Received: from maia.hub.org (maia-2.hub.org [200.46.204.251]) by mail.postgresql.org (Postfix) with ESMTP id 75FA1B5DBD6 for ; Wed, 17 Aug 2011 15:56:26 -0300 (ADT) Received: from mail.postgresql.org ([200.46.204.86]) by maia.hub.org (mx1.hub.org [200.46.204.251]) (amavisd-maia, port 10024) with ESMTP id 21870-04-2 for ; Wed, 17 Aug 2011 18:56:20 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from mxout-07.mxes.net (mxout-07.mxes.net [216.86.168.182]) by mail.postgresql.org (Postfix) with ESMTP id B2C5DB5DC0A for ; Wed, 17 Aug 2011 15:56:17 -0300 (ADT) Received: from [192.168.1.108] (unknown [173.165.13.38]) by smtp.mxes.net (Postfix) with ESMTPA id 838DD22E256; Wed, 17 Aug 2011 14:56:17 -0400 (EDT) Subject: Re: Raid 5 vs Raid 10 Benchmarks Using bonnie++ Mime-Version: 1.0 (Apple Message framework v1082) Content-Type: text/plain; charset=us-ascii From: Ogden In-Reply-To: <4E4C0969.5030401@gpdnet.co.uk> Date: Wed, 17 Aug 2011 13:56:17 -0500 Cc: pgsql-performance@postgresql.org Content-Transfer-Encoding: quoted-printable Message-Id: References: <959BD2FA-0312-458B-BD5F-ED358D2C47ED@darkstatic.com> <75A85649-2B95-43D5-8404-4776D2E580EC@darkstatic.com> <4E4C0969.5030401@gpdnet.co.uk> To: Gary Doades X-Mailer: Apple Mail (2.1082) X-Virus-Scanned: Maia Mailguard 1.0.1 X-Spam-Status: No, hits=-1.9 tagged_above=-10 required=5 tests=BAYES_00=-1.9 X-Spam-Level: X-Archive-Number: 201108/192 X-Sequence-Number: 44639 On Aug 17, 2011, at 1:33 PM, Gary Doades wrote: > On 17/08/2011 7:26 PM, Ogden wrote: >> I am using bonnie++ to benchmark our current Postgres system (on RAID = 5) with the new one we have, which I have configured with RAID 10. The = drives are the same (SAS 15K). I tried the new system with ext3 and then = XFS but the results seem really outrageous as compared to the current = system, or am I reading things wrong? >>=20 >> The benchmark results are here: >>=20 >> http://malekkoheavyindustry.com/benchmark.html >>=20 > The results are not completely outrageous, however you don't say what = drives, how many and what RAID controller you have in the current and = new systems. You might expect that performance from 10/12 disks in RAID = 10 with a good controller. I would say that your current system is = outrageous in that is is so slow! >=20 > Cheers, > Gary. Yes, under heavy writes the load would shoot right up which is what = caused us to look at upgrading. If it is the RAID 5, it is mind boggling = that it could be that much of a difference. I expected a difference, now = that much.=20 The new system has 6 drives, 300Gb 15K SAS and I've put them into a RAID = 10 configuration. The current system is ext3 with RAID 5 over 4 disks on = a Perc/5i controller which has half the write cache as the new one (256 = Mb vs 512Mb).=20 Ogden=