From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx142.postini.com [74.125.245.142]) by kanga.kvack.org (Postfix) with SMTP id 98CB06B005A for ; Thu, 6 Sep 2012 08:12:57 -0400 (EDT) Message-ID: <50489270.7060108@parallels.com> Date: Thu, 6 Sep 2012 16:09:20 +0400 From: Glauber Costa MIME-Version: 1.0 Subject: Re: [PATCH v2] memcg: first step towards hierarchical controller References: <20120904130905.GA15683@dhcp22.suse.cz> <504601B8.2050907@parallels.com> <20120904143552.GB15683@dhcp22.suse.cz> <50461241.5010300@parallels.com> <20120904145414.GC15683@dhcp22.suse.cz> <50461610.30305@parallels.com> <20120904162501.GE15683@dhcp22.suse.cz> <504709D4.2010800@parallels.com> <20120905144942.GH5388@dhcp22.suse.cz> <20120905201238.GE13737@google.com> <20120906120623.GE22426@dhcp22.suse.cz> In-Reply-To: <20120906120623.GE22426@dhcp22.suse.cz> Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Michal Hocko Cc: Tejun Heo , linux-kernel@vger.kernel.org, cgroups@vger.kernel.org, linux-mm@kvack.org, Dave Jones , Ben Hutchings , Peter Zijlstra , Paul Turner , Lennart Poettering , Kay Sievers , Kamezawa Hiroyuki , Johannes Weiner On 09/06/2012 04:06 PM, Michal Hocko wrote: > On Wed 05-09-12 13:12:38, Tejun Heo wrote: >> Hello, Michal. >> >> On Wed, Sep 05, 2012 at 04:49:42PM +0200, Michal Hocko wrote: >>> Can we settle on the following 3 steps? >>> 1) warn about "flat" hierarchies (give it X releases) - I will push it >>> to as many Suse code streams as possible (hope other distributions >>> could do the same) >> >> I think I'm just gonna trigger WARN from cgroup core if anyone tries >> to create hierarchy with a controller which doesn't support full >> hierarchy. WARN_ON_ONCE() at first and then WARN_ON() on each >> creation later on. > > How do you find out that a controller is not fully hierarchical? Memory > controller can be both. > >>> 2) flip the default on the root cgroup & warn when somebody tries to >>> change it to 0 (give it another X releases) that the knob will be >>> removed >>> 3) remove the knob and the whole nonsese >>> 4) revert 3 if somebody really objects >> >> If we can get to 3, I don't think 4 would be a problem. > > Agreed. > Just so I understand it: Michal clearly objected before folding his patch with my Kconfig patch. But is there still opposition to merge both? By having it default-n, only people that are either sure that this is safe for them, or have more clearly defined lifecycles could set it. -- 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