From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Mon, 12 Nov 2007 09:50:00 +0900 From: KAMEZAWA Hiroyuki Subject: Re: about page migration on UMA Message-Id: <20071112095000.48aaed78.kamezawa.hiroyu@jp.fujitsu.com> In-Reply-To: <1194643851.7078.112.camel@localhost> References: <20071016191949.cd50f12f.kamezawa.hiroyu@jp.fujitsu.com> <20071016192341.1c3746df.kamezawa.hiroyu@jp.fujitsu.com> <20071017141609.0eb60539.kamezawa.hiroyu@jp.fujitsu.com> <20071017145009.e4a56c0d.kamezawa.hiroyu@jp.fujitsu.com> <02f001c8108c$a3818760$3708a8c0@arcapub.arca.com> <6934efce0711091131n1acd2ce1h7bb17f9f3cb0f235@mail.gmail.com> <6934efce0711091154x74fe4405q5a9e291b3d9780f0@mail.gmail.com> <1194643851.7078.112.camel@localhost> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: Dave Hansen Cc: Christoph Lameter , Jared Hulbert , "Jacky(GuangXiang Lee)" , linux-mm@kvack.org, Yasunori Goto List-ID: On Fri, 09 Nov 2007 13:30:50 -0800 Dave Hansen wrote: > On Fri, 2007-11-09 at 11:58 -0800, Christoph Lameter wrote: > > Well one idea is to generate a sysfs file that can take a physical memory > > range? echo the range to the sysfs file. The kernel can then try to > > vacate the memory range. > > When memory hotplug is on, you should see memory broken up into > "sections", and exported in sysfs today: > > /sys/devices/system/memory > > You can on/offline memory from there, and it should be pretty easy to > figure out the physical addresses with the phys_index file. > yes. Using current memory-hotplug interface is the easiest way. What you have to do in your arch is... 1. support SPARSEMEM and define SECTION_SIZE to be suitable 2. add Memory Hotplug config. see mm/Kconfig 3. use ZONE_MOVABLE with boot option. 4. maybe you have to find that you have to define your own walk_memory_resource() or not. Maybe reading Badari's patches in these days for ppc64 support will help you. Contiguous memory-size memory can be offlined. One problem I don't understand is memory hotplug cannot be used if CONFIG_HIBERNATION is on. If this is problem to you, you may need some work. Regards, -Kame -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org