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* Add HINT for restartpoint race with KeepFileRestoredFromArchive().Noah Misch2022-08-05
| | | | | | | | | | The five commits ending at cc2c7d65fc27e877c9f407587b0b92d46cd6dd16 closed this race condition for v15+. For v14 through v10, add a HINT to discourage studying the cosmetic problem. Reviewed by Kyotaro Horiguchi and David Steele. Discussion: https://postgr.es/m/20220731061747.GA3692882@rfd.leadboat.com
* Don't Insert() a VFD entry until it's fully built.Tom Lane2020-11-16
| | | | | | | | | | | | | | | | | | | Otherwise, if FDDEBUG is enabled, the debugging output fails because it tries to read the fileName, which isn't set up yet (and should in fact always be NULL). AFAICT, this has been wrong since Berkeley. Before 96bf88d52, it would accidentally fail to crash on platforms where snprintf() is forgiving about being passed a NULL pointer for %s; but the file name intended to be included in the debug output wouldn't ever have shown up. Report and fix by Greg Nancarrow. Although this is only visibly broken in custom-made builds, it still seems worth back-patching to all supported branches, as the FDDEBUG code is pretty useless as it stands. Discussion: https://postgr.es/m/CAJcOf-cUDgm9qYtC_B6XrC6MktMPNRby2p61EtSGZKnfotMArw@mail.gmail.com
* Fix temporary tablespaces for shared filesets some more.Tom Lane2020-07-03
| | | | | | | | | | | | | | | | | | | | | | | | Commit ecd9e9f0b fixed the problem in the wrong place, causing unwanted side-effects on the behavior of GetNextTempTableSpace(). Instead, let's make SharedFileSetInit() responsible for subbing in the value of MyDatabaseTableSpace when the default tablespace is called for. The convention about what is in the tempTableSpaces[] array is evidently insufficiently documented, so try to improve that. It also looks like SharedFileSetInit() is doing the wrong thing in the case where temp_tablespaces is empty. It was hard-wiring use of the pg_default tablespace, but it seems like using MyDatabaseTableSpace is more consistent with what happens for other temp files. Back-patch the reversion of PrepareTempTablespaces()'s behavior to 9.5, as ecd9e9f0b was. The changes in SharedFileSetInit() go back to v11 where that was introduced. (Note there is net zero code change before v11 from these two patch sets, so nothing to release-note.) Magnus Hagander and Tom Lane Discussion: https://postgr.es/m/CABUevExg5YEsOvqMxrjoNvb3ApVyH+9jggWGKwTDFyFCVWczGQ@mail.gmail.com
* Message style fixesPeter Eisentraut2019-09-23
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* Fix more typos and inconsistencies in the treeMichael Paquier2019-06-17
| | | | | Author: Alexander Lakhin Discussion: https://postgr.es/m/0a5419ea-1452-a4e6-72ff-545b1a5a8076@gmail.com
* Phase 2 pgindent run for v12.Tom Lane2019-05-22
| | | | | | | | | Switch to 2.1 version of pg_bsd_indent. This formats multiline function declarations "correctly", that is with additional lines of parameter declarations indented to match where the first line's left parenthesis is. Discussion: https://postgr.es/m/CAEepm=0P3FeTXRcU5B2W3jv3PgRVZ-kGUXLGfd42FFhUROO3ug@mail.gmail.com
* Initial pgindent run for v12.Tom Lane2019-05-22
| | | | | | | | This is still using the 2.0 version of pg_bsd_indent. I thought it would be good to commit this separately, so as to document the differences between 2.0 and 2.1 behavior. Discussion: https://postgr.es/m/16296.1558103386@sss.pgh.pa.us
* Tighten use of OpenTransientFile and CloseTransientFileMichael Paquier2019-03-09
| | | | | | | | | | | | | | | | | | | | | | | | | | This fixes two sets of issues related to the use of transient files in the backend: 1) OpenTransientFile() has been used in some code paths with read-write flags while read-only is sufficient, so switch those calls to be read-only where necessary. These have been reported by Joe Conway. 2) When opening transient files, it is up to the caller to close the file descriptors opened. In error code paths, CloseTransientFile() gets called to clean up things before issuing an error. However in normal exit paths, a lot of callers of CloseTransientFile() never actually reported errors, which could leave a file descriptor open without knowing about it. This is an issue I complained about a couple of times, but never had the courage to write and submit a patch, so here we go. Note that one frontend code path is impacted by this commit so as an error is issued when fetching control file data, making backend and frontend to be treated consistently. Reported-by: Joe Conway, Michael Paquier Author: Michael Paquier Reviewed-by: Álvaro Herrera, Georgios Kokolatos, Joe Conway Discussion: https://postgr.es/m/20190301023338.GD1348@paquier.xyz Discussion: https://postgr.es/m/c49b69ec-e2f7-ff33-4f17-0eaa4f2cef27@joeconway.com
* Tolerate EINVAL when calling fsync() on a directory.Thomas Munro2019-02-24
| | | | | | | | | | | Previously, we tolerated EBADF as a way for the operating system to indicate that it doesn't support fsync() on a directory. Tolerate EINVAL too, for older versions of Linux CIFS. Bug #15636. Back-patch all the way. Reported-by: John Klann Discussion: https://postgr.es/m/15636-d380890dafd78fc6@postgresql.org
