X-Original-To: pgsql-performance-postgresql.org@postgresql.org Received: from localhost (wm.hub.org [200.46.204.128]) by postgresql.org (Postfix) with ESMTP id 676089F94F3 for ; Mon, 17 Jul 2006 21:23:03 -0300 (ADT) Received: from postgresql.org ([200.46.204.71]) by localhost (mx1.hub.org [200.46.204.128]) (amavisd-new, port 10024) with ESMTP id 70292-01 for ; Tue, 18 Jul 2006 00:22:52 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey- Received: from linda-1.paradise.net.nz (bm-1a.paradise.net.nz [203.96.152.180]) by postgresql.org (Postfix) with ESMTP id 67FA49F9316 for ; Mon, 17 Jul 2006 21:22:53 -0300 (ADT) Received: from smtp-3.paradise.net.nz (tclsnelb1-src-1.paradise.net.nz [203.96.152.172]) by linda-1.paradise.net.nz (Paradise.net.nz) with ESMTP id <0J2K00JHKP21WV@linda-1.paradise.net.nz> for pgsql-performance@postgresql.org; Tue, 18 Jul 2006 12:22:50 +1200 (NZST) Received: from [192.168.1.11] (218-101-28-217.dsl.clear.net.nz [218.101.28.217]) by smtp-3.paradise.net.nz (Postfix) with ESMTP id 3C6D4BBA4A5; Tue, 18 Jul 2006 12:22:49 +1200 (NZST) Date: Tue, 18 Jul 2006 12:22:29 +1200 From: Mark Kirkwood Subject: Re: RAID stripe size question In-reply-to: <7F10D26ECFA1FB458B89C5B4B0D72C2B4E4BDF@sesrv12.wirelesscar.com> To: Mikael Carneholm Cc: Markus Schaber , pgsql-performance@postgresql.org Message-id: <44BC29C5.5090607@paradise.net.nz> MIME-version: 1.0 Content-type: text/plain; format=flowed; charset=ISO-8859-1 Content-transfer-encoding: 7bit User-Agent: Thunderbird 1.5.0.4 (X11/20060704) References: <7F10D26ECFA1FB458B89C5B4B0D72C2B4E4BDF@sesrv12.wirelesscar.com> X-Virus-Scanned: Maia Mailguard 1.0.1 X-Archive-Number: 200607/171 X-Sequence-Number: 20031 Mikael Carneholm wrote: > > Btw, here's the bonnie++ results from two different array sets (10+18, > 4+24) on the MSA1500: > > > LUN: DATA, 24 disks, stripe size 64K > ------------------------------------- > Version 1.03 ------Sequential Output------ --Sequential Input- > --Random- > -Per Chr- --Block-- -Rewrite- -Per Chr- --Block-- > --Seeks-- > Machine Size K/sec %CP K/sec %CP K/sec %CP K/sec %CP K/sec %CP > /sec %CP > sesell01 32G 59443 97 118515 39 25023 5 30926 49 60835 6 > 531.8 1 > ------Sequential Create------ --------Random > Create-------- > -Create-- --Read--- -Delete-- -Create-- --Read--- > -Delete-- > files /sec %CP /sec %CP /sec %CP /sec %CP /sec %CP > /sec %CP > 16 2499 90 +++++ +++ +++++ +++ 2817 99 +++++ +++ > 10971 100 > It might be interesting to see if 128K or 256K stripe size gives better sequential throughput, while still leaving the random performance ok. Having said that, the seeks/s figure of 531 not that great - for instance I've seen a 12 disk (15K SCSI) system report about 1400 seeks/s in this test. Sorry if you mentioned this already - but what OS and filesystem are you using? (if Linux and ext3, it might be worth experimenting with xfs or jfs). Cheers Mark