Received: from localhost (unknown [200.46.204.182]) by postgresql.org (Postfix) with ESMTP id 02F172E0186 for ; Mon, 26 Nov 2007 19:06:39 -0400 (AST) Received: from postgresql.org ([200.46.204.71]) by localhost (mx1.hub.org [200.46.204.182]) (amavisd-maia, port 10024) with ESMTP id 03898-06 for ; Mon, 26 Nov 2007 19:06:32 -0400 (AST) Received: from sss.pgh.pa.us (sss.pgh.pa.us [66.207.139.130]) by postgresql.org (Postfix) with ESMTP id EC1672E0180 for ; Mon, 26 Nov 2007 19:06:35 -0400 (AST) Received: from sss2.sss.pgh.pa.us (tgl@localhost [127.0.0.1]) by sss.pgh.pa.us (8.14.1/8.14.1) with ESMTP id lAQN6Y05005105; Mon, 26 Nov 2007 18:06:34 -0500 (EST) To: Damon Hart cc: pgsql-performance@postgresql.org Subject: Re: PostgreSQL performance on various distribution stock kernels In-reply-to: <1196117408.19996.16.camel@xw1.bbd> References: <1196117408.19996.16.camel@xw1.bbd> Comments: In-reply-to Damon Hart message dated "Mon, 26 Nov 2007 17:50:08 -0500" Date: Mon, 26 Nov 2007 18:06:34 -0500 Message-ID: <5104.1196118394@sss.pgh.pa.us> From: Tom Lane X-Virus-Scanned: Maia Mailguard 1.0.1 X-Archive-Number: 200711/310 X-Sequence-Number: 27725 Damon Hart writes: > So, what's different between these tests? I'm seeing performance > differences of between +65% to +90% transactions per second of the > OpenVZ kernel running on the HN over the stock Fedora 8 kernel. Is > this reflective of different emphasis between RHEL and Fedora kernel > builds? Some OpenVZ optimization on top of the RHEL5 build? Something > else? Where should I look? Considering how raw Fedora 8 is, I think what you've probably found is a performance bug that should be reported to the kernel hackers. Just to confirm: this *is* the same filesystem in both cases, right? regards, tom lane