* Tolerate ENOSYS failure from sync_file_range().Thomas Munro2019-02-24
| | | | | | | | | | | | | | | | | | | | | One unintended consequence of commit 9ccdd7f6 was that Windows WSL users started getting a panic whenever we tried to initiate data flushing with sync_file_range(), because WSL does not implement that system call. Previously, they got a stream of periodic warnings, which was also undesirable but at least ignorable. Prevent the panic by handling ENOSYS specially and skipping the panic promotion with data_sync_elevel(). Also suppress future attempts after the first such failure so that the pre-existing problem of noisy warnings is improved. Back-patch to 9.6 (older branches were not affected in this way by 9ccdd7f6). Author: Thomas Munro and James Sewell Tested-by: James Sewell Reported-by: Bruce Klein Discussion: https://postgr.es/m/CA+mCpegfOUph2U4ZADtQT16dfbkjjYNJL1bSTWErsazaFjQW9A@mail.gmail.com
* Update copyright for 2019Bruce Momjian2019-01-02
| | | | Backpatch-through: certain files through 9.4
* Handle EPIPE more sanely when we close a pipe reading from a program.Tom Lane2018-11-19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Previously, any program launched by COPY TO/FROM PROGRAM inherited the server's setting of SIGPIPE handling, i.e. SIG_IGN. Hence, if we were doing COPY FROM PROGRAM and closed the pipe early, the child process would see EPIPE on its output file and typically would treat that as a fatal error, in turn causing the COPY to report error. Similarly, one could get a failure report from a query that didn't read all of the output from a contrib/file_fdw foreign table that uses file_fdw's PROGRAM option. To fix, ensure that child programs inherit SIG_DFL not SIG_IGN processing of SIGPIPE. This seems like an all-around better situation since if the called program wants some non-default treatment of SIGPIPE, it would expect to have to set that up for itself. Then in COPY, if it's COPY FROM PROGRAM and we stop reading short of detecting EOF, treat a SIGPIPE exit from the called program as a non-error condition. This still allows us to report an error for any case where the called program gets SIGPIPE on some other file descriptor. As coded, we won't report a SIGPIPE if we stop reading as a result of seeing an in-band EOF marker (e.g. COPY BINARY EOF marker). It's somewhat debatable whether we should complain if the called program continues to transmit data after an EOF marker. However, it seems like we should avoid throwing error in any questionable cases, especially in a back-patched fix, and anyway it would take additional code to make such an error get reported consistently. Back-patch to v10. We could go further back, since COPY FROM PROGRAM has been around awhile, but AFAICS the only way to reach this situation using core or contrib is via file_fdw, which has only supported PROGRAM sources since v10. The COPY statement per se has no feature whereby it'd stop reading without having hit EOF or an error already. Therefore, I don't see any upside to back-patching further that'd outweigh the risk of complaints about behavioral change. Per bug #15449 from Eric Cyr. Patch by me, review by Etsuro Fujita and Kyotaro Horiguchi Discussion: https://postgr.es/m/15449-1cf737dd5929450e@postgresql.org
* PANIC on fsync() failure.Thomas Munro2018-11-19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On some operating systems, it doesn't make sense to retry fsync(), because dirty data cached by the kernel may have been dropped on write-back failure. In that case the only remaining copy of the data is in the WAL. A subsequent fsync() could appear to succeed, but not have flushed the data. That means that a future checkpoint could apparently complete successfully but have lost data. Therefore, violently prevent any future checkpoint attempts by panicking on the first fsync() failure. Note that we already did the same for WAL data; this change extends that behavior to non-temporary data files. Provide a GUC data_sync_retry to control this new behavior, for users of operating systems that don't eject dirty data, and possibly forensic/testing uses. If it is set to on and the write-back error was transient, a later checkpoint might genuinely succeed (on a system that does not throw away buffers on failure); if the error is permanent, later checkpoints will continue to fail. The GUC defaults to off, meaning that we panic. Back-patch to all supported releases. There is still a narrow window for error-loss on some operating systems: if the file is closed and later reopened and a write-back error occurs in the intervening time, but the inode has the bad luck to be evicted due to memory pressure before we reopen, we could miss the error. A later patch will address that with a scheme for keeping files with dirty data open at all times, but we judge that to be too complicated to back-patch. Author: Craig Ringer, with some adjustments by Thomas Munro Reported-by: Craig Ringer Reviewed-by: Robert Haas, Thomas Munro, Andres Freund Discussion: https://postgr.es/m/20180427222842.in2e4mibx45zdth5%40alap3.anarazel.de
