From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751974AbWCRGKu (ORCPT ); Sat, 18 Mar 2006 01:10:50 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751601AbWCRGKu (ORCPT ); Sat, 18 Mar 2006 01:10:50 -0500 Received: from smtp106.mail.mud.yahoo.com ([209.191.85.216]:6235 "HELO smtp106.mail.mud.yahoo.com") by vger.kernel.org with SMTP id S1751971AbWCRGKt (ORCPT ); Sat, 18 Mar 2006 01:10:49 -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=3tqqWph6XJktQaW1je8nLBq5aI5DHadexBxlu5mtLSKu/eVt4z9m1QfVvB4JmDkmc8fabeg28SXZKzgtE9T+fDH+BUG7hILxhEuk8+iGdQpNyNwq8KSfuCq0hpXK/6m6JCOHaMkB330SX3vv493MUKYrWzN0TSXv+i4YCtB6xZg= ; Message-ID: <441BA466.6000903@yahoo.com.au> Date: Sat, 18 Mar 2006 17:10:46 +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: Andrew Morton CC: steiner@sgi.com, mingo@elte.hu, linux-kernel@vger.kernel.org Subject: Re: [PATCH] - Reduce overhead of calc_load References: <20060317145709.GA4296@sgi.com> <20060317145912.GA13207@elte.hu> <20060317152611.GA4449@sgi.com> <20060317171538.3826eb41.akpm@osdl.org> <441B6BD3.2030807@yahoo.com.au> <20060317183742.10431ba2.akpm@osdl.org> <441B7489.1090403@yahoo.com.au> <20060317211315.55457f22.akpm@osdl.org> <441B9CE2.2050204@yahoo.com.au> In-Reply-To: <441B9CE2.2050204@yahoo.com.au> 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 Nick Piggin wrote: > Andrew Morton wrote: >> Take a look at (for example) nr_iowait. We forget to spill the count out >> of the departing CPU's runqueue and hence we have to sum it across all > > > I don't think a departing runqueue should have any iowaiters on it, > should it? > No I'm wrong there. Instead of doing all these migrations and having the ugly nr_iowait and nr_uninterruptible things I would much prefer just to migrate the stat when the actual task is migrated. This should take care of cpu hotplug, and also can make everything consistent. I'll try doing a patch for that sometime. -- SUSE Labs, Novell Inc. Send instant messages to your online friends http://au.messenger.yahoo.com