Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752497AbXIYJNt (ORCPT ); Tue, 25 Sep 2007 05:13:49 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751119AbXIYJNl (ORCPT ); Tue, 25 Sep 2007 05:13:41 -0400 Received: from mx3.mail.elte.hu ([157.181.1.138]:55777 "EHLO mx3.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751082AbXIYJNk (ORCPT ); Tue, 25 Sep 2007 05:13:40 -0400 Date: Tue, 25 Sep 2007 11:13:31 +0200 From: Ingo Molnar To: Mike Galbraith Cc: linux-kernel@vger.kernel.org, Peter Zijlstra , Srivatsa Vaddagiri , Dhaval Giani , Dmitry Adamushko , Andrew Morton Subject: Re: [git] CFS-devel, latest code Message-ID: <20070925091331.GA22905@elte.hu> References: <20070924214537.GA18980@elte.hu> <1190700652.6482.7.camel@Homer.simpson.net> <1190705759.11910.10.camel@Homer.simpson.net> <1190709207.11226.6.camel@Homer.simpson.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1190709207.11226.6.camel@Homer.simpson.net> User-Agent: Mutt/1.5.14 (2007-02-12) 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 Content-Length: 1315 Lines: 35 * Mike Galbraith wrote: > > sched_debug (attached) is.. strange. > > Disabling CONFIG_FAIR_GROUP_SCHED fixed both. [...] heh. Evil plan to enable the group scheduler by default worked out as planned! ;-) [guess how many container users would do ... interactivity tests like you do??] > [...] Latencies of up to 336ms hit me during the recompile (make -j3), > with nothing else running. Since reboot, latencies are, so far, very > very nice. [...] 'very very nice' == 'best ever' ? :-) > [...] I'm leaving it disabled for now. ok, i'm too seeing some sort of latency weirdness with CONFIG_FAIR_GROUP_SCHED enabled, _if_ there's Xorg involved which runs under root uid on my box - and hence gets 50% of all CPU time. Srivatsa, any ideas? It could either be an accounting buglet (less likely, seems like the group scheduling bits stick to the 50% splitup nicely), or a preemption buglet. One potential preemption buglet would be for the group scheduler to not properly preempt a running task when a task from another uid is woken? 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/