* Remove set-but-unused variable.Thomas Munro2018-11-07
| | | | | | | Clean-up for commit c24dcd0c. Reported-by: Andrew Dunstan Discussion: https://postgr.es/m/2d52ff4a-5440-f6f1-7806-423b0e6370cb%402ndQuadrant.com
* Use pg_pread() and pg_pwrite() for data files and WAL.Thomas Munro2018-11-07
| | | | | | | | | | | | | Cut down on system calls by doing random I/O using offset-based OS routines where available. Remove the code for tracking the 'virtual' seek position. The only reason left to call FileSeek() was to get the file's size, so provide a new function FileSize() instead. Author: Oskari Saarenmaa, Thomas Munro Reviewed-by: Thomas Munro, Jesper Pedersen, Tom Lane, Alvaro Herrera Discussion: https://postgr.es/m/CAEepm=02rapCpPR3ZGF2vW=SBHSdFYO_bz_f-wwWJonmA3APgw@mail.gmail.com Discussion: https://postgr.es/m/b8748d39-0b19-0514-a1b9-4e5a28e6a208%40gmail.com Discussion: https://postgr.es/m/a86bd200-ebbe-d829-e3ca-0c4474b2fcb7%40ohmu.fi
* Fix incorrect ordering of operations in pg_resetwal and pg_rewind.Tom Lane2018-05-23
| | | | | | | | | | | | | | | | | | | | | Commit c37b3d08c dropped its added GetDataDirectoryCreatePerm call into the wrong place in pg_resetwal.c, namely after the chdir to DataDir. That broke invocations using a relative path, as reported by Tushar Ahuja. We could have left it where it was and changed the argument to be ".", but that'd result in a rather confusing error message in event of a failure, so re-ordering seems like a better solution. Similarly reorder operations in pg_rewind.c. The issue there is that it doesn't seem like a good idea to do any actual operations before the not-root check (on Unix) or the restricted token acquisition (on Windows). I don't know that this is an actual bug, but I'm definitely not convinced that it isn't, either. Assorted other code review for c37b3d08c and da9b580d8: fix some misspelled or otherwise badly worded comments, put the #include for <sys/stat.h> where it actually belongs, etc. Discussion: https://postgr.es/m/aeb9c3a7-3c3f-a57f-1a18-c8d4fcdc2a1f@enterprisedb.com
* Fix some sloppiness in the new BufFileSize() and BufFileAppend() functions.Heikki Linnakangas2018-05-02
| | | | | | | | | | | | | | | | | | | | | There were three related issues: * BufFileAppend() incorrectly reset the seek position on the 'source' file. As a result, if you had called BufFileRead() on the file before calling BufFileAppend(), it got confused, and subsequent calls would read/write at wrong position. * BufFileSize() did not work with files opened with BufFileOpenShared(). * FileGetSize() only worked on temporary files. To fix, change the way BufFileSize() works so that it works on shared files. Remove FileGetSize() altogether, as it's no longer needed. Remove buffilesize from TapeShare struct, as the leader process can simply call BufFileSize() to get the tape's size, there's no need to pass it through shared memory anymore. Discussion: https://www.postgresql.org/message-id/CAH2-WznEDYe_NZXxmnOfsoV54oFkTdMy7YLE2NPBLuttO96vTQ@mail.gmail.com
* In AtEOXact_Files, complain if any files remain unclosed at commit.Tom Lane2018-04-28
| | | | | | | | | | | This change makes this module act more like most of our other low-level resource management modules. It's a caller error if something is not explicitly closed by the end of a successful transaction, so issue a WARNING about it. This would not actually have caught the file leak bug fixed in commit 231bcd080, because that was in a transaction-abort path; but it still seems like a good, and pretty cheap, cross-check. Discussion: https://postgr.es/m/152056616579.4966.583293218357089052@wrigleys.postgresql.org
* Further cleanup of client dependencies on src/include/catalog headers.Tom Lane2018-04-09
| | | | | | | | | | | | | | | | | In commit 9c0a0de4c, I'd failed to notice that catalog/catalog.h should also be considered a frontend-unsafe header, because it includes (and needs) the full form of pg_class.h, not to mention relcache.h. However, various frontend code was depending on it to get TABLESPACE_VERSION_DIRECTORY, so refactoring of some sort is called for. The cleanest answer seems to be to move TABLESPACE_VERSION_DIRECTORY, as well as the OIDCHARS symbol, to common/relpath.h. Do that, and mop up inclusions as necessary. (I found that quite a few current users of catalog/catalog.h don't seem to need it at all anymore, apparently as a result of the refactorings that created common/relpath.[hc]. And initdb.c needed it only as a route to pg_class_d.h.) Discussion: https://postgr.es/m/6629.1523294509@sss.pgh.pa.us
* Refactor dir/file permissionsStephen Frost2018-04-07
| | | | | | | | | | | | | | | | | | | Consolidate directory and file create permissions for tools which work with the PG data directory by adding a new module (common/file_perm.c) that contains variables (pg_file_create_mode, pg_dir_create_mode) and constants to initialize them (0600 for files and 0700 for directories). Convert mkdir() calls in the backend to MakePGDirectory() if the original call used default permissions (always the case for regular PG directories). Add tests to make sure permissions in PGDATA are set correctly by the tools which modify the PG data directory. Authors: David Steele <david@pgmasters.net>, Adam Brightwell <adam.brightwell@crunchydata.com> Reviewed-By: Michael Paquier, with discussion amongst many others. Discussion: https://postgr.es/m/ad346fe6-b23e-59f1-ecb7-0e08390ad629%40pgmasters.net
