Move all recovery conflict decision logic into the next CHECK_FOR_INTERRUPTS(), and have the signal handler just set flags and the latch, following the standard pattern. Since there are several different "reasons", use a separate flag for each. With this refactoring, the recovery conflict system no longer piggy-backs on top of the regular query cancelation mechanism, but instead raises an error directly if it decides that is necessary. It still needs to respect QueryCancelHoldoffCount, because otherwise the FEBE protocol might get out of sync (see commit 2b3a8b20c2d). This fixes one class of intermittent failure in the new 031_recovery_conflict.pl test added by commit 9f8a050f, though the buggy coding is much older. Failures outside contrived testing seem to be very rare (or perhaps incorrectly attributed) in the field, based on lack of reports. No back-patch for now due to complexity and release schedule. We have the option to back-patch into 16 later, as 16 has prerequisite commit bea3d7e. Reviewed-by: Andres Freund <andres@anarazel.de> (earlier version) Reviewed-by: Michael Paquier <michael@paquier.xyz> (earlier version) Reviewed-by: Robert Haas <robertmhaas@gmail.com> (earlier version) Tested-by: Christoph Berg <myon@debian.org> Discussion: https://postgr.es/m/CA%2BhUKGK3PGKwcKqzoosamn36YW-fsuTdOPPF1i_rtEO%3DnEYKSg%40mail.gmail.com Discussion: https://postgr.es/m/CALj2ACVr8au2J_9D88UfRCi0JdWhyQDDxAcSVav0B0irx9nXEg%40mail.gmail.com
* Introduce macros for protocol characters.Nathan Bossart2023-08-22
| | | | | | | | | | | This commit introduces descriptively-named macros for the identifiers used in wire protocol messages. These new macros are placed in a new header file so that they can be easily used by third-party code. Author: Dave Cramer Reviewed-by: Alvaro Herrera, Tatsuo Ishii, Peter Smith, Robert Haas, Tom Lane, Peter Eisentraut, Michael Paquier Discussion: https://postgr.es/m/CADK3HHKbBmK-PKf1bPNFoMC%2BoBt%2BpD9PH8h5nvmBQskEHm-Ehw%40mail.gmail.com
* Be more rigorous about local variables in PostgresMain().Tom Lane2023-07-10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since PostgresMain calls sigsetjmp, any local variables that are not marked "volatile" have a risk of unspecified behavior. In practice this means that when control returns via longjmp, such variables might get reset to their values as of the time of sigsetjmp, depending on whether the compiler chose to put them in registers or on the stack. We were careful about this for "send_ready_for_query", but not the other local variables. In the case of the timeout_enabled flags, resetting them to their initial "false" states is actually good, since we do "disable_all_timeouts()" in the longjmp cleanup code path. If that does not happen, we risk uselessly calling "disable_timeout()" later, which is harmless but a little bit expensive. Let's explicitly reset these flags so that the behavior is correct and platform-independent. (This change means that we really don't need the new "volatile" markings after all, but let's install them anyway since any change in this logic could re-introduce a problem.) There is no issue for "firstchar" and "input_message" because those are explicitly reinitialized each time through the query processing loop. To make that clearer, move them to be declared inside the loop. That leaves us with all the function-lifespan locals except the sigjmp_buf itself marked as volatile, which seems like a good policy to have going forward. Because of the possibility of extra disable_timeout() calls, this seems worth back-patching. Sergey Shinderuk and Tom Lane Discussion: https://postgr.es/m/2eda015b-7dff-47fd-d5e2-f1a9899b90a6@postgrespro.ru
* Message wording improvementsPeter Eisentraut2023-07-10
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* Handle logical slot conflicts on standbyAndres Freund2023-04-08
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | During WAL replay on the standby, when a conflict with a logical slot is identified, invalidate such slots. There are two sources of conflicts: 1) Using the information added in 6af1793954e, logical slots are invalidated if required rows are removed 2) wal_level on the primary server is reduced to below logical Uses the infrastructure introduced in the prior commit. FIXME: add commit reference. Change InvalidatePossiblyObsoleteSlot() to use a recovery conflict to interrupt use of a slot, if called in the startup process. The new recovery conflict is added to pg_stat_database_conflicts, as confl_active_logicalslot. See 6af1793954e for an overall design of logical decoding on a standby. Bumps catversion for the addition of the pg_stat_database_conflicts