X-Original-To: pgsql-performance-postgresql.org@localhost.postgresql.org Received: from localhost (unknown [200.46.204.144]) by svr1.postgresql.org (Postfix) with ESMTP id 912E0545B5 for ; Mon, 25 Apr 2005 04:01:14 -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 16631-04 for ; Mon, 25 Apr 2005 07:01:04 +0000 (GMT) Received: from mail.tecarta.com (66.238.115.135.ptr.us.xo.net [66.238.115.135]) by svr1.postgresql.org (Postfix) with ESMTP id 2C4BF54553 for ; Mon, 25 Apr 2005 04:00:43 -0300 (ADT) Received: from mail pickup service by mail.tecarta.com with Microsoft SMTPSVC; Mon, 25 Apr 2005 00:03:47 -0700 Received: from mail.tecarta.com ([192.168.160.2]) by mail.tecarta.com with Microsoft SMTPSVC(6.0.3790.0); Mon, 25 Apr 2005 00:03:45 -0700 Received: from barracuda.tecarta.com ([192.168.160.200]) by mail.tecarta.com (SAVSMTP 3.1.0.29) with SMTP id M2005042500034527372 for ; Mon, 25 Apr 2005 00:03:45 -0700 X-ASG-Debug-ID: 1114412440-5962-0-0 X-Barracuda-URL: http://192.168.160.200:8000/cgi-bin/mark.cgi Received: from mail2 (mail2.hq.corp [192.168.160.6]) by barracuda.tecarta.com (Spam Firewall) with SMTP id 45575202C5C5 for ; Mon, 25 Apr 2005 00:00:40 -0700 (PDT) Received: from [192.168.0.13] ([63.206.203.145]) by mail.tecarta.com with Microsoft SMTPSVC(6.0.3790.0); Mon, 25 Apr 2005 00:01:40 -0700 Message-ID: <426C9508.8030902@sfnet.cc> Date: Sun, 24 Apr 2005 23:58:16 -0700 From: Steve Poe User-Agent: Mozilla Thunderbird 1.0 (X11/20041228) X-Accept-Language: en-us, en MIME-Version: 1.0 To: "Thomas F.O'Connell" Cc: PgSQL - Performance X-ASG-Orig-Subj: Re: [PERFORM] pgbench Comparison of 7.4.7 to 8.0.2 Subject: Re: pgbench Comparison of 7.4.7 to 8.0.2 References: <2784476415a96bb0912ebca41edb3d84@sitening.com> <6865.1113600214@sss.pgh.pa.us> In-Reply-To: Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit X-OriginalArrivalTime: 25 Apr 2005 07:01:40.0765 (UTC) FILETIME=[A1A85CD0:01C54964] X-Virus-Scanned: by Barracuda Spam Firewall at tecarta.com X-Barracuda-Spam-Score: 0.00 X-Barracuda-Spam-Status: No, SCORE=0.00 using global scores of TAG_LEVEL=4.0 QUARANTINE_LEVEL=1000.0 KILL_LEVEL=7.0 tests=BAYES_50 X-Barracuda-Spam-Report: Code version 3.02, rules version 3.0.536 Rule breakdown below pts rule name description ---- ---------------------- -------------------------------------------------- 0.00 BAYES_50 BODY: Bayesian spam probability is 40 to 60% [score: 0.5000] X-Virus-Scanned: by amavisd-new at hub.org X-Spam-Status: No, hits=0.182 tagged_above=0 required=5 tests=AWL, FORGED_RCVD_HELO X-Spam-Level: X-Archive-Number: 200504/670 X-Sequence-Number: 12067 >There was some interesting oscillation behavior in both version of postgres that occurred with 25 >clients and 1000 transactions at a scaling factor of 100. This was repeatable with the distribution >version of pgbench run iteratively from the command line. I'm not sure how to explain this. Tom, When you see these oscillations, do they occur after so many generated results? Some oscillation is normal, in my opinion, from 10-15% of the performance is noise-related. The key is to tune the server that you either 1) minimize the oscillation and/or 2)increase your overall performance above the 10-15% baseline, and 3) find out what the mean and standard deviation between all your results. If your results are within that range, this maybe "normal". I follow-up with you later on what I do. Steve Poe