* Skip temp tables from basebackup.Teodor Sigaev2018-03-27
| | | | | | | | | Do not store temp tables in basebackup, they will not be visible anyway, so, there are not reasons to store them. Author: David Steel Reviewed by: me Discussion: https://www.postgresql.org/message-id/flat/5ea4d26a-a453-c1b7-eff9-5a3ef8f8aceb@pgmasters.net
* Support parallel btree index builds.Robert Haas2018-02-02
| | | | | | | | | | | | | | | | | | | | | | To make this work, tuplesort.c and logtape.c must also support parallelism, so this patch adds that infrastructure and then applies it to the particular case of parallel btree index builds. Testing to date shows that this can often be 2-3x faster than a serial index build. The model for deciding how many workers to use is fairly primitive at present, but it's better than not having the feature. We can refine it as we get more experience. Peter Geoghegan with some help from Rushabh Lathia. While Heikki Linnakangas is not an author of this patch, he wrote other patches without which this feature would not have been possible, and therefore the release notes should possibly credit him as an author of this feature. Reviewed by Claudio Freire, Heikki Linnakangas, Thomas Munro, Tels, Amit Kapila, me. Discussion: http://postgr.es/m/CAM3SWZQKM=Pzc=CAHzRixKjp2eO5Q0Jg1SoFQqeXFQ647JiwqQ@mail.gmail.com Discussion: http://postgr.es/m/CAH2-Wz=AxWqDoVvGU7dq856S4r6sJAj6DBn7VMtigkB33N5eyg@mail.gmail.com
* Back off chattiness in RemovePgTempFiles().Tom Lane2018-01-07
| | | | | | | | | | | | | | In commit 561885db0, as part of normalizing RemovePgTempFiles's error handling, I removed its behavior of silently ignoring ENOENT failures during directory opens. Thomas Munro points out that this is a bad idea at the top level, because we don't create pgsql_tmp directories until needed. Thus this coding could produce LOG messages in perfectly normal situations, which isn't what I intended. Restore the suppression of ENOENT logging, but only at top level --- it would still be unexpected for a nested temp directory to disappear between seeing it in the parent directory and opening it. Discussion: https://postgr.es/m/CAEepm=2y06SehAkTnd5sU_eVqdv5P-=Srt1y5vYNQk6yVDVaPw@mail.gmail.com
* Update copyright for 2018Bruce Momjian2018-01-02
| | | | Backpatch-through: certain files through 9.3
* Fix race-under-concurrency in PathNameCreateTemporaryDir.Robert Haas2017-12-27
| | | | | | Thomas Munro Discussion: http://postgr.es/m/CAEepm=1Vp1e3KtftLtw4B60ZV9teNeKu6HxoaaBptQMsRWjJbQ@mail.gmail.com
* Improve error handling in RemovePgTempFiles().Tom Lane2017-12-04
| | | | | | | | | | | | | | | | | | | | | | | | Modify this function and its subsidiaries so that syscall failures are reported via ereport(LOG), rather than silently ignored as before. We don't want to throw a hard ERROR, as that would prevent database startup, and getting rid of leftover temporary files is not important enough for that. On the other hand, not reporting trouble at all seems like an odd choice not in line with current project norms, especially since any failure here is quite unexpected. On the same reasoning, adjust these functions' AllocateDir/ReadDir calls so that failure to scan a directory results in LOG not ERROR. I also removed the previous practice of silently ignoring ENOENT failures during directory opens --- there are some corner cases where that could happen given a previous database crash, but that seems like a bad excuse for ignoring a condition that isn't expected in most cases. A LOG message during postmaster start seems OK in such situations, and better than no output at all. In passing, make RemovePgTempRelationFiles' test for "is the file name all digits" look more like the way it's done elsewhere. Discussion: https://postgr.es/m/19907.1512402254@sss.pgh.pa.us
* Clean up assorted messiness around AllocateDir() usage.Tom Lane2017-12-04
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch fixes a couple of low-probability bugs that could lead to reporting an irrelevant errno value (and hence possibly a wrong SQLSTATE) concerning directory-open or file-open failures. It also fixes places where we took shortcuts in reporting such errors, either by using elog instead of ereport or by using ereport but forgetting to specify an errcode. And it eliminates a lot of just plain redundant error-handling code. In service of all this, export fd.c's formerly-static function ReadDirExtended, so that external callers can make use of the coding pattern dir = AllocateDir(path); while ((de = ReadDirExtended(dir, path, LOG)) != NULL) if they'd like to treat directory-open failures as mere LOG conditions rather than errors. Also fix FreeDir to be a no-op if we reach it with dir == NULL, as such a coding pattern would cause. Then, remove code at many call sites