From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S270271AbTGRSE3 (ORCPT ); Fri, 18 Jul 2003 14:04:29 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S270272AbTGRSE3 (ORCPT ); Fri, 18 Jul 2003 14:04:29 -0400 Received: from e32.co.us.ibm.com ([32.97.110.130]:58600 "EHLO e32.co.us.ibm.com") by vger.kernel.org with ESMTP id S270271AbTGRSE1 (ORCPT ); Fri, 18 Jul 2003 14:04:27 -0400 Date: Fri, 18 Jul 2003 11:18:50 -0700 From: Mike Kravetz To: Erich Focht Cc: LSE , linux-kernel Subject: Re: [Lse-tech] [patch 2.6.0-test1] per cpu times Message-ID: <20030718111850.C1627@w-mikek2.beaverton.ibm.com> References: <200307181835.42454.efocht@hpce.nec.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.2.5.1i In-Reply-To: <200307181835.42454.efocht@hpce.nec.com>; from efocht@hpce.nec.com on Fri, Jul 18, 2003 at 06:35:42PM +0200 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Jul 18, 2003 at 06:35:42PM +0200, Erich Focht wrote: > > This patch brings back the per CPU user & system times which one was > used to see in /proc/PID/cpu with 2.4 kernels. Useful for SMP and NUMA > scheduler development, needed for reasonable output in numabench / > numa_test. > On a somewhat related note ... We (Big Blue) have a performance reporting application that would like to know how long a task sits on a runqueue before it is actually given the CPU. In other words, it wants to know how long the 'runnable task' was delayed due to contention for the CPU(s). Of course, one could get an overall feel for this based on total runqueue length. However, this app would really like this info on a per-task basis. Does anyone else think this type of info would be useful? A patch to compute/export this info should be straight forward to implement. -- Mike