Date: Fri, 22 Sep 2006 09:02:29 -0500
From: "Jim C. Nasby" <jim@nasby.net>
To: Bruce Momjian <bruce@momjian.us>
Cc: Guy Thornley <guy@esphion.com>, Markus Schaber <schabi@logix-tt.com>,
	Luke Lonergan <llonergan@greenplum.com>, pgsql-performance@postgresql.org
Subject: Re: Large tables (was: RAID 0 not as fast as
Message-ID: <20060922140228.GX28987@nasby.net>
References: <20060922025209.GO6211@esphion.com>
	<200609220305.k8M35dI10346@momjian.us>
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On Thu, Sep 21, 2006 at 11:05:39PM -0400, Bruce Momjian wrote:
> We tried posix_fadvise() during the 8.2 development cycle, but had
> problems as outlined in a comment in xlog.c:
> 
>     /*
>      * posix_fadvise is problematic on many platforms: on older x86 Linux
>      * it just dumps core, and there are reports of problems on PPC platforms
>      * as well.  The following is therefore disabled for the time being.
>      * We could consider some kind of configure test to see if it's safe to
>      * use, but since we lack hard evidence that there's any useful performance
>      * gain to be had, spending time on that seems unprofitable for now.
>      */

In case it's not clear, that's a call for someone to do some performance
testing. :)

Bruce, you happen to have a URL for a patch to put fadvise in?
-- 
Jim Nasby                                            jim@nasby.net
EnterpriseDB      http://enterprisedb.com      512.569.9461 (cell)