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Reset btpo_cycleid in nbtree VACUUM's REDO routine.

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Reset btpo_cycleid to 0 in btree_xlog_vacuum for consistency with
_bt_delitems_vacuum (the corresponding original execution code).  This
makes things neater.

There might be some performance benefit to being consistent like this.
When btvacuumpage doesn't call _bt_delitems_vacuum, it can still
proactively reset btpo_cycleid to 0 via a separate hint-like update
mechanism (it does so whenever it sees that it isn't already set to 0).
And so it's possible that being consistent about resetting btpo_cycleid
like this will save work later on, after standby promotion: subsequent
VACUUMs won't need to clear btpo_cycleid using the hint-like update
mechanism as often as they otherwise would.

Author: Peter Geoghegan <pg@bowt.ie>
Reviewed-By: Andrey Borodin <x4mmm@yandex-team.ru>
Discussion: https://postgr.es/m/CAH2-Wz=+LDFxn9NZyEsCo8ifcyKt6+n-VLyygySEHgMz+oynqw@mail.gmail.com
This commit is contained in:
Peter Geoghegan 2024-12-23 15:46:00 -05:00
parent c431986de1
commit da9517fb3a
1 changed files with 7 additions and 3 deletions
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10
src/backend/access/nbtree/nbtxlog.c
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@ -634,10 +634,11 @@ btree_xlog_vacuum(XLogReaderState *record)
PageIndexMultiDelete(page, (OffsetNumber *) ptr, xlrec->ndeleted);
/*
* Mark the page as not containing any LP_DEAD items --- see comments
* in _bt_delitems_vacuum().
* Clear the vacuum cycle ID, and mark the page as not containing any
* LP_DEAD items
*/
opaque = BTPageGetOpaque(page);
opaque->btpo_cycleid = 0;
opaque->btpo_flags &= ~BTP_HAS_GARBAGE;
PageSetLSN(page, lsn);
@ -698,7 +699,10 @@ btree_xlog_delete(XLogReaderState *record)
if (xlrec->ndeleted > 0)
PageIndexMultiDelete(page, (OffsetNumber *) ptr, xlrec->ndeleted);
/* Mark the page as not containing any LP_DEAD items */
/*
* Do *not* clear the vacuum cycle ID, but do mark the page as not
* containing any LP_DEAD items
*/
opaque = BTPageGetOpaque(page);
opaque->btpo_flags &= ~BTP_HAS_GARBAGE;