From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756849AbXFPNVt (ORCPT ); Sat, 16 Jun 2007 09:21:49 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754980AbXFPNVl (ORCPT ); Sat, 16 Jun 2007 09:21:41 -0400 Received: from ausmtp04.au.ibm.com ([202.81.18.152]:49974 "EHLO ausmtp04.au.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754831AbXFPNVk (ORCPT ); Sat, 16 Jun 2007 09:21:40 -0400 Message-ID: <4673E3D9.2020300@linux.vnet.ibm.com> Date: Sat, 16 Jun 2007 18:51:29 +0530 From: Balbir Singh Reply-To: balbir@linux.vnet.ibm.com Organization: IBM User-Agent: Thunderbird 1.5.0.12 (X11/20070604) MIME-Version: 1.0 To: malc CC: Ingo Molnar , linux-kernel@vger.kernel.org, Dmitry Adamushko Subject: Re: [patch] sched: accurate user accounting References: <200703251159.03616.kernel@kolivas.org> <200703260901.54943.kernel@kolivas.org> <200703260957.34798.kernel@kolivas.org> <20070328113743.GA5615@elte.hu> <20070614204253.GA14076@elte.hu> <20070614211828.GA21243@elte.hu> <46720B19.5000006@linux.vnet.ibm.com> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org malc wrote: > On Fri, 15 Jun 2007, Balbir Singh wrote: > >> malc wrote: >>> On Thu, 14 Jun 2007, Ingo Molnar wrote: >>> > > [..snip..] > >>> >>> Now integral load matches the one obtained via the "accurate" method. >>> However the report for individual cores are of by around 20% percent. >>> >> >> I think I missed some of the context, is the accounting of individual >> tasks >> or cpustat values off by 20%? I'll try and reproduce this problem. > > Neither actually, the individual core idle times reported via `/proc/stat' > are off by 20 percent, one over estimates and the other under estimates > and the sum is right on the mark. > Interesting, the idle time accounting (done from account_system_time()) has not changed. Has your .config changed? Could you please send it across. I've downloaded apc and I am trying to reproduce your problem. >> >> Could you provide more details on the APC tool that you are using -- I >> do not understand the orange and yellow lines, do they represent system >> and user time? > > It's somewhat documented on the page: http://www.boblycat.org/~malc/apc > Anyway the left bar is based on information from `/proc/stat' the right > one is derived from the kernel module that just times how much time was > spent in idle handler. The graphs: red - `/proc/stat', yellow - module. > >> NOTE: There is some inconsistency in the values reported by /usr/bin/time >> (getrusage) and values reported in /proc or through delay accounting. > > I don't really use `getrusage'. > Tools like /usr/bin/time do. -- Warm Regards, Balbir Singh Linux Technology Center IBM, ISTL