Received: from localhost (maia-5.hub.org [200.46.204.182]) by postgresql.org (Postfix) with ESMTP id 6C6299FA1DE for ; Mon, 4 Dec 2006 14:05:22 -0400 (AST) Received: from postgresql.org ([200.46.204.71]) by localhost (mx1.hub.org [200.46.204.182]) (amavisd-new, port 10024) with ESMTP id 51728-09 for ; Mon, 4 Dec 2006 14:05:10 -0400 (AST) X-Greylist: from auto-whitelisted by SQLgrey-1.7.4 Received: from exchange.g2switchworks.com (mail.g2switchworks.com [63.87.162.25]) by postgresql.org (Postfix) with ESMTP id F11B49FA182 for ; Mon, 4 Dec 2006 14:05:10 -0400 (AST) Received: from 10.10.1.37 ([10.10.1.37]) by exchange.g2switchworks.com ([10.10.1.2]) with Microsoft Exchange Server HTTP-DAV ; Mon, 4 Dec 2006 18:05:08 +0000 Received: from state.g2switchworks.com by mail.g2switchworks.com; 04 Dec 2006 12:05:15 -0600 Subject: Re: Bad iostat numbers From: Scott Marlowe To: Michael Stone Cc: pgsql-performance@postgresql.org In-Reply-To: <20061204174320.GX1622@mathom.us> References: <33c6269f0612032317t9f0bc77n3ff791a5cd88fc80@mail.gmail.com> <1165249513.14565.329.camel@state.g2switchworks.com> <33c6269f0612040937l276c5178naecac1983d355e29@mail.gmail.com> <20061204174320.GX1622@mathom.us> Content-Type: text/plain Content-Transfer-Encoding: 7bit Message-Id: <1165255515.14565.337.camel@state.g2switchworks.com> Mime-Version: 1.0 X-Mailer: Ximian Evolution 1.4.6 (1.4.6-2) Date: Mon, 04 Dec 2006 12:05:15 -0600 X-Virus-Scanned: Maia Mailguard 1.0.1 X-Archive-Number: 200612/56 X-Sequence-Number: 22112 On Mon, 2006-12-04 at 11:43, Michael Stone wrote: > On Mon, Dec 04, 2006 at 12:37:29PM -0500, Alex Turner wrote: > >This discussion I think is important, as I think it would be useful for this > >list to have a list of RAID cards that _do_ work well under Linux/BSD for > >people as recommended hardware for Postgresql. So far, all I can recommend > >is what I've found to be good, which is 3ware 9500 series cards with 10k > >SATA drives. Throughput was great until you reached higher levels of RAID > >10 (the bonnie++ mark I posted showed write speed is a bit slow). But that > >doesn't solve the problem for SCSI. What cards in the SCSI arena solve the > >problem optimally? Why should we settle for sub-optimal performance in SCSI > >when there are a number of almost optimally performing cards in the SATA > >world (Areca, 3Ware/AMCC, LSI). > > Well, one factor is to be more precise about what you're looking for; a > HBA != RAID controller, and you may be comparing apples and oranges. (If > you have an external array with an onboard controller you probably want > a simple HBA rather than a RAID controller.) I think he's been pretty clear. He's just talking about SCSI based RAID controllers is all.