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 1D290D8DE1 for ; Sun, 25 Sep 2005 12:27:41 -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 53385-07 for ; Sun, 25 Sep 2005 15:27:35 +0000 (GMT) Received: from zproxy.gmail.com (zproxy.gmail.com [64.233.162.204]) by svr1.postgresql.org (Postfix) with ESMTP id 32914D7FDC for ; Sun, 25 Sep 2005 12:27:34 -0300 (ADT) Received: by zproxy.gmail.com with SMTP id 13so150928nzp for ; Sun, 25 Sep 2005 08:27:31 -0700 (PDT) DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=beta; d=gmail.com; h=received:message-id:date:from:reply-to:to:subject:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; b=twl7I9n0t3NgBfaY055r7E/DcvUOflQBQws5NLkabCjKuoSEcfSVMJjtu7cCN8bWtQxoRF3BWOv34HNFL6xn1k+TWhbYxZX+7Y/VIJtENntqUGEq3G14224vtvVE5hmav0VmJWguzTeo6Q384ryXRERFYedS+haijxIdh4Gx3Is= Received: by 10.54.49.69 with SMTP id w69mr1043052wrw; Sun, 25 Sep 2005 08:27:31 -0700 (PDT) Received: by 10.54.148.2 with HTTP; Sun, 25 Sep 2005 08:27:31 -0700 (PDT) Message-ID: Date: Sun, 25 Sep 2005 15:27:31 +0000 From: Mike Rylander Reply-To: Mike Rylander To: pgsql-perform Subject: Re: Advice on RAID card In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Content-Disposition: inline References: <43367937.40809@canaan.co.il> X-Virus-Scanned: by amavisd-new at hub.org X-Spam-Status: No, hits=0.089 required=5 tests=[AWL=0.065, RCVD_BY_IP=0.024] X-Spam-Level: X-Archive-Number: 200509/331 X-Sequence-Number: 14639 On 9/25/05, Dave Cramer wrote: > I would think software raid would be quite inappropriate considering > postgres when it is working is taking a fair amount of CPU as would > software RAID. Does anyone know if this is really the case ? > I attempted to get some extra speed out of my Compaq/HP SA6404 card by using software RAID1 across to hardware RAID10 sets. It didn't help, but there was no noticeable load or drop in performance because of it. Granted, this was on a 4-way Opteron, but, anecdotally speaking, the linux software RAID has surprisingly low overhead. My $0.02, hope it helps. -- Mike Rylander mrylander@gmail.com GPLS -- PINES Development Database Developer http://open-ils.org