From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754059AbYAPQiv (ORCPT ); Wed, 16 Jan 2008 11:38:51 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752184AbYAPQil (ORCPT ); Wed, 16 Jan 2008 11:38:41 -0500 Received: from wx-out-0506.google.com ([66.249.82.234]:49378 "EHLO wx-out-0506.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752199AbYAPQij (ORCPT ); Wed, 16 Jan 2008 11:38:39 -0500 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; b=ajMTKplD8YJrFVjMTFnWmZRPqcLFCaaJ1fDtY7izwOuIznVQLLmCIQRrR2TmKGBr2kcEVTkOQYxwDLLW3cWwQy4NRQN67tEDF1oQyM0C5Wa7imJm8y9Hbb3DVZ0oCzSsyOD5XCvR+7Uzujqb1cmtHZXsyYVkIBkYCskb9vkgE0s= Message-ID: Date: Wed, 16 Jan 2008 16:38:33 +0000 From: "Colin Fowler" To: "Ingo Molnar" Subject: Re: Performance loss 2.6.22->22.6.23->2.6.24-rc7 on CPU intensive benchmark on 8 Core Xeon Cc: linux-kernel@vger.kernel.org, "Peter Zijlstra" In-Reply-To: <20080116161951.GA15000@elte.hu> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <20080114185520.GA26540@elte.hu> <20080115220641.GC2665@elte.hu> <20080116153505.GB18553@elte.hu> <20080116161951.GA15000@elte.hu> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Ingo, I have permission for a binary only release (mailed the supervisor intermediately after your earler mail). I'm sure the abstract code simulating the workload will be alright too, but I need time to put it together as I'm a bit swamped at the moment. Will hope to have it in the next few days. regards, Colin On Jan 16, 2008 4:19 PM, Ingo Molnar wrote: > > * Colin Fowler wrote: > > > Hi Ingo, I'll need to convince my supervisor first if I can release a > > binary. Technically anythin glike this needs to go through our > > University's "innovations department" and requires lengthy paperwork > > and NDAs :(. > > a binary wouldnt work for me anyway. But you could try to write a > "workload simulator": just pick out the pthread ops and replace the > worker functions with some dummy stuff that just touches an array that > has similar size to the tiles (in a tight loop). Make sure it has > similar context-switch rate and idle percentage as your real workload - > then send us the .c file. As long as it's a single .c file that runs for > a few seconds and outputs a precise enough "run time" result, kernel > developers would pick it up and use it for optimizations. To get the # > of cpus automatically you can do: > > cpus = system("exit `grep processor /proc/cpuinfo | wc -l`"); > cpus = WEXITSTATUS(cpus); > > and start as many threads as many CPUs there are in the system. > > Ingo >