From 21c27af65fb21a36ff263bcd9e8e7cac0419984c Mon Sep 17 00:00:00 2001
From: Alvaro Herrera <alvherre@alvh.no-ip.org>
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 ecc0ee78074..25e0e071a93 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--;
 
-- 
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