From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail202.messagelabs.com (mail202.messagelabs.com [216.82.254.227]) by kanga.kvack.org (Postfix) with SMTP id 872E96B016D for ; Wed, 13 May 2009 23:02:19 -0400 (EDT) Received: from m1.gw.fujitsu.co.jp ([10.0.50.71]) by fgwmail7.fujitsu.co.jp (Fujitsu Gateway) with ESMTP id n4E32F8b013199 for (envelope-from kamezawa.hiroyu@jp.fujitsu.com); Thu, 14 May 2009 12:02:19 +0900 Received: from smail (m1 [127.0.0.1]) by outgoing.m1.gw.fujitsu.co.jp (Postfix) with ESMTP id D22EA45DD75 for ; Thu, 14 May 2009 12:02:14 +0900 (JST) Received: from s1.gw.fujitsu.co.jp (s1.gw.fujitsu.co.jp [10.0.50.91]) by m1.gw.fujitsu.co.jp (Postfix) with ESMTP id 9D0CC45DD74 for ; Thu, 14 May 2009 12:02:14 +0900 (JST) Received: from s1.gw.fujitsu.co.jp (localhost.localdomain [127.0.0.1]) by s1.gw.fujitsu.co.jp (Postfix) with ESMTP id 916D41DB8017 for ; Thu, 14 May 2009 12:02:14 +0900 (JST) Received: from m108.s.css.fujitsu.com (m108.s.css.fujitsu.com [10.249.87.108]) by s1.gw.fujitsu.co.jp (Postfix) with ESMTP id 482411DB8013 for ; Thu, 14 May 2009 12:02:14 +0900 (JST) Date: Thu, 14 May 2009 12:00:42 +0900 From: KAMEZAWA Hiroyuki Subject: Re: [RFC] Low overhead patches for the memory resource controller Message-Id: <20090514120042.d5576d4e.kamezawa.hiroyu@jp.fujitsu.com> In-Reply-To: <20090514023930.GT13394@balbir.in.ibm.com> References: <20090513153218.GQ13394@balbir.in.ibm.com> <20090514090802.c5ac2246.kamezawa.hiroyu@jp.fujitsu.com> <20090514092405.1c3e6134.kamezawa.hiroyu@jp.fujitsu.com> <20090514023930.GT13394@balbir.in.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org To: balbir@linux.vnet.ibm.com Cc: "linux-mm@kvack.org" , Andrew Morton , "nishimura@mxp.nes.nec.co.jp" , "lizf@cn.fujitsu.com" , KOSAKI Motohiro List-ID: On Thu, 14 May 2009 08:09:30 +0530 Balbir Singh wrote: > * KAMEZAWA Hiroyuki [2009-05-14 09:24:05]: > > > On Thu, 14 May 2009 09:08:02 +0900 > > KAMEZAWA Hiroyuki wrote: > > > > > On Wed, 13 May 2009 21:02:18 +0530 > > > Balbir Singh wrote: > > > > > > > Important: Not for inclusion, for discussion only > > > > > > > > I've been experimenting with a version of the patches below. They add > > > > a PCGF_ROOT flag for tracking pages belonging to the root cgroup and > > > > disable LRU manipulation for them > > > > > > > > Caveats: > > > > > > > > 1. I've not checked accounting, accounting might be broken > > > > 2. I've not made the root cgroup as non limitable, we need to disable > > > > hard limits once we agree to go with this > > > > > > > > > > > > Tests > > > > > > > > Quick tests show an improvement with AIM9 > > > > > > > > mmotm+patch mmtom-08-may-2009 > > > > AIM9 1338.57 1338.17 > > > > Dbase 18034.16 16021.58 > > > > New Dbase 18482.24 16518.54 > > > > Shared 9935.98 8882.11 > > > > Compute 16619.81 15226.13 > > > > > > > > Comments on the approach much appreciated > > > > > > > > Feature: Remove the overhead associated with the root cgroup > > > > > > > > From: Balbir Singh > > > > > > > > This patch changes the memory cgroup and removes the overhead associated > > > > with accounting all pages in the root cgroup. As a side-effect, we can > > > > no longer set a memory hard limit in the root cgroup. > > > > > > > > A new flag is used to track page_cgroup associated with the root cgroup > > > > pages. > > > > > > Hmm ? How about ignoring memcg completely when the thread belongs to ROOT > > > cgroup rather than this halfway method ? > > > > > BTW, this will make softlimit much harder. Do you have any idea on softlimit after > > this patch ? > > > > Why would this make soft limit much harder? Since we charge up > hierarchially even now we ignore a cgroup if its soft limit is not > set. I am not sure I understand why. > I doubt I misunderstand something. Anyway, disabling soft limit to root cgroup is necessary because we have no LRU. Sorry for noise. -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