Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752203Ab2JQWMl (ORCPT ); Wed, 17 Oct 2012 18:12:41 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:57080 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751817Ab2JQWMg (ORCPT ); Wed, 17 Oct 2012 18:12:36 -0400 Date: Wed, 17 Oct 2012 15:12:35 -0700 From: Andrew Morton To: Glauber Costa Cc: , , Mel Gorman , Tejun Heo , Michal Hocko , Johannes Weiner , , Christoph Lameter , David Rientjes , Pekka Enberg , , , Pekka Enberg , Suleiman Souhlal Subject: Re: [PATCH v5 11/14] memcg: allow a memcg with kmem charges to be destructed. Message-Id: <20121017151235.1e5d6f21.akpm@linux-foundation.org> In-Reply-To: <1350382611-20579-12-git-send-email-glommer@parallels.com> References: <1350382611-20579-1-git-send-email-glommer@parallels.com> <1350382611-20579-12-git-send-email-glommer@parallels.com> X-Mailer: Sylpheed 3.0.2 (GTK+ 2.20.1; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1330 Lines: 32 On Tue, 16 Oct 2012 14:16:48 +0400 Glauber Costa wrote: > Because the ultimate goal of the kmem tracking in memcg is to track slab > pages as well, It is? For a major patchset such as this, it's pretty important to discuss such long-term plans in the top-level discussion. Covering things such as expected complexity, expected performance hit, how these plans affected the current implementation, etc. The main reason for this is that if the future plans appear to be of doubtful feasibility and the current implementation isn't sufficiently useful without the future stuff, we shouldn't merge the current implementation. It's a big issue! > we can't guarantee that we'll always be able to point a > page to a particular process, and migrate the charges along with it - > since in the common case, a page will contain data belonging to multiple > processes. > > Because of that, when we destroy a memcg, we only make sure the > destruction will succeed by discounting the kmem charges from the user > charges when we try to empty the cgroup. > > ... > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/