Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758469AbXFPOIS (ORCPT ); Sat, 16 Jun 2007 10:08:18 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756204AbXFPOIM (ORCPT ); Sat, 16 Jun 2007 10:08:12 -0400 Received: from comtv.ru ([217.10.32.17]:53214 "EHLO comtv.ru" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755881AbXFPOIL (ORCPT ); Sat, 16 Jun 2007 10:08:11 -0400 X-UCL: actv Date: Sat, 16 Jun 2007 18:07:41 +0400 (MSD) From: malc X-X-Sender: malc@linmac.oyster.ru To: Balbir Singh cc: Ingo Molnar , linux-kernel@vger.kernel.org, Dmitry Adamushko Subject: Re: [patch] sched: accurate user accounting In-Reply-To: <4673E3D9.2020300@linux.vnet.ibm.com> Message-ID: 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> <4673E3D9.2020300@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1644 Lines: 48 On Sat, 16 Jun 2007, Balbir Singh wrote: > 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. http://www.boblycat.org/~malc/apc/cfs/ has config for 2.6.21 an the diff against 2.6.21.4-cfs-v16. I updated hog (can be found in the above directory) to call setitimer with a bit saner values (apprantly tickless has profound effect on itimers interface). While fooling around with this version of hog on 2.6.21.4-cfs-v16 i stumbled upon rather strange behavior (the screenshot is also at the address above, note that kernel was booted with maxcpus=1) [..snip..] -- vale - 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/