From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752811AbZHaMXT (ORCPT ); Mon, 31 Aug 2009 08:23:19 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752530AbZHaMXS (ORCPT ); Mon, 31 Aug 2009 08:23:18 -0400 Received: from e23smtp04.au.ibm.com ([202.81.31.146]:41649 "EHLO e23smtp04.au.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752424AbZHaMXS (ORCPT ); Mon, 31 Aug 2009 08:23:18 -0400 Date: Mon, 31 Aug 2009 17:53:16 +0530 From: Balbir Singh To: KAMEZAWA Hiroyuki Cc: "linux-mm@kvack.org" , "linux-kernel@vger.kernel.org" , "nishimura@mxp.nes.nec.co.jp" Subject: Re: [RFC][PATCH 2/5] memcg: uncharge in batched manner Message-ID: <20090831122316.GM4770@balbir.in.ibm.com> Reply-To: balbir@linux.vnet.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> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline In-Reply-To: <48d928bed22f20fc495e9ca1758dc7ed.squirrel@webmail-b.css.fujitsu.com> User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org * 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? cond_resched() is bad in this case.. since it means we'll stay longer before we release the cgroup. -- Balbir