From 21c27af65fb21a36ff263bcd9e8e7cac0419984c Mon Sep 17 00:00:00 2001 From: Alvaro Herrera Date: Mon, 10 Sep 2007 17:58:45 +0000 Subject: [PATCH] Remove the vacuum_delay_point call in count_nondeletable_pages, because we hold an exclusive lock on the table at this point, which we want to release as soon as possible. This is called in the phase of lazy vacuum where we truncate the empty pages at the end of the table. An alternative solution would be to lower the vacuum delay settings before starting the truncating phase, but this doesn't work very well in autovacuum due to the autobalancing code (which can cause other processes to change our cost delay settings). This case could be considered in the balancing code, but it is simpler this way. --- src/backend/commands/vacuumlazy.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/src/backend/commands/vacuumlazy.c b/src/backend/commands/vacuumlazy.c index ecc0ee7807..25e0e071a9 100644 --- a/src/backend/commands/vacuumlazy.c +++ b/src/backend/commands/vacuumlazy.c @@ -36,7 +36,7 @@ * * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/commands/vacuumlazy.c,v 1.91 2007/09/05 18:10:47 tgl Exp $ + * $PostgreSQL: pgsql/src/backend/commands/vacuumlazy.c,v 1.92 2007/09/10 17:58:45 alvherre Exp $ * *------------------------------------------------------------------------- */ @@ -868,7 +868,11 @@ count_nondeletable_pages(Relation onerel, LVRelStats *vacrelstats) bool tupgone, hastup; - vacuum_delay_point(); + /* + * We don't insert a vacuum delay point here, because we have an + * exclusive lock on the table which we want to hold for as short + * a time as possible. + */ blkno--;