From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758404AbXJCMOw (ORCPT ); Wed, 3 Oct 2007 08:14:52 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755341AbXJCMOo (ORCPT ); Wed, 3 Oct 2007 08:14:44 -0400 Received: from netops-testserver-3-out.sgi.com ([192.48.171.28]:50936 "EHLO relay.sgi.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1755820AbXJCMOn (ORCPT ); Wed, 3 Oct 2007 08:14:43 -0400 Date: Wed, 3 Oct 2007 05:14:38 -0700 From: Paul Jackson To: Nick Piggin Cc: akpm@linux-foundation.org, menage@google.com, linux-kernel@vger.kernel.org, dino@in.ibm.com, cpw@sgi.com, mingo@elte.hu Subject: Re: [PATCH] cpuset and sched domains: sched_load_balance flag Message-Id: <20071003051438.e1371e99.pj@sgi.com> In-Reply-To: <200710030525.29735.nickpiggin@yahoo.com.au> References: <20070930104403.24828.48263.sendpatchset@jackhammer.engr.sgi.com> <200710030356.18090.nickpiggin@yahoo.com.au> <20071003043818.baa0e1ce.pj@sgi.com> <200710030525.29735.nickpiggin@yahoo.com.au> Organization: SGI X-Mailer: Sylpheed version 2.2.4 (GTK+ 2.8.3; i686-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org > These are what I'm worried about, and things like kswapd, pdflush, > could definitely use a huge amount of CPU. > > If you are interested in hard partitioning the system, you most > definitely want these things to be balanced across the non-isolated > CPUs. But these guys are pinned anyway (or else they would already be moved into a smaller load balanced cpuset), so why waste time load balancing what can't move? And on some of the systems I care about, we don't want to load balance these guys; rather we go to great lengths to see that they don't run at all when we don't want them to. -- I won't rest till it's the best ... Programmer, Linux Scalability Paul Jackson 1.925.600.0401