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| author | Heikki Linnakangas <heikki.linnakangas@iki.fi> | 2009-01-06 14:56:13 +0000 |
|---|---|---|
| committer | Heikki Linnakangas <heikki.linnakangas@iki.fi> | 2009-01-06 14:56:13 +0000 |
| commit | 4d79a504942d7e3f58133bc56087137091f3a5b7 (patch) | |
| tree | dbee2ea974aac96a8bc3009547ebe134c3325567 /src/backend | |
| parent | 31f6cfb69077979f78fe854730c5d6e20f15a67a (diff) | |
| download | postgresql-4d79a504942d7e3f58133bc56087137091f3a5b7.tar.gz postgresql-4d79a504942d7e3f58133bc56087137091f3a5b7.zip | |
Fix logic in lazy vacuum to decide if it's worth trying to truncate the heap.
If the table was smaller than REL_TRUNCATE_FRACTION (= 16) pages, we always
tried to acquire AccessExclusiveLock on it even if there was no empty pages
at the end.
Report by Simon Riggs. Back-patch all the way to 7.4.
Diffstat (limited to 'src/backend')
| -rw-r--r-- | src/backend/commands/vacuumlazy.c | 7 |
1 files changed, 4 insertions, 3 deletions
diff --git a/src/backend/commands/vacuumlazy.c b/src/backend/commands/vacuumlazy.c index 732c6d4bf9f..d7daf1ba3c9 100644 --- a/src/backend/commands/vacuumlazy.c +++ b/src/backend/commands/vacuumlazy.c @@ -31,7 +31,7 @@ * * * IDENTIFICATION - * $Header: /cvsroot/pgsql/src/backend/commands/vacuumlazy.c,v 1.32.2.2 2007/09/16 02:38:25 tgl Exp $ + * $Header: /cvsroot/pgsql/src/backend/commands/vacuumlazy.c,v 1.32.2.3 2009/01/06 14:56:13 heikki Exp $ * *------------------------------------------------------------------------- */ @@ -161,8 +161,9 @@ lazy_vacuum_rel(Relation onerel, VacuumStmt *vacstmt) * number of pages. Otherwise, the time taken isn't worth it. */ possibly_freeable = vacrelstats->rel_pages - vacrelstats->nonempty_pages; - if (possibly_freeable >= REL_TRUNCATE_MINIMUM || - possibly_freeable >= vacrelstats->rel_pages / REL_TRUNCATE_FRACTION) + if (possibly_freeable > 0 && + (possibly_freeable >= REL_TRUNCATE_MINIMUM || + possibly_freeable >= vacrelstats->rel_pages / REL_TRUNCATE_FRACTION)) lazy_truncate_heap(onerel, vacrelstats); /* Update shared free space map with final free space info */ |