Received: from maia.hub.org (maia-5.hub.org [200.46.204.29]) by mail.postgresql.org (Postfix) with ESMTP id 9B9C4632445 for ; Fri, 25 Jun 2010 16:03:44 -0300 (ADT) Received: from mail.postgresql.org ([200.46.204.86]) by maia.hub.org (mx1.hub.org [200.46.204.29]) (amavisd-maia, port 10024) with ESMTP id 73984-02 for ; Fri, 25 Jun 2010 19:03:37 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from moutng.kundenserver.de (moutng.kundenserver.de [212.227.17.9]) by mail.postgresql.org (Postfix) with ESMTP id EBBFA63271D for ; Fri, 25 Jun 2010 16:03:36 -0300 (ADT) Received: from [75.197.236.239] (239.sub-75-197-236.myvzw.com [75.197.236.239]) by mrelayeu.kundenserver.de (node=mreu1) with ESMTP (Nemesis) id 0MXTpy-1Oeks72JHS-00W8Ho; Fri, 25 Jun 2010 21:03:34 +0200 Message-ID: <4C24FD82.4070100@2ndquadrant.com> Date: Fri, 25 Jun 2010 15:03:30 -0400 From: Greg Smith User-Agent: Thunderbird 2.0.0.24 (X11/20100317) MIME-Version: 1.0 To: Craig James CC: pgsql-performance@postgresql.org Subject: Re: pgbench results on a new server References: <4BBCFB12.1010306@emolecules.com> <4BBD3A17.90209@emolecules.com> <4C23FD52.40508@emolecules.com> <23596.1277438692@sss.pgh.pa.us> <4C24B3BB.3070901@emolecules.com> <2286.1277477230@sss.pgh.pa.us> <4C24D679.7030701@emolecules.com> <6203.1277485291@sss.pgh.pa.us> <4C24FB0D.4020701@emolecules.com> In-Reply-To: <4C24FB0D.4020701@emolecules.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Provags-ID: V01U2FsdGVkX1+LLF4dr/ZGlH5Ds8ljWlE1C2lmHF3lDj+8h40 SOqnCqmdJj1rAW62vNt0zbzhoQQwE3KiibtOxfNdtSOelf0pu5 ck9OxkNcVG3Cl26Upq3eBLzZClwjceh 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, RCVD_IN_DNSWL_NONE=-0.0001 X-Spam-Level: X-Archive-Number: 201006/482 X-Sequence-Number: 39338 Craig James wrote: > I've got a new server and want to make sure it's running well. Any changes to the postgresql.conf file? Generally you need at least a moderate shared_buffers (1GB or so at a minimum) and checkpoint_segments (32 or higher) in order for the standard pgbench test to give good results. > pgbench -c20 -t 5000 -U test > tps = 5789 > pgbench -c30 -t 3333 -U test > tps = 6961 > pgbench -c40 -t 2500 -U test > tps = 2945 General numbers are OK, the major drop going from 30 to 40 clients is larger than it should be. I'd suggest running the 40 client count one again to see if that's consistent. If it is, that may just be pgbench itself running into a problem. It doesn't handle high client counts very well unless you use the 9.0 version that supports multiple pgbench workers with the "-j" option. -- Greg Smith 2ndQuadrant US Baltimore, MD PostgreSQL Training, Services and Support greg@2ndQuadrant.com www.2ndQuadrant.us