From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2992540AbWJTRuJ (ORCPT ); Fri, 20 Oct 2006 13:50:09 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S2992550AbWJTRuJ (ORCPT ); Fri, 20 Oct 2006 13:50:09 -0400 Received: from mga05.intel.com ([192.55.52.89]:4682 "EHLO fmsmga101.fm.intel.com") by vger.kernel.org with ESMTP id S2992540AbWJTRuH (ORCPT ); Fri, 20 Oct 2006 13:50:07 -0400 X-ExtLoop1: 1 X-IronPort-AV: i="4.09,336,1157353200"; d="scan'208"; a="149595374:sNHT2229258906" Date: Fri, 20 Oct 2006 10:29:46 -0700 From: "Siddha, Suresh B" To: Nick Piggin Cc: Martin Bligh , Paul Jackson , akpm@osdl.org, menage@google.com, Simon.Derr@bull.net, linux-kernel@vger.kernel.org, dino@in.ibm.com, rohitseth@google.com, holt@sgi.com, dipankar@in.ibm.com, suresh.b.siddha@intel.com Subject: Re: [RFC] cpuset: remove sched domain hooks from cpusets Message-ID: <20061020102946.A8481@unix-os.sc.intel.com> References: <20061019092358.17547.51425.sendpatchset@sam.engr.sgi.com> <4537527B.5050401@yahoo.com.au> <20061019120358.6d302ae9.pj@sgi.com> <4537D056.9080108@yahoo.com.au> <4537D6E8.8020501@google.com> <4538F34A.7070703@yahoo.com.au> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.2.5.1i In-Reply-To: <4538F34A.7070703@yahoo.com.au>; from nickpiggin@yahoo.com.au on Sat, Oct 21, 2006 at 02:03:22AM +1000 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Sat, Oct 21, 2006 at 02:03:22AM +1000, Nick Piggin wrote: > Martin Bligh wrote: > > We (Google) are planning to use it to do some partitioning, albeit on > > much smaller machines. I'd really like to NOT use cpus_allowed from > > previous experience - if we can get it to to partition using separated > > sched domains, that would be much better. > > > > From my dim recollections of previous discussions when cpusets was > > added in the first place, we asked for exactly the same thing then. > > I think some of the problem came from the fact that "exclusive" > > to cpusets doesn't actually mean exclusive at all, and they're > > shared in some fashion. Perhaps that issue is cleared up now? > > /me crosses all fingers and toes and prays really hard. > > The I believe, is that an exclusive cpuset can have an exclusive parent > and exclusive children, which obviously all overlap one another, and > thus you have to do the partition only at the top-most exclusive cpuset. > > Currently, cpusets is creating partitions in cpus_exclusive children as > well, which breaks balancing for the parent. > > The patch I posted previously should (modulo bugs) only do partitioning > in the top-most cpuset. I still need clarification from Paul as to why > this is unacceptable, though. I like the direction of Nick's patch which do domain partitioning at the top-most exclusive cpuset. thanks, suresh