Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757191Ab3J1Qtr (ORCPT ); Mon, 28 Oct 2013 12:49:47 -0400 Received: from mail-pb0-f53.google.com ([209.85.160.53]:52747 "EHLO mail-pb0-f53.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756591Ab3J1Qtp (ORCPT ); Mon, 28 Oct 2013 12:49:45 -0400 Message-ID: <526E95A1.7080701@gmail.com> Date: Mon, 28 Oct 2013 10:49:37 -0600 From: David Ahern User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.8; rv:24.0) Gecko/20100101 Thunderbird/24.0.1 MIME-Version: 1.0 To: Ingo Molnar , Neil Horman CC: Eric Dumazet , linux-kernel@vger.kernel.org, sebastien.dugue@bull.net, Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , x86@kernel.org, netdev@vger.kernel.org Subject: Re: [PATCH] x86: Run checksumming in parallel accross multiple alu's References: <1381510298-20572-1-git-send-email-nhorman@tuxdriver.com> <20131012172124.GA18241@gmail.com> <20131014202854.GH26880@hmsreliant.think-freely.org> <1381785560.2045.11.camel@edumazet-glaptop.roam.corp.google.com> <1381789127.2045.22.camel@edumazet-glaptop.roam.corp.google.com> <20131017003421.GA31470@hmsreliant.think-freely.org> <20131017084121.GC22705@gmail.com> <20131028160131.GA31048@hmsreliant.think-freely.org> <20131028162438.GB14350@gmail.com> In-Reply-To: <20131028162438.GB14350@gmail.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 738 Lines: 22 On 10/28/13 10:24 AM, Ingo Molnar wrote: > The most accurate method of measurement for such single-threaded > workloads is something like: > > taskset 0x1 perf stat -a -C 1 --repeat 20 ... > > this will bind your workload to CPU#0, and will do PMU measurements > only there - without mixing in other CPUs or workloads. you can drop the -a if you only want a specific CPU (-C arg). And -C in perf is cpu number starting with 0, so in your example above -C 1 means cpu1, not cpu0. David -- 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/