From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262005AbVDDEZM (ORCPT ); Mon, 4 Apr 2005 00:25:12 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262009AbVDDEZM (ORCPT ); Mon, 4 Apr 2005 00:25:12 -0400 Received: from smtp-roam.Stanford.EDU ([171.64.10.152]:41372 "EHLO smtp-roam.Stanford.EDU") by vger.kernel.org with ESMTP id S262005AbVDDEZH (ORCPT ); Mon, 4 Apr 2005 00:25:07 -0400 Message-ID: <4250C19F.9070801@myrealbox.com> Date: Sun, 03 Apr 2005 21:25:03 -0700 From: Andy Lutomirski User-Agent: Mozilla Thunderbird 1.0 (Windows/20041206) X-Accept-Language: en-us, en MIME-Version: 1.0 To: Paul Jackson CC: kenneth.w.chen@intel.com, torvalds@osdl.org, nickpiggin@yahoo.com.au, akpm@osdl.org, linux-kernel@vger.kernel.org Subject: Re: [patch] sched: auto-tune migration costs [was: Re: Industry db benchmark result on recent 2.6 kernels] References: <200504020100.j3210fg04870@unix-os.sc.intel.com> <20050402145351.GA11601@elte.hu> <20050402215332.79ff56cc.pj@engr.sgi.com> <20050403070415.GA18893@elte.hu> <20050403043420.212290a8.pj@engr.sgi.com> In-Reply-To: <20050403043420.212290a8.pj@engr.sgi.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Paul Jackson wrote: > Ok - that flies, or at least walks. It took 53 seconds to > compute this cost matrix. Not that I really know what I'm talking about here, but this sounds highly parallelizable. It seems like you could do N/2 measurements at a time, so this should be O(N) to compute the matrix (ignoring issues of how long it takes to write the data to memory, but that should be insignificant). Even if you can't parallelize it all the way, it ought to at least help. --Andy