Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751232AbWB0M2W (ORCPT ); Mon, 27 Feb 2006 07:28:22 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751818AbWB0M2W (ORCPT ); Mon, 27 Feb 2006 07:28:22 -0500 Received: from smtp102.mail.mud.yahoo.com ([209.191.85.212]:28849 "HELO smtp102.mail.mud.yahoo.com") by vger.kernel.org with SMTP id S1751232AbWB0M2V (ORCPT ); Mon, 27 Feb 2006 07:28:21 -0500 DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=s1024; d=yahoo.com.au; h=Received:Message-ID:Date:From:User-Agent:X-Accept-Language:MIME-Version:To:CC:Subject:References:In-Reply-To:Content-Type:Content-Transfer-Encoding; b=D0++mDswJgECGX7mN5CQcGwSAV3aBXprz0Yy+t+0CAHPDq3xA7Wnb36ft+vc9b/xQXiuZcYwSXuZbQ1Ra1yPMQHLCvmvaFPaDpLW/yUKctynyeoUE3U9M4gmJv00+wf6SaM7pgX7DuSUNMA1e6ra8uJVVFFg93HBfuF11Udx28M= ; Message-ID: <4402F065.3010303@yahoo.com.au> Date: Mon, 27 Feb 2006 23:28:21 +1100 From: Nick Piggin User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.7.12) Gecko/20051007 Debian/1.7.12-1 X-Accept-Language: en MIME-Version: 1.0 To: Shailabh Nagar CC: linux-kernel , lse-tech Subject: Re: [Patch 2/7] Add sysctl for schedstats References: <1141026996.5785.38.camel@elinux04.optonline.net> <1141027367.5785.42.camel@elinux04.optonline.net> <1141027923.5785.50.camel@elinux04.optonline.net> <4402C3BB.7010705@yahoo.com.au> <4402C954.2080606@watson.ibm.com> In-Reply-To: <4402C954.2080606@watson.ibm.com> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1140 Lines: 32 Shailabh Nagar wrote: > Nick Piggin wrote: >> >> And clearing this at all is not really needed for the schedstats >> interface. >> You have a timestamp and a set of accumulated values, so it is easy to >> work >> out deltas. So do you need this? > > > Not clearing the stats will mean userspace has to distinguish between > the tasks > that are hanging around from before the last turn off, and the ones > created after > wards. Any delta taken across an interval where schedstats was turned > off will > give the impression a task was sleeping during the interval (and hence > show it had > a lesser average wait time than it might actually have experienced). Presumably a delta taken acrsoss an interval where schedstats was turned off would be rather inaccurate, no matter what. -- SUSE Labs, Novell Inc. Send instant messages to your online friends http://au.messenger.yahoo.com - 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/