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Date: Thu, 06 Nov 2008 13:02:55 -0600
From: "Kevin Grittner" <Kevin.Grittner@wicourts.gov>
To: <pgsql-performance@postgresql.org>
Subject: Re: Create and drop temp table in 8.3.4
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>>> "Kevin Grittner" <Kevin.Grittner@wicourts.gov> wrote: 
> If I find a particular tweak to the background writer or some such
is
> particularly beneficial, I'll post again.
 
It turns out that it was not the PostgreSQL version which was
primarily responsible for the performance difference.  We updated the
kernel at the same time we rolled out 8.3.4, and the new kernel
defaulted to using write barriers, while the old kernel didn't.  Since
we have a BBU RAID controller, we will add nobarrier to the fstab
entries.  This makes file creation and unlink each about 20 times
faster.
 
-Kevin