From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail138.messagelabs.com (mail138.messagelabs.com [216.82.249.35]) by kanga.kvack.org (Postfix) with ESMTP id A2AE66B01EF for ; Tue, 30 Mar 2010 20:39:58 -0400 (EDT) Date: Wed, 31 Mar 2010 09:34:04 +0900 From: Daisuke Nishimura Subject: Re: [PATCH(v2) -mmotm 2/2] memcg move charge of shmem at task migration Message-Id: <20100331093404.584925b3.nishimura@mxp.nes.nec.co.jp> In-Reply-To: <20100330152958.0c31b8d5.kamezawa.hiroyu@jp.fujitsu.com> References: <20100329120243.af6bfeac.nishimura@mxp.nes.nec.co.jp> <20100329120359.1c6a277d.nishimura@mxp.nes.nec.co.jp> <20100329133645.e3bde19f.kamezawa.hiroyu@jp.fujitsu.com> <20100330103301.b0d20f7e.nishimura@mxp.nes.nec.co.jp> <20100330112301.f5bb49d7.kamezawa.hiroyu@jp.fujitsu.com> <20100330114903.476af77e.nishimura@mxp.nes.nec.co.jp> <20100330121119.fcc7d45b.kamezawa.hiroyu@jp.fujitsu.com> <20100330130648.ad559645.nishimura@mxp.nes.nec.co.jp> <20100330135159.025b9366.kamezawa.hiroyu@jp.fujitsu.com> <20100330050050.GA3308@balbir.in.ibm.com> <20100330143038.422459da.nishimura@mxp.nes.nec.co.jp> <20100330144458.403b429c.kamezawa.hiroyu@jp.fujitsu.com> <20100330152958.0c31b8d5.kamezawa.hiroyu@jp.fujitsu.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org To: KAMEZAWA Hiroyuki Cc: Balbir Singh , linux-mm , Andrew Morton , Daisuke Nishimura List-ID: On Tue, 30 Mar 2010 15:29:58 +0900, KAMEZAWA Hiroyuki wrote: > On Tue, 30 Mar 2010 14:44:58 +0900 > KAMEZAWA Hiroyuki wrote: > > > On Tue, 30 Mar 2010 14:30:38 +0900 > > Daisuke Nishimura wrote: > > > > > On Tue, 30 Mar 2010 10:30:50 +0530, Balbir Singh wrote: > > > > * KAMEZAWA Hiroyuki [2010-03-30 13:51:59]: > > > > Yep, I tend to agree, but I need to take a closer look again at the > > > > patches. > > > > > > > I agree it would be more simple. I selected the current policy because > > > I was not sure whether we should move file caches(!tmpfs) with mapcount > 1, > > > and, IMHO, shared memory and file caches are different for users. > > > But it's O.K. for me to change current policy. > > > > > > > To explain what I think of, I wrote a patch onto yours. (Maybe overkill for explaination ;) > > > > Summary. > > > > + adding move_anon, move_file, move_shmem information to move_charge_struct. > > + adding hanlders for each pte types. > > + checking # of referer should be divided to each type. > > It's complicated to catch all cases in one "if" sentense. > > + FILE pages will be moved if it's charged against "from". no mapcount check. > > i.e. FILE pages should be moved even if it's not page-faulted. > > + ANON pages will be moved if it's really private. > > > > For widely shared FILE, "if it's charged against "from"" is enough good limitation. > > > > > > Hmm....how about changing meanings of new flags ? > > 1 : a charge of page caches are moved. Page cache means cache of regular files > and shared memory. But only privately mapped pages (mapcount==1) are moved. > > 2 : a charge of page caches are moved. Page cache means cache of regular files > and shared memory. They are moved even if it's shared among processes. > > When both of 1 and 2 are specified, "2" is used. Anonymous pages will not be > moved if it's shared. > > Then, total view of user interface will be simple and I think this will allow > what you want. > Thank you for your suggestion. It would be simple. I'll try in that way. Thanks, Daisuke Nishimura. -- 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