From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261331AbVFBVEj (ORCPT ); Thu, 2 Jun 2005 17:04:39 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261306AbVFBVDG (ORCPT ); Thu, 2 Jun 2005 17:03:06 -0400 Received: from e31.co.us.ibm.com ([32.97.110.129]:31460 "EHLO e31.co.us.ibm.com") by vger.kernel.org with ESMTP id S261280AbVFBULA (ORCPT ); Thu, 2 Jun 2005 16:11:00 -0400 Message-ID: <429F67C4.9060506@austin.ibm.com> Date: Thu, 02 Jun 2005 15:10:44 -0500 From: Joel Schopp Reply-To: jschopp@austin.ibm.com User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.7.3) Gecko/20040910 X-Accept-Language: en-us, en MIME-Version: 1.0 To: Ray Bryant CC: Nick Piggin , "Martin J. Bligh" , Mel Gorman , linux-mm@kvack.org, linux-kernel@vger.kernel.org, akpm@osdl.org Subject: Re: Avoiding external fragmentation with a placement policy Version 12 References: <20050531112048.D2511E57A@skynet.csn.ul.ie> <429E20B6.2000907@austin.ibm.com> <429E4023.2010308@yahoo.com.au> <423970000.1117668514@flay> <429E483D.8010106@yahoo.com.au> <434510000.1117670555@flay> <429E50B8.1060405@yahoo.com.au> <429F2B26.9070509@austin.ibm.com> <429F631E.6020401@engr.sgi.com> In-Reply-To: <429F631E.6020401@engr.sgi.com> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org > Could someone point me at the "Page migration defrag" patch, or > describe what this is. Does this depend on the page migration > patches from memory hotplug to move pages or is it something > different? I don't think anybody has actually written such a patch yet (correct me if I'm wrong). When somebody does it will certainly depend on the page migration patches. As far as describing what it is, the concept is pretty simple. Migrate in use pieces of memory around to make lots of smaller unallocated memory into fewer larger unallocated memory.