From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1161717AbXEBHZl (ORCPT ); Wed, 2 May 2007 03:25:41 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1161746AbXEBHZl (ORCPT ); Wed, 2 May 2007 03:25:41 -0400 Received: from netops-testserver-3-out.sgi.com ([192.48.171.28]:47205 "EHLO relay.sgi.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1161717AbXEBHZk (ORCPT ); Wed, 2 May 2007 03:25:40 -0400 Date: Wed, 2 May 2007 00:25:38 -0700 From: Paul Jackson To: "Paul Menage" Cc: rientjes@google.com, torvalds@linux-foundation.org, clameter@cthulhu.engr.sgi.com, linux-kernel@vger.kernel.org Subject: Re: [patch] cpusets: allow empty {cpus,mems}_allowed to be set for unpopulated cpuset Message-Id: <20070502002538.a863bf95.pj@sgi.com> In-Reply-To: <6599ad830705012036g21cc8470nff246e146b1e4023@mail.gmail.com> References: <20070501202201.6903d922.pj@sgi.com> <6599ad830705012036g21cc8470nff246e146b1e4023@mail.gmail.com> 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 Paul M wrote: > Otherwise the only way to reclaim > the node for a different sibling is to delete the cpuset. Ah - I just made sense of that sentence. It means that if a particular memory node is in one cpuset, and you'd like to have it in another cpuset instead, then with the existing kernel code, you had to special case the situation where this memory node was the last node in the original cpuset - deleting the cpuset just to do this. Yeah - I have never given much thought to moving memory nodes from one cpuset to another. No good reason; it just didn't happen to be a common operation for the uses of cpusets I cared about. I still have this niggling fear that there was something that passed my view, years ago, that this proposed change (to allow unpopulating a cpuset) will break. But I'll be damned if I can remember what it was. Ok ... if this patch passes my cpuset_test (guess I'll try that now) then I'm ok with this patch. -- I won't rest till it's the best ... Programmer, Linux Scalability Paul Jackson 1.925.600.0401