From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Wed, 11 Jun 2008 13:14:37 +0900 From: KAMEZAWA Hiroyuki Subject: Re: [RFD][PATCH] memcg: Move Usage at Task Move Message-Id: <20080611131437.76961fc3.kamezawa.hiroyu@jp.fujitsu.com> In-Reply-To: <20080611034446.4C5535A23@siro.lan> References: <20080611122500.677757c6.kamezawa.hiroyu@jp.fujitsu.com> <20080611034446.4C5535A23@siro.lan> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: YAMAMOTO Takashi Cc: nishimura@mxp.nes.nec.co.jp, linux-mm@kvack.org, containers@lists.osdl.org, menage@google.com, balbir@linux.vnet.ibm.com, xemul@openvz.org List-ID: On Wed, 11 Jun 2008 12:44:46 +0900 (JST) yamamoto@valinux.co.jp (YAMAMOTO Takashi) wrote: > > I'm now considering following logic. How do you think ? > > > > Assume: move TASK from group:CURR to group:DEST. > > > > == move_task(TASK, CURR, DEST) > > > > if (DEST's limit is unlimited) > > moving TASK > > return success. > > > > usage = check_usage_of_task(TASK). > > > > /* try to reserve enough room in destionation */ > > if (try_to_reserve_enough_room(DEST, usage)) { > > move TASK to DEST and move pages AMAP. > > /* usage_of_task(TASK) can be changed while we do this. > > Then, we move AMAP. */ > > return success; > > } > > return failure. > > == > > AMAP means that you might leave some random charges in CURR? > yes. but we can reduce bad case by some way - reserve more than necessary. or - read_lock mm->sem while move. > i think that you can redirect new charges in TASK to DEST > so that usage_of_task(TASK) will not grow. > Hmm, to do that, we have to handle complicated cgroup's attach ops. at this moving, memcg is pointed by - TASK->cgroup->memcg(CURR) after move - TASK->another_cgroup->memcg(DEST) This move happens before cgroup is replaced by another_cgroup. 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