From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753456AbZHTG3m (ORCPT ); Thu, 20 Aug 2009 02:29:42 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752275AbZHTG3m (ORCPT ); Thu, 20 Aug 2009 02:29:42 -0400 Received: from bilbo.ozlabs.org ([203.10.76.25]:47884 "EHLO bilbo.ozlabs.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751313AbZHTG3l (ORCPT ); Thu, 20 Aug 2009 02:29:41 -0400 Date: Thu, 20 Aug 2009 16:24:51 +1000 From: Anton Blanchard To: KAMEZAWA Hiroyuki Cc: Peter Zijlstra , balbir@linux.vnet.ibm.com, Bharata B Rao , KOSAKI Motohiro , Ingo Molnar , mingo@redhat.com, hpa@zytor.com, linux-kernel@vger.kernel.org, schwidefsky@de.ibm.com, balajirrao@gmail.com, dhaval@linux.vnet.ibm.com, tglx@linutronix.de, akpm@linux-foundation.org Subject: Re: [tip:sched/core] sched: cpuacct: Use bigger percpu counter batch values for stats counters Message-ID: <20090820062451.GH21100@kryten> References: <20090512102412.GG6351@balbir.in.ibm.com> <20090512102939.GB11714@elte.hu> <20090512193656.D647.A69D9226@jp.fujitsu.com> <20090716081010.GB3134@in.ibm.com> <20090716083948.GA2950@kryten> <20090820051038.GF21100@kryten> <20090820052605.GC26265@balbir.in.ibm.com> <1250747579.8282.110.camel@twins> <20090820060528.GG21100@kryten> <20090820151017.2ba95d6e.kamezawa.hiroyu@jp.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20090820151017.2ba95d6e.kamezawa.hiroyu@jp.fujitsu.com> User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, > Could you share contex-switch-test program ? > I'd like to play with it to find out what I can do against percpu counter. Sure: http://ozlabs.org/~anton/junkcode/context_switch.c Very simple, just run it once per core: for i in `seq 0 31` do taskset -c $i ./context_switch & done Then look at the context switch rates in vmstat. Anton