Subject: Re: Postgresql Performance on an HP DL385 and
From: Scott Marlowe <smarlowe@g2switchworks.com>
To: Luke Lonergan <llonergan@greenplum.com>
Cc: Michael Stone <mstone+postgres@mathom.us>,
 pgsql-performance@postgresql.org
In-Reply-To: <C1009BAA.2DE12%llonergan@greenplum.com>
References: <C1009BAA.2DE12%llonergan@greenplum.com>
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Date: Thu, 10 Aug 2006 10:35:10 -0500

On Thu, 2006-08-10 at 10:15, Luke Lonergan wrote:
> Mike,
> 
> On 8/10/06 4:09 AM, "Michael Stone" <mstone+postgres@mathom.us> wrote:
> 
> > On Wed, Aug 09, 2006 at 08:29:13PM -0700, Steve Poe wrote:
> >> I tried as you suggested and my performance dropped by 50%. I went from
> >> a 32 TPS to 16. Oh well.
> > 
> > If you put data & xlog on the same array, put them on seperate
> > partitions, probably formatted differently (ext2 on xlog).
> 
> If he's doing the same thing on both systems (Sun and HP) and the HP
> performance is dramatically worse despite using more disks and having faster
> CPUs and more RAM, ISTM the problem isn't the configuration.
> 
> Add to this the fact that the Sun machine is CPU bound while the HP is I/O
> wait bound and I think the problem is the disk hardware or the driver
> therein.

I agree.  The problem here looks to be the RAID controller.

Steve, got access to a different RAID controller to test with?