From: Josh Berkus <josh@agliodbs.com>
Organization: Aglio Database Solutions
To: pgsql-performance@postgresql.org
Subject: Re: bad performance on Solaris 10
Date: Wed, 5 Apr 2006 21:32:16 -0700
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Cc: Chris Mair <list@1006.org>, markir@paradise.net.nz,
 llonergan@greenplum.com
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Chris,

> Remounting the fs where $PGDATA lives with "forcedirectio"
> (together with logging, that is default) did not help
> (if not harm...) performance.

Not all of PG.  JUST pg_xlog.  forcedirectio is only a good idea for the xlog.

> Quickly playing around with wal_buffers on Linux and Mac OS X
> I see it influences the performance of my test a bit, maybe in the
> 10-20% range (I'm really doing quick tests, nothing systematic),
> but nowhere near as spectacularly as on Solaris.
>
> I'm happy so far, but I find it very surprising that this single
> parameter has such an impact (only on) Solaris 10.

That *is* interesting.  I hadn't tested this previously specifically on 
Solaris.

-- 
Josh Berkus
Aglio Database Solutions
San Francisco