X-Original-To: pgsql-performance-postgresql.org@localhost.postgresql.org Received: from localhost (unknown [200.46.204.144]) by svr1.postgresql.org (Postfix) with ESMTP id B98DB52854 for ; Sat, 18 Jun 2005 13:00:27 -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 89224-08 for ; Sat, 18 Jun 2005 16:00:18 +0000 (GMT) Received: from boutiquenumerique.com (boutiquenumerique.com [82.67.9.10]) by svr1.postgresql.org (Postfix) with ESMTP id 632F35280D for ; Sat, 18 Jun 2005 13:00:17 -0300 (ADT) Received: (qmail 9186 invoked from network); 18 Jun 2005 18:00:29 +0200 Received: from unknown (HELO localhost) (boutiquenumerique-lists@192.168.0.4) by boutiquenumerique.com with SMTP; 18 Jun 2005 18:00:29 +0200 To: mudfoot@rawbw.com, pgsql-performance@postgresql.org Subject: Re: Multiple disks: RAID 5 or PG Cluster References: <7a1914222f313b7c5e88bedb8a662f12@implements.be> <1119040721.42b334d1c3ec9@webmail.rawbw.com> Message-ID: Date: Sat, 18 Jun 2005 18:00:14 +0200 From: PFC Organization: =?iso-8859-15?Q?La_Boutique_Num=E9rique?= Content-Type: text/plain; format=flowed; delsp=yes; charset=iso-8859-15 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit In-Reply-To: <1119040721.42b334d1c3ec9@webmail.rawbw.com> User-Agent: Opera M2(BETA2)/8.0 (Linux, build 987) X-Virus-Scanned: by amavisd-new at hub.org X-Spam-Status: No, hits=0.005 tagged_above=0 required=5 tests=AWL X-Spam-Level: X-Archive-Number: 200506/356 X-Sequence-Number: 12993 > I do not know what clustering would do for you. But striping will > provide a > high level of assurance that each of your hard drives will process > equivalent > amounts of IO operations. I don't know what I'm talking about, but wouldn't mirorring be faster than striping for random reads like you often get on a database ? (ie. the reads can be dispatched to any disk) ? (or course, not for writes, but if you won't use fsync, random writes should be reduced no ?)