From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail6.bemta12.messagelabs.com (mail6.bemta12.messagelabs.com [216.82.250.247]) by kanga.kvack.org (Postfix) with ESMTP id 83C748D003B for ; Tue, 17 May 2011 20:07:36 -0400 (EDT) Received: from m3.gw.fujitsu.co.jp (unknown [10.0.50.73]) by fgwmail6.fujitsu.co.jp (Postfix) with ESMTP id 669913EE0BD for ; Wed, 18 May 2011 09:07:33 +0900 (JST) Received: from smail (m3 [127.0.0.1]) by outgoing.m3.gw.fujitsu.co.jp (Postfix) with ESMTP id 48CDF45DE92 for ; Wed, 18 May 2011 09:07:33 +0900 (JST) Received: from s3.gw.fujitsu.co.jp (s3.gw.fujitsu.co.jp [10.0.50.93]) by m3.gw.fujitsu.co.jp (Postfix) with ESMTP id 13D6745DE93 for ; Wed, 18 May 2011 09:07:33 +0900 (JST) Received: from s3.gw.fujitsu.co.jp (localhost.localdomain [127.0.0.1]) by s3.gw.fujitsu.co.jp (Postfix) with ESMTP id 035961DB8040 for ; Wed, 18 May 2011 09:07:33 +0900 (JST) Received: from m105.s.css.fujitsu.com (m105.s.css.fujitsu.com [10.240.81.145]) by s3.gw.fujitsu.co.jp (Postfix) with ESMTP id AD8F51DB8038 for ; Wed, 18 May 2011 09:07:32 +0900 (JST) Date: Wed, 18 May 2011 09:00:47 +0900 From: KAMEZAWA Hiroyuki Subject: Re: [PATCH] memcg: fix typo in the soft_limit stats. Message-Id: <20110518090047.0b46a60d.kamezawa.hiroyu@jp.fujitsu.com> In-Reply-To: <20110518084919.988d3d41.kamezawa.hiroyu@jp.fujitsu.com> References: <1305583230-2111-1-git-send-email-yinghan@google.com> <20110516231512.GW16531@cmpxchg.org> <20110516171820.124a8fbc.akpm@linux-foundation.org> <20110518084919.988d3d41.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 List-ID: To: KAMEZAWA Hiroyuki Cc: Andrew Morton , Ying Han , Johannes Weiner , KOSAKI Motohiro , Minchan Kim , Daisuke Nishimura , Balbir Singh , Tejun Heo , Pavel Emelyanov , Li Zefan , Mel Gorman , Christoph Lameter , Rik van Riel , Hugh Dickins , Michal Hocko , Dave Hansen , Zhu Yanhai , linux-mm@kvack.org On Wed, 18 May 2011 08:49:19 +0900 KAMEZAWA Hiroyuki wrote: > On Mon, 16 May 2011 17:18:20 -0700 > Andrew Morton wrote: > > > On Mon, 16 May 2011 17:05:02 -0700 > > Ying Han wrote: > > > > > On Mon, May 16, 2011 at 4:15 PM, Johannes Weiner wrote: > > > > > > > On Mon, May 16, 2011 at 03:00:30PM -0700, Ying Han wrote: > > > > > This fixes the typo in the memory.stat including the following two > > > > > stats: > > > > > > > > > > $ cat /dev/cgroup/memory/A/memory.stat > > > > > total_soft_steal 0 > > > > > total_soft_scan 0 > > > > > > > > > > And change it to: > > > > > > > > > > $ cat /dev/cgroup/memory/A/memory.stat > > > > > total_soft_kswapd_steal 0 > > > > > total_soft_kswapd_scan 0 > > > > > > > > > > Signed-off-by: Ying Han > > > > > > > > I am currently proposing and working on a scheme that makes the soft > > > > limit not only a factor for global memory pressure, but for > > > > hierarchical reclaim in general, to prefer child memcgs during reclaim > > > > that are in excess of their soft limit. > > > > > > > > Because this means prioritizing memcgs over one another, rather than > > > > having explicit soft limit reclaim runs, there is no natural counter > > > > for pages reclaimed due to the soft limit anymore. > > > > > > > > Thus, for the patch that introduces this counter: > > > > > > > > Nacked-by: Johannes Weiner > > > > > > > > > > This patch is fixing a typo of the stats being integrated into mmotm. Does > > > it make sense to fix the > > > existing stats first while we are discussing other approaches? > > > > > > > It would be quite bad to add new userspace-visible stats and to then > > take them away again. > > > yes. > > > But given that memcg-add-stats-to-monitor-soft_limit-reclaim.patch is > > queued for 2.6.39-rc1, we could proceed with that plan and then make > > sure that Johannes's changes are merged either prior to 2.6.40 or > > they are never merged at all. > > > > Or we could just leave out the stats until we're sure. Not having them > > for a while is not as bad as adding them and then removing them. > > > > I agree. I'm okay with removing them for a while. Johannes and Ying, could you > make a concensus ? IMHO, Johannes' work for making soft-limit co-operative with > hirerachical reclaim makes sense and agree to leave counter name as it is. > After reading threads, an another idea comes. Johannes' soft_limit just works when the hierarchy hit limit. I think pages are not reclaimed by soft_limit... it just reclaimed by the limit because of hierarchy. Right ? Hmm, I'm not sure using counter of softlimit or (new) counter of reclaimed-by-parent for that purpose. But I think this change of stat name is not necessary, anyway. 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/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org