Horton

Re: File system performance and pg_xlog

Bruce Momjian <pgman@candle.pha.pa.us>

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From: Bruce Momjian <pgman@candle.pha.pa.us>
To: mlw <markw@mohawksoft.com>
Cc: Marko Kreen <marko@l-t.ee>, Hackers List <pgsql-hackers@postgresql.org>
Date: 2001-05-07T16:09:41Z
Lists: pgsql-hackers 
One big performance issue is that PostgreSQL 7.1 uses fdatasync if it is
available.  However, according to RedHat, 2.2 Linux kernels have
fdatasync, but it really just acts as fsync.  In 2.4 kernels, fdatasync
is really fdatasync, I think.

That is a major issue for people running performance tests.  For
example, XFS may be slow on 2.2 kernels but not 2.4 kernels.

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