column. Bumps PGSTAT_FILE_FORMAT_ID for the same reason. Author: "Drouvot, Bertrand" <bertranddrouvot.pg@gmail.com> Author: Andres Freund <andres@anarazel.de> Author: Amit Khandekar <amitdkhan.pg@gmail.com> (in an older version) Reviewed-by: "Drouvot, Bertrand" <bertranddrouvot.pg@gmail.com> Reviewed-by: Andres Freund <andres@anarazel.de> Reviewed-by: Robert Haas <robertmhaas@gmail.com> Reviewed-by: Fabrízio de Royes Mello <fabriziomello@gmail.com> Reviewed-by: Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com> Reviewed-by: Amit Kapila <amit.kapila16@gmail.com> Reviewed-by: Alvaro Herrera <alvherre@alvh.no-ip.org> Discussion: https://postgr.es/m/20230407075009.igg7be27ha2htkbt@awork3.anarazel.de
* When using valgrind, log the current query after an error is detected.Tom Lane2023-04-03
| | | | | | | | | | | | In USE_VALGRIND builds, add code to print the text of the current query to the valgrind log whenever the valgrind error count has increased during the query. Valgrind will already have printed its report, if the error is distinct from ones already seen, so that this works out fairly well as a way of annotating the log. Onur Tirtir and Tom Lane Discussion: https://postgr.es/m/AM9PR83MB0498531E804DC8DF8CFF0E8FE9D09@AM9PR83MB0498.EURPRD83.prod.outlook.com
* Speedup and increase usability of set proc title functionsDavid Rowley2023-02-20
| | | | | | | | | | | | | | | | | | | | | | The setting of the process title could be seen on profiles of very fast-to-execute queries. In many locations where we call set_ps_display() we pass along a string constant, the length of which is known during compilation. Here we effectively rename set_ps_display() to set_ps_display_with_len() and then add a static inline function named set_ps_display() which calls strlen() on the given string. This allows the compiler to optimize away the strlen() call when dealing with call sites passing a string constant. We can then also use memcpy() instead of strlcpy() to copy the string into the destination buffer. That's significantly faster than strlcpy's byte-at-a-time way of copying. Here we also take measures to improve some code which was adjusting the process title to add a " waiting" suffix to it. Call sites which require this can now just call set_ps_display_suffix() to add or adjust the suffix and call set_ps_display_remove_suffix() to remove it again. Reviewed-by: Andres Freund Discussion: https://postgr.es/m/CAApHDvocBvvk-0gWNA2Gohe+sv9fMcv+fK_G+siBKJrgDG4O7g@mail.gmail.com
* Retire PG_SETMASK() macro.Thomas Munro2023-02-03
| | | | | | | | | | | | | | | | In the 90s we needed to deal with computers that still had the pre-standard signal masking APIs. That hasn't been relevant for a very long time on Unix systems, and c94ae9d8 got rid of a remaining dependency in our Windows porting code. PG_SETMASK didn't expose save/restore functionality, so we'd already started using sigprocmask() directly in places, creating the visual distraction of having two ways to spell it. It's not part of the API that extensions are expected to be using (but if they are, the change will be trivial). It seems like a good time to drop the old macro and just call the standard POSIX function. Reviewed-by: Nathan Bossart <nathandbossart@gmail.com> Discussion: https://postgr.es/m/CA%2BhUKG%2BKfQgrhHP2DLTohX1WwubaCBHmTzGnAEDPZ-Gug-Xskg%40mail.gmail.com
* Use WaitEventSet API for postmaster's event loop.Thomas Munro2023-01-12
| | | | | | | | | | | | | | | | | | | | | | Switch to a design similar to regular backends, instead of the previous arrangement where signal handlers did non-trivial state management and called fork(). The main changes are: * The postmaster now has its own local latch to wait on. (For now, we don't want other backends setting its latch directly, but that could probably be made to work with more research on robustness.) * The existing signal handlers are cut in two: a handle_pm_XXX() part that just sets pending_pm_XXX flags and the latch, and a process_pm_XXX() part that runs later when the latch is seen. * Signal handlers are now installed with the regular pqsignal() function rather than the special pqsignal_pm() function; historical portability concerns about the effect of SA_RESTART on select() are no longer relevant, and we don't need to block signals anymore. Reviewed-by: Andres Freund <andres@anarazel.de> Discussion: https://postgr.es/m/CA%2BhUKG%2BZ-HpOj1JsO9eWUP%2Bar7npSVinsC_npxSy%2BjdOMsx%3DGg%40mail.gmail.com
* Perform apply of large transactions by parallel workers.Amit Kapila2023-01-09
