From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262304AbUCIXOE (ORCPT ); Tue, 9 Mar 2004 18:14:04 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262408AbUCIXOE (ORCPT ); Tue, 9 Mar 2004 18:14:04 -0500 Received: from alt.aurema.com ([203.217.18.57]:16008 "EHLO smtp.sw.oz.au") by vger.kernel.org with ESMTP id S262304AbUCIXN6 (ORCPT ); Tue, 9 Mar 2004 18:13:58 -0500 Date: Wed, 10 Mar 2004 10:13:47 +1100 From: Kingsley Cheung To: Andrew Morton , linux-kernel@vger.kernel.org Subject: Re: [PATCH] For preventing kstat overflow Message-ID: <20040310101347.B30341@aurema.com> Mail-Followup-To: Andrew Morton , linux-kernel@vger.kernel.org References: <20040309132338.A30341@aurema.com> <20040308185354.70040c8b.akpm@osdl.org> <20040309165704.L29788@aurema.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: <20040309165704.L29788@aurema.com>; from kingsley@aurema.com on Tue, Mar 09, 2004 at 04:57:04PM +1100 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Mar 09, 2004 at 04:57:04PM +1100, Kingsley Cheung wrote: > On Mon, Mar 08, 2004 at 06:53:54PM -0800, Andrew Morton wrote: > > Kingsley Cheung wrote: > > > > > > Hi All, > > > > > > What do people think of a patch to change the fields in cpu_usage_stat > > > from unsigned ints to unsigned long longs? And the same change for > > > nr_switches in the runqueue structure too? > > > > Sounds unavoidable. > > > > > Its actually worse for context > > > switches on a busy system, for we've been seeing an average of ten > > > switches a tick for some of the statistics we have. > > > > Sounds broken. What CPU scheduler are you using? > > Um, what do you mean by broken? > > Well, as for the scheduler, its the Entitlement Based Scheduler, but > it doesn't look like its got anything to do with the scheduler. Some > work loads we have been testing just have processes that come and go > so frequently that the context switch rate is high. Even when Ingo > posted his original O(1) patch (see > http://marc.theaimsgroup.com/?l=linux-kernel&m=101010394225604&w=2) he > claimed high context switch rates. Oh, just in case there's some confusion... even though we've been seeing it for EBS, the patch is for 2.6.3. -- Kingsley