Received: from localhost (unknown [200.46.204.183]) by developer.postgresql.org (Postfix) with ESMTP id 18FB92E0032 for ; Fri, 18 Apr 2008 14:19:25 -0300 (ADT) Received: from developer.postgresql.org ([200.46.204.71]) by localhost (mx1.hub.org [200.46.204.183]) (amavisd-maia, port 10024) with ESMTP id 13791-01 for ; Fri, 18 Apr 2008 14:19:12 -0300 (ADT) X-Greylist: from auto-whitelisted by SQLgrey-1.7.5 Received: from westnet.com (westnet.com [216.187.52.2]) by developer.postgresql.org (Postfix) with ESMTP id 7DAB22E0060 for ; Fri, 18 Apr 2008 14:19:12 -0300 (ADT) Received: from westnet.com (localhost [127.0.0.1]) by westnet.com (8.14.0/8.14.0) with ESMTP id m3IHJAW5007237; Fri, 18 Apr 2008 13:19:10 -0400 (EDT) Received: from localhost (gsmith@localhost) by westnet.com (8.14.0/8.13.2/Submit) with ESMTP id m3IHJ9iI007234; Fri, 18 Apr 2008 13:19:10 -0400 (EDT) X-Authentication-Warning: westnet.com: gsmith owned process doing -bs Date: Fri, 18 Apr 2008 13:19:09 -0400 (EDT) From: Greg Smith X-X-Sender: gsmith@westnet.com To: Matthew cc: pgsql-performance@postgresql.org Subject: Re: Strange behavior: pgbench and new Linux kernels In-Reply-To: Message-ID: References: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed X-Virus-Scanned: Maia Mailguard 1.0.1 X-Archive-Number: 200804/271 X-Sequence-Number: 29764 On Fri, 18 Apr 2008, Matthew wrote: > You may also be seeing processes forced to switch between CPUs, which > breaks the caches even more. So what happens if you run pgbench on a > separate machine to the server? Does the problem still exist in that > case? I haven't run that test yet but will before I submit a report. I did however try running things with the pgbench executable itself bound to a single CPU with no improvement. -- * Greg Smith gsmith@gregsmith.com http://www.gregsmith.com Baltimore, MD