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 ESMTP id 1AFE66B01D3 for ; Tue, 8 Jun 2010 22:13:13 -0400 (EDT) Date: Wed, 9 Jun 2010 11:05:35 +0900 From: Daisuke Nishimura Subject: Re: [RFC][PATCH] memcg remove css_get/put per pages Message-Id: <20100609110535.8005ef04.nishimura@mxp.nes.nec.co.jp> In-Reply-To: <20100609095448.1f020a22.kamezawa.hiroyu@jp.fujitsu.com> References: <20100608121901.3cab9bdf.kamezawa.hiroyu@jp.fujitsu.com> <20100608163129.9297f3aa.nishimura@mxp.nes.nec.co.jp> <20100609095448.1f020a22.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: "linux-mm@kvack.org" , "balbir@linux.vnet.ibm.com" , Daisuke Nishimura List-ID: On Wed, 9 Jun 2010 09:54:48 +0900, KAMEZAWA Hiroyuki wrote: > On Tue, 8 Jun 2010 16:31:29 +0900 > Daisuke Nishimura wrote: > > > On Tue, 8 Jun 2010 12:19:01 +0900, KAMEZAWA Hiroyuki wrote: (snip) > > > 1. Because css_get/put calls atoimic_inc()/dec, heavy call of them > > > on large smp will not scale well. > > I'm sorry if I'm asking a stupid question, the number of css_get/put > > would be: > > > > before: > > get:1 in charge > > put:1 in uncharge > > after: > > get:1, put:1 in charge > > no get/put in uncharge > > > > right ? > > No. > > before: get 1 in charge. > put 1 at charge > > after: > no get at charge in fast path (cunsume_stcok hits.) > get 1 at accssing res_counter and reclaim, put 1 after it. > no get/put in uncharge. > > > Then, isn't there any change as a whole ? > > > We get much benefit when consume_stock() works. > Ah, I missed comsume_stock(). The number of get/put would be decreased very much. Thank you for your explanation. 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