From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752220Ab2I0Mnf (ORCPT ); Thu, 27 Sep 2012 08:43:35 -0400 Received: from mx2.parallels.com ([64.131.90.16]:36676 "EHLO mx2.parallels.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751013Ab2I0Mne (ORCPT ); Thu, 27 Sep 2012 08:43:34 -0400 Message-ID: <50644923.2060008@parallels.com> Date: Thu, 27 Sep 2012 16:40:03 +0400 From: Glauber Costa User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:15.0) Gecko/20120911 Thunderbird/15.0.1 MIME-Version: 1.0 To: Michal Hocko CC: Tejun Heo , , , , , , Suleiman Souhlal , Frederic Weisbecker , Mel Gorman , David Rientjes , Johannes Weiner Subject: Re: [PATCH v3 04/13] kmem accounting basic infrastructure References: <50637298.2090904@parallels.com> <20120926221046.GA10453@mtj.dyndns.org> <506381B2.2060806@parallels.com> <20120926224235.GB10453@mtj.dyndns.org> <50638793.7060806@parallels.com> <20120926230807.GC10453@mtj.dyndns.org> <50638DBB.4000002@parallels.com> <20120926233334.GD10453@mtj.dyndns.org> <20120927121558.GB29104@dhcp22.suse.cz> <506444A7.5060303@parallels.com> <20120927124031.GC29104@dhcp22.suse.cz> In-Reply-To: <20120927124031.GC29104@dhcp22.suse.cz> Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 09/27/2012 04:40 PM, Michal Hocko wrote: > On Thu 27-09-12 16:20:55, Glauber Costa wrote: >> On 09/27/2012 04:15 PM, Michal Hocko wrote: >>> On Wed 26-09-12 16:33:34, Tejun Heo wrote: >>> [...] >>>>>> So, this seems properly crazy to me at the similar level of >>>>>> use_hierarchy fiasco. I'm gonna NACK on this. >>>>> >>>>> As I said: all use cases I particularly care about are covered by a >>>>> global switch. >>>>> >>>>> I am laying down my views because I really believe they make more sense. >>>>> But at some point, of course, I'll shut up if I believe I am a lone voice. >>>>> >>>>> I believe it should still be good to hear from mhocko and kame, but from >>>>> your point of view, would all the rest, plus the introduction of a >>>>> global switch make it acceptable to you? >>>> >>>> The only thing I'm whining about is per-node switch + silently >>>> ignoring past accounting, so if those two are solved, I think I'm >>>> pretty happy with the rest. >>> >>> I think that per-group "switch" is not nice as well but if we make it >>> hierarchy specific (which I am proposing for quite some time) and do not >>> let enable accounting for a group with tasks then we get both >>> flexibility and reasonable semantic. A global switch sounds too coars to >>> me and it really not necessary. >>> >>> Would this work with you? >>> >> >> How exactly would that work? AFAIK, we have a single memcg root, we >> can't have multiple memcg hierarchies in a system. Am I missing something? > > Well root is so different that we could consider the first level as the > real roots for hierarchies. > So let's favor clarity: What you are proposing is that the first level can have a switch for that, and the first level only. Is that right ? At first, I just want to understand what exactly is your proposal. This is not an endorsement of lack thereof.