From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754283AbXLEUrU (ORCPT ); Wed, 5 Dec 2007 15:47:20 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751656AbXLEUrN (ORCPT ); Wed, 5 Dec 2007 15:47:13 -0500 Received: from mx3.mail.elte.hu ([157.181.1.138]:46600 "EHLO mx3.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751617AbXLEUrM (ORCPT ); Wed, 5 Dec 2007 15:47:12 -0500 Date: Wed, 5 Dec 2007 21:46:46 +0100 From: Ingo Molnar To: Jie Chen Cc: Simon Holm Th??gersen , Eric Dumazet , linux-kernel@vger.kernel.org, Peter Zijlstra Subject: Re: Possible bug from kernel 2.6.22 and above, 2.6.24-rc4 Message-ID: <20071205204645.GC25694@elte.hu> References: <1195698770.11808.4.camel@odie.local> <4744F042.4070002@jlab.org> <20071204131707.GA4232@elte.hu> <4756C3D9.9030107@jlab.org> <20071205154014.GA6491@elte.hu> <4756D058.1070500@jlab.org> <20071205164723.GA25641@elte.hu> <4756E44E.8080607@jlab.org> <20071205200343.GA14570@elte.hu> <475708A7.4030708@jlab.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <475708A7.4030708@jlab.org> User-Agent: Mutt/1.5.17 (2007-11-01) 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 * Jie Chen wrote: > I just disabled the affinity mask and reran the test. There were no > significant changes for two threads (barrier overhead is around 9 > microseconds). As for 8 threads, the barrier overhead actually drops a > little, which is good. Let me know whether I can be any help. Thank > you very much. sorry to be dense, but could you give me instructions how i could remove the affinity mask and test the "barrier overhead" myself? I have built "pthread_sync" and it outputs numbers for me - which one would be the barrier overhead: Reference_time_1 ? Ingo