From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756483AbXGaJPn (ORCPT ); Tue, 31 Jul 2007 05:15:43 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753052AbXGaJPg (ORCPT ); Tue, 31 Jul 2007 05:15:36 -0400 Received: from cantor.suse.de ([195.135.220.2]:49187 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752227AbXGaJPf (ORCPT ); Tue, 31 Jul 2007 05:15:35 -0400 From: Andi Kleen To: Nick Piggin Subject: Re: [rfc] balance-on-fork NUMA placement Date: Tue, 31 Jul 2007 11:14:08 +0200 User-Agent: KMail/1.9.1 Cc: Ingo Molnar , Linux Kernel Mailing List , Linux Memory Management List References: <20070731054142.GB11306@wotan.suse.de> In-Reply-To: <20070731054142.GB11306@wotan.suse.de> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200707311114.09284.ak@suse.de> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Tuesday 31 July 2007 07:41, Nick Piggin wrote: > I haven't given this idea testing yet, but I just wanted to get some > opinions on it first. NUMA placement still isn't ideal (eg. tasks with > a memory policy will not do any placement, and process migrations of > course will leave the memory behind...), but it does give a bit more > chance for the memory controllers and interconnects to get evenly > loaded. I didn't think slab honored mempolicies by default? At least you seem to need to set special process flags. > NUMA balance-on-fork code is in a good position to allocate all of a new > process's memory on a chosen node. However, it really only starts > allocating on the correct node after the process starts running. > > task and thread structures, stack, mm_struct, vmas, page tables etc. are > all allocated on the parent's node. The page tables should be only allocated when the process runs; except for the PGD. -Andi