Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756892AbXHBPm4 (ORCPT ); Thu, 2 Aug 2007 11:42:56 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752856AbXHBPmu (ORCPT ); Thu, 2 Aug 2007 11:42:50 -0400 Received: from mx2.mail.elte.hu ([157.181.151.9]:50462 "EHLO mx2.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752802AbXHBPmt (ORCPT ); Thu, 2 Aug 2007 11:42:49 -0400 Date: Thu, 2 Aug 2007 17:42:28 +0200 From: Ingo Molnar To: Kasper Sandberg Cc: Peter Zijlstra , Linus Torvalds , Linux Kernel Mailing List , ck@vds.kolivas.org Subject: Re: SD still better than CFS for 3d ?(was Re: 2.6.23-rc1) Message-ID: <20070802154228.GA12371@elte.hu> References: <1185536610.502.8.camel@localhost> <20070729170641.GA26220@elte.hu> <1185839164.27166.7.camel@localhost> <1185863461.3092.4.camel@twins> <20070731085713.GA15136@elte.hu> <1186011827.2482.1.camel@localhost> <20070802121018.GA11900@elte.hu> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20070802121018.GA11900@elte.hu> User-Agent: Mutt/1.5.14 (2007-02-12) X-ELTE-VirusStatus: clean X-ELTE-SpamScore: -1.0 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-1.0 required=5.9 tests=BAYES_00 autolearn=no SpamAssassin version=3.1.7-deb -1.0 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 Content-Length: 1509 Lines: 42 Kasper, could you please try the "chew-max" latency-printing utility: http://people.redhat.com/mingo/cfs-scheduler/tools/chew-max.c if you start it on an idle system it prints a single line: $ ./chew-max pid 14506, prio 0, interval of 99984800 nsec and prints nothing else. It continues looping and looping (using up 100% of CPU time), and the moment it's preempted, it prints a line about that preemption latency. Under higher load it will print something like this: out for 63 ms [max: 66], ran for 5 ms, load 7 out for 85 ms [max: 85], ran for 4 ms, load 5 out for 7 ms [max: 85], ran for 0 ms, load 0 out for 105 ms [max: 105], ran for 3 ms, load 3 out for 174 ms [max: 174], ran for 6 ms, load 3 out for 219 ms [max: 219], ran for 3 ms, load 1 out for 78 ms [max: 219], ran for 3 ms, load 3 so that we get a picture of your latencies, could you run this tool why you are seeing those 'bad' desktop latencies? (Since your CPU has two cores it might make sense to run two instances of chew-max.) record the latencies like this: ./chew-max > chew1.out & ./chew-max > chew2.out & and send us the chew1.out and chew2.out files (bzip2 -9 compressed). Thanks! Ingo - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/