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2025-10-09Eliminate COPY FREEZE use of XLOG_HEAP2_VISIBLEMelanie Plageman
Instead of emitting a separate WAL XLOG_HEAP2_VISIBLE record for setting bits in the VM, specify the VM block changes in the XLOG_HEAP2_MULTI_INSERT record. This halves the number of WAL records emitted by COPY FREEZE. Author: Melanie Plageman <[email protected]> Reviewed-by: Andres Freund <[email protected]> Reviewed-by: Robert Haas <[email protected]> Reviewed-by: Kirill Reshke <[email protected]> Discussion: https://postgr.es/m/flat/CAAKRu_ZMw6Npd_qm2KM%2BFwQ3cMOMx1Dh3VMhp8-V7SOLxdK9-g%40mail.gmail.com
2025-01-01Update copyright for 2025Bruce Momjian
Backpatch-through: 13
2024-12-17Make visibilitymap_set() return previous state of vmbitsMelanie Plageman
It can be useful to know the state of a relation page's VM bits before visibilitymap_set(). visibilitymap_set() has the old value on hand, so returning it is simple. This commit does not use visibilitymap_set()'s new return value. Author: Melanie Plageman Reviewed-by: Masahiko Sawada, Andres Freund, Nitin Jadhav, Bilal Yavuz Discussion: https://postgr.es/m/flat/CAAKRu_ZQe26xdvAqo4weHLR%3DivQ8J4xrSfDDD8uXnh-O-6P6Lg%40mail.gmail.com#6d8d2b4219394f774889509bf3bdc13d, https://postgr.es/m/ctdjzroezaxmiyah3gwbwm67defsrwj2b5fpfs4ku6msfpxeia%40mwjyqlhwr2wu
2024-01-04Update copyright for 2024Bruce Momjian
Reported-by: Michael Paquier Discussion: https://postgr.es/m/[email protected] Backpatch-through: 12
2023-01-02Update copyright for 2023Bruce Momjian
Backpatch-through: 11
2022-01-08Update copyright for 2022Bruce Momjian
Backpatch-through: 10
2021-09-23Split macros from visibilitymap.h into a separate headerAlexander Korotkov
That allows to include just visibilitymapdefs.h from file.c, and in turn, remove include of postgres.h from relcache.h. Reported-by: Andres Freund Discussion: https://postgr.es/m/20210913232614.czafiubr435l6egi%40alap3.anarazel.de Author: Alexander Korotkov Reviewed-by: Andres Freund, Tom Lane, Alvaro Herrera Backpatch-through: 13
2021-01-02Update copyright for 2021Bruce Momjian
Backpatch-through: 9.5
2020-05-14Initial pgindent and pgperltidy run for v13.Tom Lane
Includes some manual cleanup of places that pgindent messed up, most of which weren't per project style anyway. Notably, it seems some people didn't absorb the style rules of commit c9d297751, because there were a bunch of new occurrences of function calls with a newline just after the left paren, all with faulty expectations about how the rest of the call would get indented.
