From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail172.messagelabs.com (mail172.messagelabs.com [216.82.254.3]) by kanga.kvack.org (Postfix) with SMTP id 3490D6B024D for ; Tue, 27 Jul 2010 23:23:12 -0400 (EDT) Received: from m5.gw.fujitsu.co.jp ([10.0.50.75]) by fgwmail5.fujitsu.co.jp (Fujitsu Gateway) with ESMTP id o6S3N9bt008817 for (envelope-from kamezawa.hiroyu@jp.fujitsu.com); Wed, 28 Jul 2010 12:23:10 +0900 Received: from smail (m5 [127.0.0.1]) by outgoing.m5.gw.fujitsu.co.jp (Postfix) with ESMTP id DF8E445DE54 for ; Wed, 28 Jul 2010 12:23:08 +0900 (JST) Received: from s5.gw.fujitsu.co.jp (s5.gw.fujitsu.co.jp [10.0.50.95]) by m5.gw.fujitsu.co.jp (Postfix) with ESMTP id BF86845DE52 for ; Wed, 28 Jul 2010 12:23:08 +0900 (JST) Received: from s5.gw.fujitsu.co.jp (localhost.localdomain [127.0.0.1]) by s5.gw.fujitsu.co.jp (Postfix) with ESMTP id 96192E08004 for ; Wed, 28 Jul 2010 12:23:08 +0900 (JST) Received: from m108.s.css.fujitsu.com (m108.s.css.fujitsu.com [10.249.87.108]) by s5.gw.fujitsu.co.jp (Postfix) with ESMTP id 4A741E18001 for ; Wed, 28 Jul 2010 12:23:08 +0900 (JST) Date: Wed, 28 Jul 2010 12:18:20 +0900 From: KAMEZAWA Hiroyuki Subject: Re: [RFC][PATCH 4/7][memcg] memcg use ID in page_cgroup Message-Id: <20100728121820.0475142a.kamezawa.hiroyu@jp.fujitsu.com> In-Reply-To: <20100728031358.GG12642@redhat.com> References: <20100727165155.8b458b7f.kamezawa.hiroyu@jp.fujitsu.com> <20100727165629.6f98145c.kamezawa.hiroyu@jp.fujitsu.com> <20100728023904.GE12642@redhat.com> <20100728114402.571b8ec6.kamezawa.hiroyu@jp.fujitsu.com> <20100728031358.GG12642@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org To: Vivek Goyal Cc: "linux-mm@kvack.org" , "nishimura@mxp.nes.nec.co.jp" , "balbir@linux.vnet.ibm.com" , gthelen@google.com, m-ikeda@ds.jp.nec.com, "akpm@linux-foundation.org" , "linux-kernel@vger.kernel.org" List-ID: On Tue, 27 Jul 2010 23:13:58 -0400 Vivek Goyal wrote: > > > So the idea is that when a page is allocated, also store the blk_group > > > id and once that page is submitted for writeback, we should be able > > > to associate it to right blkio group? > > > > > blk_cgroup id can be attached whenever you wants. please overwrite > > page_cgroup->blk_cgroup when it's necessary. > > > Did you read Ikeda's patch ? I myself doesn't have patches at this point. > > This is just for make a room for recording blkio-ID, which was requested > > for a year. > > I have not read his patches yet. IIRC, previously there were issues > regarding which group should be charged for the page. The person who > allocated it or the thread which did last write to it etc... I guess > we can sort that out later. > > > > > Hmm, but page-allocation-time doesn't sound very good for me. > > > > Why? > As you wrote, by attaching ID when a page cache is added, we'll have much chances of free-rider until it's paged out. So, adding some reseting-owner point may be good. But considering real world usage, I may be wrong. There will not be much free rider in real world, especially at write(). Then, page-allocation time may be good. (Because database doesn't use page-cache, there will be no big random write application.) Thanks, -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