From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1762231AbXGJLj0 (ORCPT ); Tue, 10 Jul 2007 07:39:26 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754482AbXGJLjT (ORCPT ); Tue, 10 Jul 2007 07:39:19 -0400 Received: from fgwmail6.fujitsu.co.jp ([192.51.44.36]:36156 "EHLO fgwmail6.fujitsu.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751577AbXGJLjS (ORCPT ); Tue, 10 Jul 2007 07:39:18 -0400 Date: Tue, 10 Jul 2007 20:38:48 +0900 From: KAMEZAWA Hiroyuki To: mel@skynet.ie (Mel Gorman) Cc: Andrew Morton , npiggin@suse.de, kenchen@google.com, jschopp@austin.ibm.com, apw@shadowen.org, a.p.zijlstra@chello.nl, y-goto@jp.fujitsu.com, clameter@sgi.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: -mm merge plans -- anti-fragmentation Message-Id: <20070710203848.e7bbc98e.kamezawa.hiroyu@jp.fujitsu.com> In-Reply-To: <20070710111202.GC25512@skynet.ie> References: <20070710102043.GA20303@skynet.ie> <20070710200115.b5bbfb4a.kamezawa.hiroyu@jp.fujitsu.com> <20070710111202.GC25512@skynet.ie> Organization: Fujitsu X-Mailer: Sylpheed 2.4.2 (GTK+ 2.10.11; i686-pc-mingw32) 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 On Tue, 10 Jul 2007 12:12:02 +0100 mel@skynet.ie (Mel Gorman) wrote: > > For (2), we need some method for specifing the range we will remove. For doing that, > > ZONE seems to be good candidate. Now we use "kernelcore=" boot option to create > > ZONE_MOVABLE by hand. > > At the risk of putting you on the spot, do you mind saying whether the > grouping pages by mobility and ZONE_MOVABLE patches are going in the > direction you want or should something totally different be done? If > they are going the right direction, is there anything critical that is > missing right now? > "grouping pages by mobility and ZONE_MOVABLE" things are what I want. And I want to go with them. But I know some people doesn't want to increase # of zones. It is my concern. I know ZONE_MOVABLE works well but there are people who don't want new zone. So making ZONE_MOVABLE as configurable will be good thing, as Nick Piggin pointed. About my other concerns , see node hotplug (below). > > But this is the first step. I know Intel guy posted > > his idea to specify Hotpluggable-Memory range in SRAT (by firmware). > > There may be additional work required to make this play nicely with > ZONE_MOVABLE but it shouldn't be anything fundamental. > yes. And I don't know his idea about SRAT is acceped in firmware comunity or not. For now, kernelcore= works enough for memory hotplug. > > And I think that > > other method may be introduced for node-hotplug. > > > > Same as above really. If the node contains one zone - ZONE_MOVABLE, it > would work for unplugging. > Our concern on node hotplug is "bootmem" and hashtable , pgdata, memmap etc.... NUMA initilization (of each arch) includes something complicated. But this is not directly related to ZONE_MOVABLE things I think. It's node-hotplug problem. We are now consdiering hot-add nodes after initcalls(). -Kame