Peter Geoghegan 8523492d4e Remove tupgone special case from vacuumlazy.c. ... Retry the call to heap_prune_page() in rare cases where there is disagreement between the heap_prune_page() call and the call to HeapTupleSatisfiesVacuum() that immediately follows. Disagreement is possible when a concurrently-aborted transaction makes a tuple DEAD during the tiny window between each step. This was the only case where a tuple considered DEAD by VACUUM still had storage following pruning. VACUUM's definition of dead tuples is now uniformly simple and unambiguous: dead tuples from each page are always LP_DEAD line pointers that were encountered just after we performed pruning (and just before we considered freezing remaining items with tuple storage). Eliminating the tupgone=true special case enables INDEX_CLEANUP=off style skipping of index vacuuming that takes place based on flexible, dynamic criteria. The INDEX_CLEANUP=off case had to know about skipping indexes up-front before now, due to a subtle interaction with the special case (see commit dd695979) -- this was a special case unto itself. Now there are no special cases. And so now it won't matter when or how we decide to skip index vacuuming: it won't affect how pruning behaves, and it won't be affected by any of the implementation details of pruning or freezing. Also remove XLOG_HEAP2_CLEANUP_INFO records. These are no longer necessary because we now rely entirely on heap pruning taking care of recovery conflicts. There is no longer any need to generate recovery conflicts for DEAD tuples that pruning just missed. This also means that heap vacuuming now uses exactly the same strategy for recovery conflicts as index vacuuming always has: REDO routines never need to process a latestRemovedXid from the WAL record, since earlier REDO of the WAL record from pruning is sufficient in all cases. The generic XLOG_HEAP2_CLEAN record type is now split into two new record types to reflect this new division (these are called XLOG_HEAP2_PRUNE and XLOG_HEAP2_VACUUM). Also stop acquiring a super-exclusive lock for heap pages when they're vacuumed during VACUUM's second heap pass. A regular exclusive lock is enough. This is correct because heap page vacuuming is now strictly a matter of setting the LP_DEAD line pointers to LP_UNUSED. No other backend can have a pointer to a tuple located in a pinned buffer that can be invalidated by a concurrent heap page vacuum operation. Heap vacuuming can now be thought of as conceptually similar to index vacuuming and conceptually dissimilar to heap pruning. Heap pruning now has sole responsibility for anything involving the logical contents of the database (e.g., managing transaction status information, recovery conflicts, considering what to do with HOT chains). Index vacuuming and heap vacuuming are now only concerned with recycling garbage items from physical data structures that back the logical database. Bump XLOG_PAGE_MAGIC due to pruning and heap page vacuum WAL record changes. Credit for the idea of retrying pruning a page to avoid the tupgone case goes to Andres Freund. Author: Peter Geoghegan <pg@bowt.ie> Reviewed-By: Andres Freund <andres@anarazel.de> Reviewed-By: Masahiko Sawada <sawada.mshk@gmail.com> Discussion: https://postgr.es/m/CAH2-WznneCXTzuFmcwx_EyRQgfsfJAAsu+CsqRFmFXCAar=nJw@mail.gmail.com		2021-04-06 08:49:22 -07:00
..
backend	Remove tupgone special case from vacuumlazy.c.	2021-04-06 08:49:22 -07:00
bin	psql: Show all query results by default	2021-04-06 17:10:24 +02:00
common	Refactor HMAC implementations	2021-04-03 17:30:49 +09:00
fe_utils	psql: call clearerr() just before printing	2021-03-29 18:34:39 -03:00
include	Remove tupgone special case from vacuumlazy.c.	2021-04-06 08:49:22 -07:00
interfaces	Fix compiler warning in fe-trace.c for MSVC	2021-04-06 18:33:40 +12:00
makefiles	Remove libpq.rc, use win32ver.rc for libpq	2020-01-15 15:06:12 +01:00
pl	Remove extra increment of plpgsql's statement counter for FOR loops.	2021-02-02 14:35:12 -05:00
port	Move bsearch_arg to src/port	2021-03-23 00:11:22 +01:00
template	Further tweaking of PG_SYSROOT heuristics for macOS.	2021-01-20 12:07:23 -05:00
test	psql: Show all query results by default	2021-04-06 17:10:24 +02:00
timezone	Update time zone data files to tzdata release 2021a.	2021-01-24 16:29:47 -05:00
tools	Remove tupgone special case from vacuumlazy.c.	2021-04-06 08:49:22 -07:00
tutorial	tutorial: land height is "elevation", not "altitude"	2021-03-10 20:25:19 -05:00
.gitignore	Convert cvsignore to gitignore, and add .gitignore for build targets.	2010-09-22 12:57:04 +02:00
DEVELOPERS	Replace a couple of references to files that no longer exist in the source	2009-05-04 08:08:47 +00:00
Makefile	Remove the option to build thread_test.c outside configure.	2020-10-21 12:08:48 -04:00
Makefile.global.in	Introduce --with-ssl={openssl} as a configure option	2021-02-01 19:19:44 +09:00
Makefile.shlib	Add PostgreSQL home page to --help output	2020-02-28 13:12:21 +01:00
nls-global.mk	Add errhint_plural() function and make use of it	2021-03-31 09:16:25 +02:00