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, for large transactions, the publisher sends the data in multiple streams (changes divided into chunks depending upon logical_decoding_work_mem), and then on the subscriber-side, the apply worker writes the changes into temporary files and once it receives the commit, it reads from those files and applies the entire transaction. To improve the performance of such transactions, we can instead allow them to be applied via parallel workers. In this approach, we assign a new parallel apply worker (if available) as soon as the xact's first stream is received and the leader apply worker will send changes to this new worker via shared memory. The parallel apply worker will directly apply the change instead of writing it to temporary files. However, if the leader apply worker times out while attempting to send a message to the parallel apply worker, it will switch to "partial serialize" mode - in this mode, the leader serializes all remaining changes to a file and notifies the parallel apply workers to read and apply them at the end of the transaction. We use a non-blocking way to send the messages from the leader apply worker to the parallel apply to avoid deadlocks. We keep this parallel apply assigned till the transaction commit is received and also wait for the worker to finish at commit. This preserves commit ordering and avoid writing to and reading from files in most cases. We still need to spill if there is no worker available. This patch also extends the SUBSCRIPTION 'streaming' parameter so that the user can control whether to apply the streaming transaction in a parallel apply worker or spill the change to disk. The user can set the streaming parameter to 'on/off', or 'parallel'. The parameter value 'parallel' means the streaming will be applied via a parallel apply worker, if available. The parameter value 'on' means the streaming transaction will be spilled to disk. The default value is 'off' (same as current behaviour). In addition, the patch extends the logical replication STREAM_ABORT message so that abort_lsn and abort_time can also be sent which can be used to update the replication origin in parallel apply worker when the streaming transaction is aborted. Because this message extension is needed to support parallel streaming, parallel streaming is not supported for publications on servers < PG16. Author: Hou Zhijie, Wang wei, Amit Kapila with design inputs from Sawada Masahiko Reviewed-by: Sawada Masahiko, Peter Smith, Dilip Kumar, Shi yu, Kuroda Hayato, Shveta Mallik Discussion: https://postgr.es/m/CAA4eK1+wyN6zpaHUkCLorEWNx75MG0xhMwcFhvjqm2KURZEAGw@mail.gmail.com
* Update copyright for 2023Bruce Momjian2023-01-02
| | | | Backpatch-through: 11
* 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
* Order getopt argumentsPeter Eisentraut2022-12-12
| | | | | | | | | | Order the letters in the arguments of getopt() and getopt_long(), as well as in the subsequent switch statements. In most cases, I used alphabetical with lower case first. In a few cases, existing different orders (e.g., upper case first) was kept to reduce the diff size. Discussion: https://www.postgresql.org/message-id/flat/3efd0fe8-351b-f836-9122-886002602357%40enterprisedb.com
* Remove AssertArg and AssertStatePeter Eisentraut2022-10-28
| | | | | | | | | These don't offer anything over plain Assert, and their usage had already been declared obsolescent. Author: Nathan Bossart <nathandbossart@gmail.com> Reviewed-by: Michael Paquier <michael@paquier.xyz> Discussion: https://www.postgresql.org/message-id/20221009210148.GA900071@nathanxps13
* Store GUC data in a memory context, instead of using malloc().Tom Lane2022-10-14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | The only real argument for using malloc directly was that we needed the ability to not throw error on OOM; but mcxt.c grew that feature awhile ago. Keeping the data in a memory context improves accountability and debuggability --- for example, without this it's almost impossible to detect memory leaks in the GUC code with anything less costly than valgrind. Moreover, the next patch in this series will add a hash table for GUC lookup, and it'd be pretty silly to be using palloc-dependent hash facilities alongside malloc'd storage of the underlying data. This is a bit invasive though, in particular causing an API break for GUC check hooks that want to modify the GUC's value or use an "extra" data structure. They must now use guc_malloc() and guc_free() instead of malloc() and free(). Failure to change affected code will result in assertion failures or worse; but thanks to recent effort in the mcxt infrastructure, it shouldn't be too hard to diagnose such oversights (at least in assert-enabled builds). One note is that this changes ParseLongOption() to return short-lived palloc'd not malloc'd data. There wasn't any caller for which the previous definition was better. Discussion: https://postgr.es/m/2982579.1662416866@sss.pgh.pa.us
