Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756209AbXH1Hgo (ORCPT ); Tue, 28 Aug 2007 03:36:44 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752081AbXH1Hgg (ORCPT ); Tue, 28 Aug 2007 03:36:36 -0400 Received: from mx2.mail.elte.hu ([157.181.151.9]:53475 "EHLO mx2.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751071AbXH1Hgf (ORCPT ); Tue, 28 Aug 2007 03:36:35 -0400 Date: Tue, 28 Aug 2007 09:36:19 +0200 From: Ingo Molnar To: Mike Galbraith Cc: Al Boldi , Linus Torvalds , Peter Zijlstra , Andrew Morton , linux-kernel@vger.kernel.org Subject: Re: CFS review Message-ID: <20070828073619.GA8267@elte.hu> References: <200708111344.42934.a1426z@gawab.com> <200708280737.53439.a1426z@gawab.com> <200708280823.53663.a1426z@gawab.com> <1188286097.6317.12.camel@Homer.simpson.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1188286097.6317.12.camel@Homer.simpson.net> 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: 0.0001] Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 972 Lines: 25 * Mike Galbraith wrote: > > I like your analysis, but how do you explain that these stalls > > vanish when __update_curr is disabled? > > When you disable __update_curr(), you're utterly destroying the > scheduler. There may well be a scheduler connection, but disabling > __update_curr() doesn't tell you anything meaningful. Basically, you're > letting all tasks run uninterrupted for just as long as they please > (which is why busy loops lock your box solid as a rock). I'd suggest > gathering some sched_debug stats or something... [...] the output of the following would be nice: http://people.redhat.com/mingo/cfs-scheduler/tools/cfs-debug-info.sh captured while the gears are running. 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/