Received: from localhost (maia-4.hub.org [200.46.204.183]) by postgresql.org (Postfix) with ESMTP id 8FE459FB5A8 for ; Thu, 1 Mar 2007 22:21:20 -0400 (AST) Received: from postgresql.org ([200.46.204.71]) by localhost (mx1.hub.org [200.46.204.183]) (amavisd-new, port 10024) with ESMTP id 77042-05 for ; Thu, 1 Mar 2007 22:21:17 -0400 (AST) X-Greylist: from auto-whitelisted by SQLgrey-1.7.4 Received: from lists.commandprompt.com (host-254.commandprompt.net [207.173.203.254]) by postgresql.org (Postfix) with ESMTP id A6BB69FB53A for ; Thu, 1 Mar 2007 22:21:17 -0400 (AST) Received: from [192.168.1.50] (or-67-76-146-141.sta.embarqhsd.net [67.76.146.141]) (authenticated bits=0) by lists.commandprompt.com (8.13.7/8.13.6) with ESMTP id l222L9sB013227 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Thu, 1 Mar 2007 18:21:10 -0800 Message-ID: <45E78A30.1030408@commandprompt.com> Date: Thu, 01 Mar 2007 18:21:36 -0800 From: "Joshua D. Drake" Organization: Command Prompt, Inc. User-Agent: Thunderbird 1.5.0.9 (X11/20070103) MIME-Version: 1.0 To: Alex Deucher CC: Jeff Frost , pgsql-performance@postgresql.org Subject: Re: strange performance regression between 7.4 and 8.1 References: <45E73C90.2080206@commandprompt.com> <45E78210.9030401@commandprompt.com> In-Reply-To: X-Enigmail-Version: 0.94.0.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit X-Virus-Scanned: ClamAV version 0.88.5, clamav-milter version 0.88.5 on projects.commandprompt.com X-Virus-Status: Clean X-Greylist: Sender succeded SMTP AUTH authentication, not delayed by milter-greylist-1.6 (lists.commandprompt.com [192.168.2.159]); Thu, 01 Mar 2007 18:21:10 -0800 (PST) X-Virus-Scanned: Maia Mailguard 1.0.1 X-Spam-Status: No, hits=0.075 tagged_above=0 required=5 tests=AWL, BAYES_50, FORGED_RCVD_HELO X-Spam-Level: X-Archive-Number: 200703/41 X-Sequence-Number: 23446 Alex Deucher wrote: > On 3/1/07, Joshua D. Drake wrote: >> \ >> >> Is the SAN being shared between the database servers and other >> >> servers? Maybe >> >> it was just random timing that gave you the poor write performance on >> >> the old >> >> server which might be also yielding occassional poor performance on >> >> the new >> >> one. >> >> >> > >> > The direct attached scsi discs on the old database server we getting >> > 45MBps not the SAN. The SAN got 62/145Mbps, which is not as bad. >> >> How many spindles you got in that SAN? > > 105 IIRC. You have 105 spindles are you are only get 62megs on writes? That seems about half what you should be getting. (at least). Joshua D. Drake > > Alex > -- === The PostgreSQL Company: Command Prompt, Inc. === Sales/Support: +1.503.667.4564 || 24x7/Emergency: +1.800.492.2240 Providing the most comprehensive PostgreSQL solutions since 1997 http://www.commandprompt.com/ Donate to the PostgreSQL Project: http://www.postgresql.org/about/donate PostgreSQL Replication: http://www.commandprompt.com/products/