From 2e92b5872faeb01f1865bb00556ec7be0ef006ee Mon Sep 17 00:00:00 2001 From: Heikki Linnakangas Date: Fri, 27 Jan 2012 09:09:50 +0200 Subject: [PATCH] Mention in the docs that bgwriter now sleeps longer when it has no work to do. --- doc/src/sgml/config.sgml | 14 ++++++++------ 1 file changed, 8 insertions(+), 6 deletions(-) diff --git a/doc/src/sgml/config.sgml b/doc/src/sgml/config.sgml index 309b6a5461..3a84321760 100644 --- a/doc/src/sgml/config.sgml +++ b/doc/src/sgml/config.sgml @@ -1322,12 +1322,14 @@ SET ENABLE_SEQSCAN TO OFF; background writer. In each round the writer issues writes for some number of dirty buffers (controllable by the following parameters). It then sleeps for bgwriter_delay - milliseconds, and repeats. The default value is 200 milliseconds - (200ms). Note that on many systems, the effective - resolution of sleep delays is 10 milliseconds; setting - bgwriter_delay to a value that is not a multiple of - 10 might have the same results as setting it to the next higher - multiple of 10. This parameter can only be set in the + milliseconds, and repeats. When there are no dirty buffers in the + buffer pool, though, it goes into a longer sleep regardless of + bgwriter_delay. The default value is 200 + milliseconds (200ms). Note that on many systems, the + effective resolution of sleep delays is 10 milliseconds; setting + bgwriter_delay to a value that is not a multiple of 10 + might have the same results as setting it to the next higher multiple + of 10. This parameter can only be set in the postgresql.conf file or on the server command line.