2020-01-01Update copyrights for 2020Bruce Momjian
Backpatch-through: update all files in master, backpatch legal files through 9.4
2019-09-24Speedup truncations of relation forks.Fujii Masao
When a relation is truncated, shared_buffers needs to be scanned so that any buffers for the relation forks are invalidated in it. Previously, shared_buffers was scanned for each relation forks, i.e., MAIN, FSM and VM, when VACUUM truncated off any empty pages at the end of relation or TRUNCATE truncated the relation in place. Since shared_buffers needed to be scanned multiple times, it could take a long time to finish those commands especially when shared_buffers was large. This commit changes the logic so that shared_buffers is scanned only one time for those three relation forks. Author: Kirk Jamison Reviewed-by: Masahiko Sawada, Thomas Munro, Alvaro Herrera, Takayuki Tsunakawa and Fujii Masao Discussion: https://postgr.es/m/D09B13F772D2274BB348A310EE3027C64E2067@g01jpexmbkw24
2019-05-22Phase 2 pgindent run for v12.Tom Lane
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
2019-01-02Update copyright for 2019Bruce Momjian
Backpatch-through: certain files through 9.4
2018-01-03Update copyright for 2018Bruce Momjian
Backpatch-through: certain files through 9.3
2017-06-21Phase 2 of pgindent updates.Tom Lane
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/[email protected] Discussion: https://postgr.es/m/[email protected]
2017-02-06Fix typos in comments.Heikki Linnakangas
Backpatch to all supported versions, where applicable, to make backpatching of future fixes go more smoothly. Josh Soref Discussion: https://www.postgresql.org/message-id/CACZqfqCf+5qRztLPgmmosr-B0Ye4srWzzw_mo4c_8_B_mtjmJQ@mail.gmail.com
2017-01-03Update copyright via script for 2017Bruce Momjian
2016-07-18Clear all-frozen visibilitymap status when locking tuples.Andres Freund
Since a892234 & fd31cd265 the visibilitymap's freeze bit is used to avoid vacuuming the whole relation in anti-wraparound vacuums. Doing so correctly relies on not adding xids to the heap without also unsetting the visibilitymap flag. Tuple locking related code has not done so. To allow selectively resetting all-frozen - to avoid pessimizing heap_lock_tuple - allow to selectively reset the all-frozen with visibilitymap_clear(). To avoid having to use visibilitymap_get_status (e.g. via VM_ALL_FROZEN) inside a critical section, have visibilitymap_clear() return whether any bits have been reset. There's a remaining issue (denoted by XXX): After the PageIsAllVisible() check in heap_lock_tuple() and heap_lock_updated_tuple_rec() the page status could theoretically change. Practically that currently seems impossible, because updaters will hold a page level pin already. Due to the next beta coming up, it seems better to get the required WAL magic bump done before resolving this issue. The added flags field fields to xl_heap_lock and xl_heap_lock_updated require bumping the WAL magic. Since there's already been a catversion bump since the last beta, that's not an issue. Reviewed-By: Robert Haas, Amit Kapila and Andres Freund Author: Masahiko Sawada, heavily revised by Andres Freund Discussion: CAEepm=3fWAbWryVW9swHyLTY4sXVf0xbLvXqOwUoDiNCx9mBjQ@mail.gmail.com Backpatch: -
2016-06-09pgindent run for 9.6Robert Haas
2016-06-03Cosmetic improvements to freeze map code.Robert Haas
Per post-commit review comments from Andres Freund, improve variable names, comments, and in one place, slightly improve the code structure. Masahiko Sawada
2016-03-02Change the format of the VM fork to add a second bit per page.Robert Haas
The new bit indicates whether every tuple on the page is already frozen. It is cleared only when the all-visible bit is cleared, and it can be set only when we vacuum a page and find that every tuple on that page is both visible to every transaction and in no need of any future vacuuming. A future commit will use this new bit to optimize away full-table scans that would otherwise be triggered by XID wraparound considerations. A page which is merely all-visible must still be scanned in that case, but a page which is all-frozen need not be. This commit does not attempt that optimization, although that optimization is the goal here. It seems better to get the basic infrastructure in place first. Per discussion, it's very desirable for pg_upgrade to automatically migrate existing VM forks from the old format to the new format. That, too, will be handled in a follow-on patch. Masahiko Sawada, reviewed by Kyotaro Horiguchi, Fujii Masao, Amit Kapila, Simon Riggs, Andres Freund, and others, and substantially revised by me.
2016-01-02Update copyright for 2016Bruce Momjian
Backpatch certain files through 9.1
2015-01-06Update copyright for 2015Bruce Momjian
Backpatch certain files through 9.0
2014-01-07Update copyright for 2014Bruce Momjian
Update all files in head, and files COPYRIGHT and legal.sgml in all back branches.
2013-03-22Allow I/O reliability checks using 16-bit checksumsSimon Riggs
Checksums are set immediately prior to flush out of shared buffers and checked when pages are read in again. Hint bit setting will require full page write when block is dirtied, which causes various infrastructure changes. Extensive comments, docs and README. WARNING message thrown if checksum fails on non-all zeroes page; ERROR thrown but can be disabled with ignore_checksum_failure = on. Feature enabled by an initdb option, since transition from option off to option on is long and complex and has not yet been implemented. Default is not to use checksums. Checksum used is WAL CRC-32 truncated to 16-bits. Simon Riggs, Jeff Davis, Greg Smith Wide input and assistance from many community members. Thank you.
