From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <4354696D.4050101@jp.fujitsu.com> Date: Tue, 18 Oct 2005 12:18:05 +0900 From: KAMEZAWA Hiroyuki MIME-Version: 1.0 Subject: Re: [PATCH 0/2] Page migration via Swap V2: Overview References: <20051018004932.3191.30603.sendpatchset@schroedinger.engr.sgi.com> In-Reply-To: <20051018004932.3191.30603.sendpatchset@schroedinger.engr.sgi.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: Christoph Lameter Cc: akpm@osdl.org, linux-mm@kvack.org, ak@suse.de, lhms-devel@lists.sourceforge.net List-ID: Hi, Christoph Lameter wrote: > The disadvantage over direct page migration are: > > A. Performance: Having to go through swap is slower. > > B. The need for swap space: The area to be migrated must fit into swap. > I think migration cache will work well for A & B :) migraction cache is virtual swap, just unmap a page and modifies it as a swap cache. > C. Placement of pages at swapin is done under the memory policy in > effect at that time. This may destroy nodeset relative positioning. > How about this ? == 1. do_mbind() 2. unmap and moves to migraction cache 3. touch all pages == For 3., 2. should gather all present virtual address list... D. We need another page-cache migration functions for moving page-cache :( Moving just anon is not for memory-hotplug. (BTW, how should pages in page cache be affected by memory location control ?? I think some people discussed about that...) -- 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