From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932131Ab0FAPsS (ORCPT ); Tue, 1 Jun 2010 11:48:18 -0400 Received: from one.firstfloor.org ([213.235.205.2]:33452 "EHLO one.firstfloor.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757078Ab0FAPsR (ORCPT ); Tue, 1 Jun 2010 11:48:17 -0400 To: Nick Piggin Cc: Linus Torvalds , Ingo Molnar , Peter Zijlstra , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Lee@firstfloor.org, Schermerh@firstfloor.org Subject: Re: [rfc] forked kernel task and mm structures imbalanced on NUMA From: Andi Kleen References: <20100601073343.GQ9453@laptop> Date: Tue, 01 Jun 2010 17:48:10 +0200 In-Reply-To: <20100601073343.GQ9453@laptop> (Nick Piggin's message of "Tue\, 1 Jun 2010 17\:33\:43 +1000") Message-ID: <87wruiycsl.fsf@basil.nowhere.org> User-Agent: Gnus/5.11 (Gnus v5.11) Emacs/22.3 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Nick Piggin writes: > This isn't really a new problem, and I don't know how important it is, > but I recently came across it again when doing some aim7 testing with > huge numbers of tasks. Seems reasonable. Of course you need to at least save/restore the old CPU policy, and use a subset of it. Another approach would be to migrate this on touch, but that is probably slightly more difficult. The advantage would be that on multiple migrations it would follow. And it would be a bit slower for the initial case. -Andi -- ak@linux.intel.com -- Speaking for myself only.