X-Original-To: pgsql-performance-postgresql.org@localhost.postgresql.org Received: from localhost (av.hub.org [200.46.204.144]) by svr1.postgresql.org (Postfix) with ESMTP id 514A1D8420 for ; Tue, 30 Aug 2005 10:50:32 -0300 (ADT) Received: from svr1.postgresql.org ([200.46.204.71]) by localhost (av.hub.org [200.46.204.144]) (amavisd-new, port 10024) with ESMTP id 65939-02 for ; Tue, 30 Aug 2005 13:50:31 +0000 (GMT) Received: from wolff.to (wolff.to [66.93.197.194]) by svr1.postgresql.org (Postfix) with SMTP id 3FEDED845E for ; Tue, 30 Aug 2005 10:50:29 -0300 (ADT) Received: (qmail 29287 invoked by uid 500); 30 Aug 2005 13:50:18 -0000 Date: Tue, 30 Aug 2005 08:50:18 -0500 From: Bruno Wolff III To: Alvaro Nunes Melo Cc: pgsql-performance@postgresql.org Subject: Re: RAID Configuration Sugestion Message-ID: <20050830135018.GA27789@wolff.to> Mail-Followup-To: Bruno Wolff III , Alvaro Nunes Melo , pgsql-performance@postgresql.org References: <431452FD.3090402@atua.com.br> <20050830125808.GD22545@wolff.to> <43145BE1.9050306@atua.com.br> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <43145BE1.9050306@atua.com.br> User-Agent: Mutt/1.5.6i X-Virus-Scanned: by amavisd-new at hub.org X-Spam-Status: No, hits=0.006 required=5 tests=[AWL=0.006] X-Spam-Level: X-Archive-Number: 200508/515 X-Sequence-Number: 14262 Please keep replies copied to the list so that others may contribute to and learn from the discussion. On Tue, Aug 30, 2005 at 10:15:13 -0300, Alvaro Nunes Melo wrote: > Hello Bruno, > > Bruno Wolff III wrote: > > >On Tue, Aug 30, 2005 at 09:37:17 -0300, > > Alvaro Nunes Melo wrote: > > > > > >>The server is a Dual Xeon 3.0 with 2 GB RAM and two SCSI disks. Our main > >>doubt is what is the best configuration for the disks. We are thinking > >>about use them in a RAID-0 array. Is this the best option? What do you > >>suggest on partitioning? Separate partitions for the OS, data and pg_xlog? > > > Our main goal is performance speedup. Disk space might not be a problem. > I've read a lot here about movig pg_xlog to different partitions, and > we'll surely make tests to see what configuration might be better. This isn't a very good mix of hardware for running postgres. Xeons have some context switching issues for which you will probably see some speed up in 8.1. (So if you aren't going into production for sevral months you might want to be using 8.1beta.) Having only two disk drives is also not a good idea. With what you have you either want to use raid 0 and not worry too much about how the disks are partitioned or use one disk for wal logging and the other for other stuff. There are other people on the list who can probably give you a better idea of which of these options is likely to be better in your case. However, they may need to know more about your raid controller. In particular how much battery backed memory does it have and its model.