2013-01-01Update copyrights for 2013Bruce Momjian
Fully update git head, and update back branches in ./COPYRIGHT and legal.sgml files.
2012-04-27Prevent index-only scans from returning wrong answers under Hot Standby.Robert Haas
The alternative of disallowing index-only scans in HS operation was discussed, but the consensus was that it was better to treat marking a page all-visible as a recovery conflict for snapshots that could still fail to see XIDs on that page. We may in the future try to soften this, so that we simply force index scans to do heap fetches in cases where this may be an issue, rather than throwing a hard conflict.
2012-01-01Update copyright notices for year 2012.Bruce Momjian
2011-10-14Measure the number of all-visible pages for use in index-only scan costing.Tom Lane
Add a column pg_class.relallvisible to remember the number of pages that were all-visible according to the visibility map as of the last VACUUM (or ANALYZE, or some other operations that update pg_class.relpages). Use relallvisible/relpages, instead of an arbitrary constant, to estimate how many heap page fetches can be avoided during an index-only scan. This is pretty primitive and will no doubt see refinements once we've acquired more field experience with the index-only scan mechanism, but it's way better than using a constant. Note: I had to adjust an underspecified query in the window.sql regression test, because it was changing answers when the plan changed to use an index-only scan. Some of the adjacent tests perhaps should be adjusted as well, but I didn't do that here.
2011-06-22Make the visibility map crash-safe.Robert Haas
This involves two main changes from the previous behavior. First, when we set a bit in the visibility map, emit a new WAL record of type XLOG_HEAP2_VISIBLE. Replay sets the page-level PD_ALL_VISIBLE bit and the visibility map bit. Second, when inserting, updating, or deleting a tuple, we can no longer get away with clearing the visibility map bit after releasing the lock on the corresponding heap page, because an intervening crash might leave the visibility map bit set and the page-level bit clear. Making this work requires a bit of interface refactoring. In passing, a few minor but related cleanups: change the test in visibilitymap_set and visibilitymap_clear to throw an error if the wrong page (or no page) is pinned, rather than silently doing nothing; this case should never occur. Also, remove duplicate definitions of InvalidXLogRecPtr. Patch by me, review by Noah Misch.
2011-01-01Stamp copyrights for year 2011.Bruce Momjian
2010-09-20Remove cvs keywords from all files.Magnus Hagander
2010-01-02Update copyright for the year 2010.Bruce Momjian
2009-08-24Fix a violation of WAL coding rules in the recent patch to include anTom Lane
"all tuples visible" flag in heap page headers. The flag update *must* be applied before calling XLogInsert, but heap_update and the tuple moving routines in VACUUM FULL were ignoring this rule. A crash and replay could therefore leave the flag incorrectly set, causing rows to appear visible in seqscans when they should not be. This might explain recent reports of data corruption from Jeff Ross and others. In passing, do a bit of editorialization on comments in visibilitymap.c.
2009-06-118.4 pgindent run, with new combined Linux/FreeBSD/MinGW typedef listBruce Momjian
provided by Andrew.
2009-01-01Update copyright for 2009.Bruce Momjian
2008-12-12Reduce some rel.h inclusions, and add pg_list.h to pg_proc_fn.h.Alvaro Herrera
2008-12-03Introduce visibility map. The visibility map is a bitmap with one bit perHeikki Linnakangas
heap page, where a set bit indicates that all tuples on the page are visible to all transactions, and the page therefore doesn't need vacuuming. It is stored in a new relation fork. Lazy vacuum uses the visibility map to skip pages that don't need vacuuming. Vacuum is also responsible for setting the bits in the map. In the future, this can hopefully be used to implement index-only-scans, but we can't currently guarantee that the visibility map is always 100% up-to-date. In addition to the visibility map, there's a new PD_ALL_VISIBLE flag on each heap page, also indicating that all tuples on the page are visible to all transactions. It's important that this flag is kept up-to-date. It is also used to skip visibility tests in sequential scans, which gives a small performance gain on seqscans.