From: Gaetano Mendola <mendola@gmail.com>
Subject: Re: shared_buffers performance
Date: Tue, 15 Apr 2008 11:05:12 +0200
Organization: Hub.Org Networking Services
Lines: 24
Message-ID: <48046FC8.9030601@gmail.com>
References: <48032021.90704@gmail.com>
	<Pine.GSO.4.64.0804141132580.3587@westnet.com>
Mime-Version: 1.0
Content-Type: text/plain; charset=ISO-8859-1
Content-Transfer-Encoding: 7bit
To: Greg Smith <gsmith@gregsmith.com>
User-Agent: Thunderbird 2.0.0.12 (X11/20080227)
In-Reply-To: <Pine.GSO.4.64.0804141132580.3587@westnet.com>
To: pgsql-performance@postgresql.org

Greg Smith wrote:
> On Mon, 14 Apr 2008, Gaetano Mendola wrote:
> 
>> I'm using postgres 8.2.3 on Red Hat compiled with GCC 3.4.6.
> 
> 8.2.3 has a performance bug that impacts how accurate pgbench results
> are; you really should be using a later version.
> 
>> http://img84.imageshack.us/my.php?image=totalid7.png
>> as you can see using 64MB as value for shared_buffers I'm obtaining
>> better results.
> 
> I'm assuming you've read my scaling article at
> http://www.westnet.com/~gsmith/content/postgresql/pgbench-scaling.htm
> since you're using the graph template I suggest there.
> 

Yes I was basically inspired from that page, my true goal is not to study
the effect of shared_buffers (this was a side effect) but to study the
performance lose using DRBD on our server. I'm producing similar graph
using pgperf without -S, I will post them as soon they are ready.

Regards
Gaetano Mendola