From: Hannes Dorbath <light@theendofthetunnel.de>
To: pgsql-performance@postgresql.org
Subject: 8.3 synchronous_commit
Date: Mon, 21 Jan 2008 22:55:16 +0100
Message-ID: <fn34ca$2ff8$1@news.hub.org> (raw)
I might completely misunderstand this feature. Shouldn't
"synchronous_commit = off" improve performance?
Whatever I do, I find "synchronous_commit = off" to degrade performance.
Especially it doesn't like the CFQ I/O scheduler, it's not so bad with
deadline. Synthetic load like
pgbench -i -s 10 -U pgsql -d bench && pgbench -t 1000 -c 100 -U pgsql -d
bench
or the same with scale 100.
Maybe it's just my test box.. single SATA-II drive, XFS on top of LVM.
I'll retry without LVM once I have another drive.. I've seen LVM mess
with other things in the past.
--
Best regards,
Hannes Dorbath
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To: pgsql-performance@postgresql.org
Cc: light@theendofthetunnel.de
Subject: Re: 8.3 synchronous_commit
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