that was throwing an error or log message for AllocateDir failure, as ReadDir or ReadDirExtended can handle that job just fine. Aside from being a net code savings, this gets rid of a lot of not-quite-up-to-snuff reports, as mentioned above. (In some places these changes result in replacing a custom error message such as "could not open tablespace directory" with more generic wording "could not open directory", but it was agreed that the custom wording buys little as long as we report the directory name.) In some other call sites where we can't just remove code, change the error reports to be fully project-style-compliant. Also reorder code in restoreTwoPhaseData that was acquiring a lock between AllocateDir and ReadDir; in the unlikely but surely not impossible case that LWLockAcquire changes errno, AllocateDir failures would be misreported. There is no great value in opening the directory before acquiring TwoPhaseStateLock, so just do it in the other order. Also fix CheckXLogRemoved to guarantee that it preserves errno, as quite a number of call sites are implicitly assuming. (Again, it's unlikely but I think not impossible that errno could change during a SpinLockAcquire. If so, this function was broken for its own purposes as well as breaking callers.) And change a few places that were using not-per-project-style messages, such as "could not read directory" when "could not open directory" is more correct. Back-patch the exporting of ReadDirExtended, in case we have occasion to back-patch some fix that makes use of it; it's not needed right now but surely making it global is pretty harmless. Also back-patch the restoreTwoPhaseData and CheckXLogRemoved fixes. The rest of this is essentially cosmetic and need not get back-patched. Michael Paquier, with a bit of additional work by me Discussion: https://postgr.es/m/CAB7nPqRpOCxjiirHmebEFhXVTK7V5Jvw4bz82p7Oimtsm3TyZA@mail.gmail.com
* Adjust #ifdef EXEC_BACKEND RemovePgTempFilesInDir() call.Andres Freund2017-12-01
| | | | | | | Other callers were adjusted in the course of dc6c4c9dc2a111519b76b22daaaac86c5608223b. Per buildfarm.
* Add infrastructure for sharing temporary files between backends.Andres Freund2017-12-01
| | | | | | | | | | | | | | | | | SharedFileSet allows temporary files to be created by one backend and then exported for read-only access by other backends, with clean-up managed by reference counting associated with a DSM segment. This includes changes to fd.c and buffile.c to support the new kind of temporary file. This will be used by an upcoming patch adding support for parallel hash joins. Author: Thomas Munro Reviewed-By: Peter Geoghegan, Andres Freund, Robert Haas, Rushabh Lathia Discussion: https://postgr.es/m/CAEepm=2W=cOkiZxcg6qiFQP-dHUe09aqTrEMM7yJDrHMhDv_RA@mail.gmail.com https://postgr.es/m/CAH2-WznJ_UgLux=_jTgCQ4yFz0iBntudsNKa1we3kN1BAG=88w@mail.gmail.com
* Fix two violations of the ResourceOwnerEnlarge/Remember protocol.Tom Lane2017-11-08
| | | | | | | | | | | | | | | | | | | | | The point of having separate ResourceOwnerEnlargeFoo and ResourceOwnerRememberFoo functions is so that resource allocation can happen in between. Doing it in some other order is just wrong. OpenTemporaryFile() did open(), enlarge, remember, which would leak the open file if the enlarge step ran out of memory. Because fd.c has its own layer of resource-remembering, the consequences look like they'd be limited to an intratransaction FD leak, but it's still not good. IncrBufferRefCount() did enlarge, remember, incr-refcount, which would blow up if the incr-refcount step ever failed. It was safe enough when written, but since the introduction of PrivateRefCountHash, I think the assumption that no error could happen there is pretty shaky. The odds of real problems from either bug are probably small, but still, back-patch to supported branches. Thomas Munro and Tom Lane, per a comment from Andres Freund
* Change TRUE/FALSE to true/falsePeter Eisentraut2017-11-08
| | | | | | | | | | | | | | The lower case spellings are C and C++ standard and are used in most parts of the PostgreSQL sources. The upper case spellings are only used in some files/modules. So standardize on the standard spellings. The APIs for ICU, Perl, and Windows define their own TRUE and FALSE, so those are left as is when using those APIs. In code comments, we use the lower-case spelling for the C concepts and keep the upper-case spelling for the SQL concepts. Reviewed-by: Michael Paquier <michael.paquier@gmail.com>
* Refactor new file permission handlingPeter Eisentraut2017-09-23
| | | | | | | | | | | | | | | | | | | The file handling functions from fd.c were called with a diverse mix of notations for the file permissions when they were opening new files. Almost all files created by the server should have the same permissions set. So change the API so that e.g. OpenTransientFile() automatically uses the standard permissions set, and OpenTransientFilePerm() is a new function that takes an explicit permissions set for the few cases where it is needed. This also saves an unnecessary argument for call sites that are just opening an existing file. While we're reviewing these APIs, get rid of the FileName typedef and use the standard const char * for the file name and mode_t for the file mode. This makes these functions match other file handling functions and removes an unnecessary layer of mysteriousness. We can also get rid of a few casts that way. Author: David Steele <david@pgmasters.net>
