From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757417AbXJaJzk (ORCPT ); Wed, 31 Oct 2007 05:55:40 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755027AbXJaJzd (ORCPT ); Wed, 31 Oct 2007 05:55:33 -0400 Received: from mx2.mail.elte.hu ([157.181.151.9]:54589 "EHLO mx2.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753627AbXJaJzc (ORCPT ); Wed, 31 Oct 2007 05:55:32 -0400 Date: Wed, 31 Oct 2007 10:55:17 +0100 From: Ingo Molnar To: Nick Piggin Cc: Lorenzo Allegrucci , Bj?rn , linux-kernel@vger.kernel.org, Peter Zijlstra Subject: Re: 2.6.23 performance regression Message-ID: <20071031095517.GA5817@elte.hu> References: <4dcf7d360710300054m7ac77445pf786bd9044b572d7@mail.gmail.com> <200710311319.54210.nickpiggin@yahoo.com.au> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <200710311319.54210.nickpiggin@yahoo.com.au> User-Agent: Mutt/1.5.16 (2007-06-09) X-ELTE-VirusStatus: clean X-ELTE-SpamScore: -1.5 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-1.5 required=5.9 tests=BAYES_00 autolearn=no SpamAssassin version=3.1.7-deb -1.5 BAYES_00 BODY: Bayesian spam probability is 0 to 1% [score: 0.0000] Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org * Nick Piggin wrote: > On Tuesday 30 October 2007 18:54, Lorenzo Allegrucci wrote: > > Hi, sorry if this is a faq but reading > > http://people.freebsd.org/~kris/scaling/7.0%20Preview.pdf (slides 17, > > 18) > > looks like 2.6.23 is having a performance regression on MySQL and > > PostgreSQL benchmarks. Has anyone investigated these? > > I think Ingo was looking into them. I'm just in the middle of building > a new setup to investigate some performance issues too, so I hope to > look at this. > > Apparently it did go unnoticed during CFS testing, unfortunately. > Although now it has been brought to light, I think 2.6.24 is supposed > to be better (although it now gets worse on other things). yep. For those who fear the 1 million lines of code flux of 2.6.24, here's a backport of the scheduler changes to 2.6.23: http://people.redhat.com/mingo/cfs-scheduler/devel/sched-cfs-v2.6.23.1-v22.1-rc0.patch Lorenzo, could you please try that report back your reports? Thanks, Ingo