From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S263602AbUC3LUL (ORCPT ); Tue, 30 Mar 2004 06:20:11 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S263612AbUC3LUL (ORCPT ); Tue, 30 Mar 2004 06:20:11 -0500 Received: from ecbull20.frec.bull.fr ([129.183.4.3]:46996 "EHLO ecbull20.frec.bull.fr") by vger.kernel.org with ESMTP id S263602AbUC3LUC (ORCPT ); Tue, 30 Mar 2004 06:20:02 -0500 Message-ID: <40695802.1F13AB0D@nospam.org> Date: Tue, 30 Mar 2004 13:20:34 +0200 From: Zoltan Menyhart Reply-To: Zoltan.Menyhart@bull.net Organization: Bull S.A. X-Mailer: Mozilla 4.78 [en] (X11; U; AIX 4.3) X-Accept-Language: fr, en MIME-Version: 1.0 To: Hirokazu Takahashi CC: haveblue@us.ibm.com, linux-ia64@vger.kernel.org, linux-kernel@vger.kernel.org, iwamoto@valinux.co.jp Subject: Re: Migrate pages from a ccNUMA node to another - patch References: <4063F581.ACC5C511@nospam.org> <1080321646.31638.105.camel@nighthawk> <20040330082741.541B77054E@sv1.valinux.co.jp> <20040330.180523.08003015.taka@valinux.co.jp> Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Hirokazu Takahashi wrote: > > Hello, > > > > Have you considered any common ground your patch might share with the > > > people doing memory hotplug? > > > > > > http://people.valinux.co.jp/~iwamoto/mh.html > > > > > > They have a similar problem to your migration that occurs when a user > > > wants to remove a whole or partial NUMA node. > > > lhms-devel@lists.sourceforge.net > > > > Processes must be migrated to other nodes when a node is being > > removed. Conversely, processes may be migrated from other nodes when > > a node is added. I'm not familiar with NUMA things, and I think our > > team doesn't have a particular solution. If you have some idea, > > that's great. > > > > BTW, it seems page migration can use my remap_onepage function. Our > > code can move most kinds of pages including hugetlbfs pages and page > > caches. > > I believe his patch will interest you since most of the code is > independent of cpu architecture and it also covers mmaped files, > shmem, ramdisk, mlocked pages and so on. > > We will post new version of the memory hotplug patches in a week. > > Thank you, > Hirokazu Takahashi. I am afraid the "remap_onepage()" function + the modifications necessary at some other places are too much for me :-) You do a couple of retries, waits. I cannot afford spending so much as overhead due to some performance optimization. I can understand that if you want to remove a node / memory module, then you have to succeed by all means, you have to handle all kinds of pages, the performance is not at a premium. Regards, Zoltán Menyhárt