Received: from makus.postgresql.org (makus.postgresql.org [98.129.198.125]) by mail.postgresql.org (Postfix) with ESMTP id 9C90C1648184 for ; Fri, 30 Mar 2012 12:03:12 -0300 (ADT) Received: from relay3-d.mail.gandi.net ([217.70.183.195]) by makus.postgresql.org with esmtp (Exim 4.72) (envelope-from ) id 1SDdM7-0002PA-9R for pgsql-performance@postgresql.org; Fri, 30 Mar 2012 15:03:12 +0000 X-Originating-IP: 217.70.178.146 Received: from mfilter18-d.gandi.net (mfilter18-d.gandi.net [217.70.178.146]) by relay3-d.mail.gandi.net (Postfix) with ESMTP id F1930A8070; Fri, 30 Mar 2012 17:02:47 +0200 (CEST) X-Virus-Scanned: Debian amavisd-new at mfilter18-d.gandi.net Received: from relay3-d.mail.gandi.net ([217.70.183.195]) by mfilter18-d.gandi.net (mfilter18-d.gandi.net [10.0.15.180]) (amavisd-new, port 10024) with ESMTP id 9aDDeET4WikP; Fri, 30 Mar 2012 17:02:46 +0200 (CEST) X-Originating-IP: 98.27.54.176 Received: from [192.168.10.146] (cpe-098-027-054-176.nc.res.rr.com [98.27.54.176]) (Authenticated sender: adsend@dunslane.net) by relay3-d.mail.gandi.net (Postfix) with ESMTPSA id 1BB54A807D; Fri, 30 Mar 2012 17:02:45 +0200 (CEST) Message-ID: <4F75CB14.9060607@dunslane.net> Date: Fri, 30 Mar 2012 11:02:44 -0400 From: Andrew Dunstan User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:10.0.1) Gecko/20120216 Thunderbird/10.0.1 MIME-Version: 1.0 To: "Campbell, Lance" CC: "pgsql-performance@postgresql.org" Subject: Re: Tablespaces on a raid configuration References: In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Pg-Spam-Score: -1.9 (-) X-Archive-Number: 201203/188 X-Sequence-Number: 46638 On 03/30/2012 10:45 AM, Campbell, Lance wrote: > > PostgreSQL 9.0.x > > When PostgreSQL storage is using a relatively large raid 5 or 6 > array is there any value in having your tables distributed across > multiple tablespaces if those tablespaces will exists on the same raid > array? I understand the value if you were to have the tablespaces on > different raid arrays. But what about on the same one? > > Not answering your question, but standard advice is not to use RAID 5 or 6, but RAID 10 for databases. Not sure if that still hold if you're using SSDs. cheers andrew