From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754963Ab3AZBbR (ORCPT ); Fri, 25 Jan 2013 20:31:17 -0500 Received: from terminus.zytor.com ([198.137.202.10]:48561 "EHLO mail.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754654Ab3AZBbP (ORCPT ); Fri, 25 Jan 2013 20:31:15 -0500 Message-ID: <51033186.3000706@zytor.com> Date: Fri, 25 Jan 2013 17:29:42 -0800 From: "H. Peter Anvin" User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130110 Thunderbird/17.0.2 MIME-Version: 1.0 To: Andrew Morton CC: Tang Chen , jiang.liu@huawei.com, wujianguo@huawei.com, wency@cn.fujitsu.com, laijs@cn.fujitsu.com, linfeng@cn.fujitsu.com, yinghai@kernel.org, isimatu.yasuaki@jp.fujitsu.com, rob@landley.net, kosaki.motohiro@jp.fujitsu.com, minchan.kim@gmail.com, mgorman@suse.de, rientjes@google.com, guz.fnst@cn.fujitsu.com, rusty@rustcorp.com.au, lliubbo@gmail.com, jaegeuk.hanse@gmail.com, tony.luck@intel.com, glommer@parallels.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCH 3/3] acpi, memory-hotplug: Support getting hotplug info from SRAT. References: <1359106929-3034-1-git-send-email-tangchen@cn.fujitsu.com> <1359106929-3034-4-git-send-email-tangchen@cn.fujitsu.com> <20130125171230.34c5a273.akpm@linux-foundation.org> In-Reply-To: <20130125171230.34c5a273.akpm@linux-foundation.org> X-Enigmail-Version: 1.5 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 01/25/2013 05:12 PM, Andrew Morton wrote: > On Fri, 25 Jan 2013 17:42:09 +0800 > Tang Chen wrote: > >> NOTE: Using this way will cause NUMA performance down because the whole node >> will be set as ZONE_MOVABLE, and kernel cannot use memory on it. >> If users don't want to lose NUMA performance, just don't use it. > > I agree with this, but it means that nobody will test any of your new code. > > To get improved testing coverage, can you think of any temporary > testing-only patch which will cause testers to exercise the > memory-hotplug changes? > There is another problem: if ALL the nodes in the system support hotpluggable memory, what happens? -hpa