Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753692Ab0G1D0U (ORCPT ); Tue, 27 Jul 2010 23:26:20 -0400 Received: from fgwmail5.fujitsu.co.jp ([192.51.44.35]:36721 "EHLO fgwmail5.fujitsu.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752159Ab0G1D0S (ORCPT ); Tue, 27 Jul 2010 23:26:18 -0400 X-SecurityPolicyCheck-FJ: OK by FujitsuOutboundMailChecker v1.3.1 Date: Wed, 28 Jul 2010 12:21:28 +0900 From: KAMEZAWA Hiroyuki To: KAMEZAWA Hiroyuki Cc: Vivek Goyal , "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" Subject: Re: [RFC][PATCH 4/7][memcg] memcg use ID in page_cgroup Message-Id: <20100728122128.411f2128.kamezawa.hiroyu@jp.fujitsu.com> In-Reply-To: <20100728121820.0475142a.kamezawa.hiroyu@jp.fujitsu.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> <20100728121820.0475142a.kamezawa.hiroyu@jp.fujitsu.com> Organization: FUJITSU Co. LTD. X-Mailer: Sylpheed 3.0.3 (GTK+ 2.10.14; i686-pc-mingw32) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1159 Lines: 35 On Wed, 28 Jul 2010 12:18:20 +0900 KAMEZAWA Hiroyuki wrote: > > > 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.) > Sorry, one more reason. memory cgroup has much complex code for supporting move_account, re-attaching memory cgroup per pages. So, if you take care of task-move-between-groups, blkio-ID may have some problems if you only support allocation-time accounting. Thanks, -Kame -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/