Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754592AbXJ3H1U (ORCPT ); Tue, 30 Oct 2007 03:27:20 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753053AbXJ3H1M (ORCPT ); Tue, 30 Oct 2007 03:27:12 -0400 Received: from mx2.mail.elte.hu ([157.181.151.9]:57065 "EHLO mx2.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752734AbXJ3H1L (ORCPT ); Tue, 30 Oct 2007 03:27:11 -0400 Date: Tue, 30 Oct 2007 08:26:58 +0100 From: Ingo Molnar To: "Zhang, Yanmin" Cc: LKML , Peter Zijlstra Subject: Re: aim7 -30% regression in 2.6.24-rc1 Message-ID: <20071030072658.GB20372@elte.hu> References: <1193391787.3019.174.camel@ymzhang> <20071026112307.GA30406@elte.hu> <1193624538.3019.189.camel@ymzhang> <1193650626.3019.198.camel@ymzhang> <1193710325.3019.203.camel@ymzhang> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1193710325.3019.203.camel@ymzhang> 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: 0.0002] Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1233 Lines: 32 * Zhang, Yanmin wrote: > sub-bisecting captured patch > 38ad464d410dadceda1563f36bdb0be7fe4c8938(sched: uniform tunings) > caused 20% regression of aim7. > > The last 10% should be also related to sched parameters, such like > sysctl_sched_min_granularity. ah, interesting. Since you have CONFIG_SCHED_DEBUG enabled, could you please try to figure out what the best value for /proc/sys/kernel_sched_latency, /proc/sys/kernel_sched_nr_latency and /proc/sys/kernel_sched_min_granularity is? there's a tuning constraint for kernel_sched_nr_latency: - kernel_sched_nr_latency should always be set to kernel_sched_latency/kernel_sched_min_granularity. (it's not a free tunable) i suspect a good approach would be to double the value of kernel_sched_latency and kernel_sched_nr_latency in each tuning iteration, while keeping kernel_sched_min_granularity unchanged. That will excercise the tuning values of the 2.6.23 kernel as well. 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/