* Phase 3 of pgindent updates.Tom Lane2017-06-21
| | | | | | | | | | | | | | | | | | | | | | | | | Don't move parenthesized lines to the left, even if that means they flow past the right margin. By default, BSD indent lines up statement continuation lines that are within parentheses so that they start just to the right of the preceding left parenthesis. However, traditionally, if that resulted in the continuation line extending to the right of the desired right margin, then indent would push it left just far enough to not overrun the margin, if it could do so without making the continuation line start to the left of the current statement indent. That makes for a weird mix of indentations unless one has been completely rigid about never violating the 80-column limit. This behavior has been pretty universally panned by Postgres developers. Hence, disable it with indent's new -lpl switch, so that parenthesized lines are always lined up with the preceding left paren. This patch is much less interesting than the first round of indent changes, but also bulkier, so I thought it best to separate the effects. Discussion: https://postgr.es/m/E1dAmxK-0006EE-1r@gemulon.postgresql.org Discussion: https://postgr.es/m/30527.1495162840@sss.pgh.pa.us
* Phase 2 of pgindent updates.Tom Lane2017-06-21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Change pg_bsd_indent to follow upstream rules for placement of comments to the right of code, and remove pgindent hack that caused comments following #endif to not obey the general rule. Commit e3860ffa4dd0dad0dd9eea4be9cc1412373a8c89 wasn't actually using the published version of pg_bsd_indent, but a hacked-up version that tried to minimize the amount of movement of comments to the right of code. The situation of interest is where such a comment has to be moved to the right of its default placement at column 33 because there's code there. BSD indent has always moved right in units of tab stops in such cases --- but in the previous incarnation, indent was working in 8-space tab stops, while now it knows we use 4-space tabs. So the net result is that in about half the cases, such comments are placed one tab stop left of before. This is better all around: it leaves more room on the line for comment text, and it means that in such cases the comment uniformly starts at the next 4-space tab stop after the code, rather than sometimes one and sometimes two tabs after. Also, ensure that comments following #endif are indented the same as comments following other preprocessor commands such as #else. That inconsistency turns out to have been self-inflicted damage from a poorly-thought-through post-indent "fixup" in pgindent. This patch is much less interesting than the first round of indent changes, but also bulkier, so I thought it best to separate the effects. Discussion: https://postgr.es/m/E1dAmxK-0006EE-1r@gemulon.postgresql.org Discussion: https://postgr.es/m/30527.1495162840@sss.pgh.pa.us
* Post-PG 10 beta1 pgindent runBruce Momjian2017-05-17
| | | | perltidy run not included.
* Fix new warnings from GCC 7Peter Eisentraut2017-04-17
| | | | | This addresses the new warning types -Wformat-truncation -Wformat-overflow that are part of -Wall, via -Wformat, in GCC 7.
* Fsync directory after creating or unlinking file.Teodor Sigaev2017-03-27
| | | | | | | | | If file was created/deleted just before powerloss it's possible that file system will miss that. To prevent it, call fsync() where creating/ unlinkg file is critical. Author: Michael Paquier Reviewed-by: Ashutosh Bapat, Takayuki Tsunakawa, me
* Create and use wait events for read, write, and fsync operations.Robert Haas2017-03-18
| | | | | | | | | | | | | Previous commits, notably 53be0b1add7064ca5db3cd884302dfc3268d884e and 6f3bd98ebfc008cbd676da777bb0b2376c4c4bfa, made it possible to see from pg_stat_activity when a backend was stuck waiting for another backend, but it's also fairly common for a backend to be stuck waiting for an I/O. Add wait events for those operations, too. Rushabh Lathia, with further hacking by me. Reviewed and tested by Michael Paquier, Amit Kapila, Rajkumar Raghuwanshi, and Rahila Syed. Discussion: http://postgr.es/m/CAGPqQf0LsYHXREPAZqYGVkDqHSyjf=KsD=k0GTVPAuzyThh-VQ@mail.gmail.com
