From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752800AbYHRHCO (ORCPT ); Mon, 18 Aug 2008 03:02:14 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751049AbYHRHB7 (ORCPT ); Mon, 18 Aug 2008 03:01:59 -0400 Received: from mx2.mail.elte.hu ([157.181.151.9]:51819 "EHLO mx2.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750885AbYHRHB7 (ORCPT ); Mon, 18 Aug 2008 03:01:59 -0400 Date: Mon, 18 Aug 2008 09:01:47 +0200 From: Ingo Molnar To: "Zhang, Yanmin" Cc: a.p.zijlstra@chello.nl, Linux Kernel Mailing List Subject: Re: scale sysctl_sched_shares_ratelimit with nr_cpus Message-ID: <20080818070147.GA4801@elte.hu> References: <37E52D09333DE2469A03574C88DBF40F024EBD2F@pdsmsx414.ccr.corp.intel.com> <20080818065220.GA2711@elte.hu> <37E52D09333DE2469A03574C88DBF40F024EBD69@pdsmsx414.ccr.corp.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <37E52D09333DE2469A03574C88DBF40F024EBD69@pdsmsx414.ccr.corp.intel.com> User-Agent: Mutt/1.5.18 (2008-05-17) 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=3.2.3 -1.5 BAYES_00 BODY: Bayesian spam probability is 0 to 1% [score: 0.0000] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org * Zhang, Yanmin wrote: > >>cool. It's already upstream (post-rc3 commit): > [YM] But comparing with 2.6.26, volanoMark result still has about 60% > regression. Does a scheduler trace show anything about why that drop happens? Do something like this to trace the scheduler: assuming debugfs is mounted under /debug and CONFIG_SCHED_TRACER=y: echo 1 > /debug/tracing/tracing_cpumask echo sched_switch > /debug/tracing/available_tracers cat /debug/tracing/trace_pipe > trace.txt ( regarding tracing_cpumask: trace only 1 CPU to make sure volanomark is not disturbed too much by many-CPUs tracing. ) Ingo