diff options
Diffstat (limited to 'src/backend/commands/vacuumlazy.c')
| -rw-r--r-- | src/backend/commands/vacuumlazy.c | 20 |
1 files changed, 18 insertions, 2 deletions
diff --git a/src/backend/commands/vacuumlazy.c b/src/backend/commands/vacuumlazy.c index f4703ee0175..17c61484ed2 100644 --- a/src/backend/commands/vacuumlazy.c +++ b/src/backend/commands/vacuumlazy.c @@ -33,7 +33,7 @@ * * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/commands/vacuumlazy.c,v 1.61.2.7 2009/01/06 14:55:56 heikki Exp $ + * $PostgreSQL: pgsql/src/backend/commands/vacuumlazy.c,v 1.61.2.8 2009/11/10 18:01:11 alvherre Exp $ * *------------------------------------------------------------------------- */ @@ -134,8 +134,11 @@ static int vac_cmp_page_spaces(const void *left, const void *right); * * At entry, we have already established a transaction and opened * and locked the relation. + * + * The return value indicates whether this function has held off + * interrupts -- caller must RESUME_INTERRUPTS() after commit if true. */ -void +bool lazy_vacuum_rel(Relation onerel, VacuumStmt *vacstmt) { LVRelStats *vacrelstats; @@ -143,6 +146,7 @@ lazy_vacuum_rel(Relation onerel, VacuumStmt *vacstmt) int nindexes; bool hasindex; BlockNumber possibly_freeable; + bool heldoff = false; if (vacstmt->verbose) elevel = INFO; @@ -173,12 +177,22 @@ lazy_vacuum_rel(Relation onerel, VacuumStmt *vacstmt) * * Don't even think about it unless we have a shot at releasing a goodly * number of pages. Otherwise, the time taken isn't worth it. + * + * Note that after we've truncated the heap, it's too late to abort the + * transaction; doing so would lose the sinval messages needed to tell + * the other backends about the table being shrunk. We prevent interrupts + * in that case; caller is responsible for re-enabling them after + * committing the transaction. */ possibly_freeable = vacrelstats->rel_pages - vacrelstats->nonempty_pages; if (possibly_freeable > 0 && (possibly_freeable >= REL_TRUNCATE_MINIMUM || possibly_freeable >= vacrelstats->rel_pages / REL_TRUNCATE_FRACTION)) + { + HOLD_INTERRUPTS(); + heldoff = true; lazy_truncate_heap(onerel, vacrelstats); + } /* Update shared free space map with final free space info */ lazy_update_fsm(onerel, vacrelstats); @@ -192,6 +206,8 @@ lazy_vacuum_rel(Relation onerel, VacuumStmt *vacstmt) /* report results to the stats collector, too */ pgstat_report_vacuum(RelationGetRelid(onerel), onerel->rd_rel->relisshared, vacstmt->analyze, vacrelstats->rel_tuples); + + return heldoff; } |