* Fix sloppy handling of corner-case errors in fd.c.Tom Lane2017-02-21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Several places in fd.c had badly-thought-through handling of error returns from lseek() and close(). The fact that those would seldom fail on valid FDs is probably the reason we've not noticed this up to now; but if they did fail, we'd get quite confused. LruDelete and LruInsert actually just Assert'd that lseek never fails, which is pretty awful on its face. In LruDelete, we indeed can't throw an error, because that's likely to get called during error abort and so throwing an error would probably just lead to an infinite loop. But by the same token, throwing an error from the close() right after that was ill-advised, not to mention that it would've left the LRU state corrupted since we'd already unlinked the VFD from the list. I also noticed that really, most of the time, we should know the current seek position and it shouldn't be necessary to do an lseek here at all. As patched, if we don't have a seek position and an lseek attempt doesn't give us one, we'll close the file but then subsequent re-open attempts will fail (except in the somewhat-unlikely case that a FileSeek(SEEK_SET) call comes between and allows us to re-establish a known target seek position). This isn't great but it won't result in any state corruption. Meanwhile, having an Assert instead of an honest test in LruInsert is really dangerous: if that lseek failed, a subsequent read or write would read or write from the start of the file, not where the caller expected, leading to data corruption. In both LruDelete and FileClose, if close() fails, just LOG that and mark the VFD closed anyway. Possibly leaking an FD is preferable to getting into an infinite loop or corrupting the VFD list. Besides, as far as I can tell from the POSIX spec, it's unspecified whether or not the file has been closed, so treating it as still open could be the wrong thing anyhow. I also fixed a number of other places that were being sloppy about behaving correctly when the seekPos is unknown. Also, I changed FileSeek to return -1 with EINVAL for the cases where it detects a bad offset, rather than throwing a hard elog(ERROR). It seemed pretty inconsistent that some bad-offset cases would get a failure return while others got elog(ERROR). It was missing an offset validity check for the SEEK_CUR case on a closed file, too. Back-patch to all supported branches, since all this code is fundamentally identical in all of them. Discussion: https://postgr.es/m/2982.1487617365@sss.pgh.pa.us
* Update copyright via script for 2017Bruce Momjian2017-01-03
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* Rename "pg_xlog" directory to "pg_wal".Robert Haas2016-10-20
| | | | | | | | | | | | | | | | | | | | | "xlog" is not a particularly clear abbreviation for "write-ahead log", and it sometimes confuses users into believe that the contents of the "pg_xlog" directory are not critical data, leading to unpleasant consequences. So, rename the directory to "pg_wal". This patch modifies pg_upgrade and pg_basebackup to understand both the old and new directory layouts; the former is necessary given the purpose of the tool, while the latter merely avoids an unnecessary backward-compatibility break. We may wish to consider renaming other programs, switches, and functions which still use the old "xlog" naming to also refer to "wal". However, that's still under discussion, so let's do just this much for now. Discussion: CAB7nPqTeC-8+zux8_-4ZD46V7YPwooeFxgndfsq5Rg8ibLVm1A@mail.gmail.com Michael Paquier
* Widen amount-to-flush arguments of FileWriteback and callers.Tom Lane2016-04-13
| | | | | | It's silly to define these counts as narrower than they might someday need to be. Also, I believe that the BLCKSZ * nflush calculation in mdwriteback was capable of overflowing an int.
* Fix assorted portability issues with using msync() for data flushing.Tom Lane2016-04-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 428b1d6b29ca599c5700d4bc4f4ce4c5880369bf introduced the use of msync() for flushing dirty data from the kernel's file buffers. Several portability issues were overlooked, though: * Not all implementations of mmap() think that nbytes == 0 means "map the whole file". To fix, use lseek() to find out the true length. Fix callers of pg_flush_data to be aware that nbytes == 0 may result in trashing the file's seek position. * Not all implementations of mmap() will accept partial-page mmap requests. To fix, round down the length request to whatever sysconf() says the page size is. (I think this is OK from a portability standpoint, because sysconf() is required by SUS v2, and we aren't trying to compile this part on Windows anyway. Buildfarm should let us know if not.) * On 32-bit machines, the file size might exceed the available free address space, or even exceed what will fit in size_t. Check for the latter explicitly to avoid passing a false request size to mmap(). If mmap fails, silently fall through to the next implementation method, rather than bleating to the postmaster log and giving up. * mmap'ing directories fails on some platforms, and even if it works, msync'ing the directory is quite unlikely to help, as for that matter are the other flush implementations. In pre_sync_fname(), just skip flush attempts on directories. In passing, copy-edit the comments a bit. Stas Kelvich and myself
* Include portability/mem.h into fd.c for MAP_FAILED.Andres Freund2016-03-12
| | | | | | Buildfarm members gaur and pademelon are old enough not to know about MAP_FAILED; which is used in 428b1d6. Include portability/mem.h to fix; as already done in a bunch of other places.