* Fix shadow variable in postgres.cMichael Paquier2022-10-12
| | | | | | | | -Wshadow=compatible-local is added by default since 0fe954c, and this warning was detected under -DWRITE_READ_PARSE_PLAN_TREES. Reviewed-by: David Rowley Discussion: https://postgr.es/m/Y0Ya5SH0QiaO9kKG@paquier.xyz
* Enable WRITE_READ_PARSE_PLAN_TREES of rewritten utility statementsTom Lane2022-09-26
| | | | | | | | This was previously disabled because we lacked outfuncs/readfuncs support for most utility statement types. Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us> Discussion: https://www.postgresql.org/message-id/flat/4159834.1657405226@sss.pgh.pa.us
* Implement WRITE_READ_PARSE_PLAN_TREES for raw parse treesTom Lane2022-09-26
| | | | | Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us> Discussion: https://www.postgresql.org/message-id/flat/4159834.1657405226@sss.pgh.pa.us
* Split up guc.c for better build speed and ease of maintenance.Tom Lane2022-09-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | guc.c has grown to be one of our largest .c files, making it a bottleneck for compilation. It's also acquired a bunch of knowledge that'd be better kept elsewhere, because of our not very good habit of putting variable-specific check hooks here. Hence, split it up along these lines: * guc.c itself retains just the core GUC housekeeping mechanisms. * New file guc_funcs.c contains the SET/SHOW interfaces and some SQL-accessible functions for GUC manipulation. * New file guc_tables.c contains the data arrays that define the built-in GUC variables, along with some already-exported constant tables. * GUC check/assign/show hook functions are moved to the variable's home module, whenever that's clearly identifiable. A few hard- to-classify hooks ended up in commands/variable.c, which was already a home for miscellaneous GUC hook functions. To avoid cluttering a lot more header files with #include "guc.h", I also invented a new header file utils/guc_hooks.h and put all the GUC hook functions' declarations there, regardless of their originating module. That allowed removal of #include "guc.h" from some existing headers. The fallout from that (hopefully all caught here) demonstrates clearly why such inclusions are best minimized: there are a lot of files that, for example, were getting array.h at two or more levels of remove, despite not having any connection at all to GUCs in themselves. There is some very minor code beautification here, such as renaming a couple of inconsistently-named hook functions and improving some comments. But mostly this just moves code from point A to point B and deals with the ensuing needs for #include adjustments and exporting a few functions that previously weren't exported. Patch by me, per a suggestion from Andres Freund; thanks also to Michael Paquier for the idea to invent guc_funcs.c. Discussion: https://postgr.es/m/587607.1662836699@sss.pgh.pa.us
* Assorted examples of expanded type-safer palloc/pg_malloc APIPeter Eisentraut2022-09-12
| | | | | | | | | This adds some uses of the new palloc/pg_malloc variants here and there as a demonstration and test. This is kept separate from the actual API patch, since the latter might be backpatched at some point. Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us> Discussion: https://www.postgresql.org/message-id/flat/bb755632-2a43-d523-36f8-a1e7a389a907@enterprisedb.com
* Remove configure probe for sys/resource.h and refactor.Thomas Munro2022-08-14
| | | | | | | | | | | | <sys/resource.h> is in SUSv2 and is on all targeted Unix systems. We have a replacement for getrusage() on Windows, so let's just move its declarations into src/include/port/win32/sys/resource.h so that we can use a standard-looking #include. Also remove an obsolete reference to CLK_TCK. Also rename src/port/getrusage.c to win32getrusage.c, following the convention for Windows-only fallback code. Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us> Discussion: https://postgr.es/m/CA%2BhUKG%2BL_3brvh%3D8e0BW_VfX9h7MtwgN%3DnFHP5o7X2oZucY9dg%40mail.gmail.com
* Remove configure probe for sys/select.h.Thomas Munro2022-08-14
| | | | | | | | | <sys/select.h> is in SUSv3 and every targeted Unix system has it. Provide an empty header in src/include/port/win32 so that we can include it unguarded even on Windows. Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us> Discussion: https://postgr.es/m/CA%2BhUKG%2BL_3brvh%3D8e0BW_VfX9h7MtwgN%3DnFHP5o7X2oZucY9dg%40mail.gmail.com