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 495B16B005D for ; Mon, 31 Aug 2009 10:36:14 -0400 (EDT) Received: from m5.gw.fujitsu.co.jp ([10.0.50.75]) by fgwmail5.fujitsu.co.jp (Fujitsu Gateway) with ESMTP id n7VEaETY005631 for (envelope-from kamezawa.hiroyu@jp.fujitsu.com); Mon, 31 Aug 2009 23:36:14 +0900 Received: from smail (m5 [127.0.0.1]) by outgoing.m5.gw.fujitsu.co.jp (Postfix) with ESMTP id CE77A45DE4E for ; Mon, 31 Aug 2009 23:36:13 +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 A6C1645DE4F for ; Mon, 31 Aug 2009 23:36:13 +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 7E745E1800A for ; Mon, 31 Aug 2009 23:36:13 +0900 (JST) Received: from ml13.s.css.fujitsu.com (ml13.s.css.fujitsu.com [10.249.87.103]) by s5.gw.fujitsu.co.jp (Postfix) with ESMTP id 38AFF1DB803C for ; Mon, 31 Aug 2009 23:36:13 +0900 (JST) Message-ID: <641cca8561405679780a7afa4442e2a5.squirrel@webmail-b.css.fujitsu.com> In-Reply-To: <20090831122316.GM4770@balbir.in.ibm.com> References: <20090828132015.10a42e40.kamezawa.hiroyu@jp.fujitsu.com> <20090828132438.b33828bc.kamezawa.hiroyu@jp.fujitsu.com> <20090831110204.GG4770@balbir.in.ibm.com> <119e8331d1210b1f56d0f6416863bfbc.squirrel@webmail-b.css.fujitsu.com> <20090831121008.GL4770@balbir.in.ibm.com> <48d928bed22f20fc495e9ca1758dc7ed.squirrel@webmail-b.css.fujitsu.com> <20090831122316.GM4770@balbir.in.ibm.com> Date: Mon, 31 Aug 2009 23:36:12 +0900 (JST) Subject: Re: [RFC][PATCH 2/5] memcg: uncharge in batched manner From: "KAMEZAWA Hiroyuki" MIME-Version: 1.0 Content-Type: text/plain;charset=iso-2022-jp Content-Transfer-Encoding: 8bit Sender: owner-linux-mm@kvack.org To: balbir@linux.vnet.ibm.com Cc: KAMEZAWA Hiroyuki , "linux-mm@kvack.org" , "linux-kernel@vger.kernel.org" , "nishimura@mxp.nes.nec.co.jp" List-ID: Balbir Singh wrote: > * KAMEZAWA Hiroyuki [2009-08-31 > 21:14:10]: > >> Balbir Singh wrote: >> >> > Does this effect deleting of a group and delay it by a large >> amount? >> >> > >> >> plz see what cgroup_release_and_xxxx fixed. This is not for delay >> >> but for race-condition, which makes rmdir sleep permanently. >> >> >> > >> > I've seen those patches, where rmdir() can hang. My conern was time >> > elapsed since we do css_get() and do a cgroup_release_and_wake_rmdir() >> > >> plz read unmap() and truncate() code. >> The number of pages handled without cond_resched() is limited. >> >> > > I understand that part, I was referring to tasks stuck doing rmdir() > while we do batched uncharge, will it be very visible to the end user? truncate/invalidate etc...is done in chunk of pagevec size. Now, it's 14. then, batched uncharge is done per 14 pages, IIUC. > cond_resched() is bad in this case.. since it means we'll stay longer > before we release the cgroup. cond_resched() is caller's matter. Not related memcg because we dont't call it. Thanks, -Kame > > > -- > Balbir > -- 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