* Allow to trigger kernel writeback after a configurable number of writes.Andres Freund2016-03-10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently writes to the main data files of postgres all go through the OS page cache. This means that some operating systems can end up collecting a large number of dirty buffers in their respective page caches. When these dirty buffers are flushed to storage rapidly, be it because of fsync(), timeouts, or dirty ratios, latency for other reads and writes can increase massively. This is the primary reason for regular massive stalls observed in real world scenarios and artificial benchmarks; on rotating disks stalls on the order of hundreds of seconds have been observed. On linux it is possible to control this by reducing the global dirty limits significantly, reducing the above problem. But global configuration is rather problematic because it'll affect other applications; also PostgreSQL itself doesn't always generally want this behavior, e.g. for temporary files it's undesirable. Several operating systems allow some control over the kernel page cache. Linux has sync_file_range(2), several posix systems have msync(2) and posix_fadvise(2). sync_file_range(2) is preferable because it requires no special setup, whereas msync() requires the to-be-flushed range to be mmap'ed. For the purpose of flushing dirty data posix_fadvise(2) is the worst alternative, as flushing dirty data is just a side-effect of POSIX_FADV_DONTNEED, which also removes the pages from the page cache. Thus the feature is enabled by default only on linux, but can be enabled on all systems that have any of the above APIs. While desirable and likely possible this patch does not contain an implementation for windows. With the infrastructure added, writes made via checkpointer, bgwriter and normal user backends can be flushed after a configurable number of writes. Each of these sources of writes controlled by a separate GUC, checkpointer_flush_after, bgwriter_flush_after and backend_flush_after respectively; they're separate because the number of flushes that are good are separate, and because the performance considerations of controlled flushing for each of these are different. A later patch will add checkpoint sorting - after that flushes from the ckeckpoint will almost always be desirable. Bgwriter flushes are most of the time going to be random, which are slow on lots of storage hardware. Flushing in backends works well if the storage and bgwriter can keep up, but if not it can have negative consequences. This patch is likely to have negative performance consequences without checkpoint sorting, but unfortunately so has sorting without flush control. Discussion: alpine.DEB.2.10.1506011320000.28433@sto Author: Fabien Coelho and Andres Freund
* Introduce durable_rename() and durable_link_or_rename().Andres Freund2016-03-09
| | | | | | | | | | | | | | | | | | | | | | | | | Renaming a file using rename(2) is not guaranteed to be durable in face of crashes; especially on filesystems like xfs and ext4 when mounted with data=writeback. To be certain that a rename() atomically replaces the previous file contents in the face of crashes and different filesystems, one has to fsync the old filename, rename the file, fsync the new filename, fsync the containing directory. This sequence is not generally adhered to currently; which exposes us to data loss risks. To avoid having to repeat this arduous sequence, introduce durable_rename(), which wraps all that. Also add durable_link_or_rename(). Several places use link() (with a fallback to rename()) to rename a file, trying to avoid replacing the target file out of paranoia. Some of those rename sequences need to be durable as well. There seems little reason extend several copies of the same logic, so centralize the link() callers. This commit does not yet make use of the new functions; they're used in a followup commit. Author: Michael Paquier, Andres Freund Discussion: 56583BDD.9060302@2ndquadrant.com Backpatch: All supported branches
* Add some functions to fd.c for the convenience of extensions.Robert Haas2016-03-08
| | | | | | | | For example, if you want to perform an ioctl() on a file descriptor opened through the fd.c routines, there's no way to do that without being able to get at the underlying fd. KaiGai Kohei
* Update copyright for 2016Bruce Momjian2016-01-02
| | | | Backpatch certain files through 9.1
* Remove special cases for ETXTBSY from new fsync'ing logic.Tom Lane2015-05-29
| | | | | | | | | | The argument that this is a sufficiently-expected case to be silently ignored seems pretty thin. Andres had brought it up back when we were still considering that most fsync failures should be hard errors, and it probably would be legit not to fail hard for ETXTBSY --- but the same is true for EROFS and other cases, which is why we gave up on hard failures. ETXTBSY is surely not a normal case, so logging the failure seems fine from here.
* Fix fsync-at-startup code to not treat errors as fatal.Tom Lane2015-05-28
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 2ce439f3379aed857517c8ce207485655000fc8e introduced a rather serious regression, namely that if its scan of the data directory came across any un-fsync-able files, it would fail and thereby prevent database startup. Worse yet, symlinks to such files also caused the problem, which meant that crash restart was guaranteed to fail on certain common installations such as older Debian. After discussion, we agreed that (1) failure to start is worse than any consequence of not fsync'ing is likely to be, therefore treat all errors in this code as nonfatal; (2) we should not chase symlinks other than those that are expected to exist, namely pg_xlog/ and tablespace links under pg_tblspc/. The latter restriction avoids possibly fsync'ing a much larger part of the filesystem than intended, if the user has left random symlinks hanging about in the data directory. This commit takes care of that and also does some code beautification, mainly moving the relevant code into fd.c, which seems a much better place for it than xlog.c, and making sure that the conditional compilation for the pre_sync_fname pass has something to do with whether pg_flush_data works. I also relocated the call site in xlog.c down a few lines; it seems a bit silly to be doing this before ValidateXLOGDirectoryStructure(). The similar logic in initdb.c ought to be made to match this, but that change is noncritical and will be dealt with separately. Back-patch to all active branches, like the prior commit. Abhijit Menon-Sen and Tom Lane