From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail203.messagelabs.com (mail203.messagelabs.com [216.82.254.243]) by kanga.kvack.org (Postfix) with ESMTP id F152E6B004A for ; Thu, 2 Jun 2011 08:59:43 -0400 (EDT) Received: by bwz17 with SMTP id 17so1429214bwz.14 for ; Thu, 02 Jun 2011 05:59:40 -0700 (PDT) MIME-Version: 1.0 In-Reply-To: <20110602100007.GB20725@cmpxchg.org> References: <1306909519-7286-1-git-send-email-hannes@cmpxchg.org> <20110602073335.GA20630@cmpxchg.org> <20110602100007.GB20725@cmpxchg.org> Date: Thu, 2 Jun 2011 21:59:40 +0900 Message-ID: Subject: Re: [patch 0/8] mm: memcg naturalization -rc2 From: Hiroyuki Kamezawa Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Sender: owner-linux-mm@kvack.org List-ID: To: Johannes Weiner Cc: KAMEZAWA Hiroyuki , Daisuke Nishimura , Balbir Singh , Ying Han , Michal Hocko , Andrew Morton , Rik van Riel , Minchan Kim , KOSAKI Motohiro , Mel Gorman , Greg Thelen , Michel Lespinasse , linux-mm@kvack.org, linux-kernel@vger.kernel.org 2011/6/2 Johannes Weiner : > On Thu, Jun 02, 2011 at 06:06:51PM +0900, Hiroyuki Kamezawa wrote: >> 2011/6/2 Johannes Weiner : >> > On Thu, Jun 02, 2011 at 08:52:47AM +0900, Hiroyuki Kamezawa wrote: >> >> =A0 Hmm, how about splitting patch 2/8 into small patches and see wha= t happens in >> >> =A0 3.2 or 3.3 ? While that, we can make softlimit works better. >> >> =A0 (and once we do 2/8, our direction will be fixed to the direction= to >> >> remove global LRU.) >> > >> > Do you have specific parts in mind that could go stand-alone? >> > >> > One thing I can think of is splitting up those parts: >> > >> > =A01. move /target/ reclaim to generic code >> > >> > =A02. convert /global/ reclaim from global lru to hierarchy reclaim >> > =A0 =A0 including root_mem_cgroup >> >> Hmm, at brief look >> patch 2/8 >> =A0- hierarchy walk rewrite code should be stand alone and can be merged >> 1st, as clean-up > > You mean introducing mem_cgroup_hierarchy_walk() and make use of it in > mem_cgroup_hierarchical_reclaim() as a first step? > yes. I like to cut out a patch from a series and forward it to mainline, and make the series smaller. in some way... >> =A0- root cgroup LRU handling was required for performance. I think we >> removed tons of >> =A0 atomic ops and can remove that special handling personally. But this= change of >> =A0 root cgroup handling should be in separate patch. with performance r= eport. > > I disagree. > > With view on the whole patch series, linking ungrouped process pages > to the root_mem_cgroup is traded against > > =A0 1. linking ungrouped process pages to the global LRU > > =A0 2. linking grouped process pages to both the global LRU and the > =A0 =A0 =A0memcg LRU > > The comparison you propose is neither fair nor relevant because it > would never make sense to merge that patch without the others. If you show there is no performance regression when - memory cgroup is configured. - it's not disabled by boot option - there are only ROOT cgroup. (Then, I'd like to see score.) It seems your current series is a mixture of 2 works as "re-desgin of softlimit" and "removal of global LRU". I don't understand why you need 2 works at once. Above test is for the latter. You need another justification for the former= . So, I'd like to ask you to divide the series into 2 series. 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