Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933215Ab2EKTNI (ORCPT ); Fri, 11 May 2012 15:13:08 -0400 Received: from mx2.parallels.com ([64.131.90.16]:41274 "EHLO mx2.parallels.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932215Ab2EKTNG (ORCPT ); Fri, 11 May 2012 15:13:06 -0400 Message-ID: <4FAD6449.2060201@parallels.com> Date: Fri, 11 May 2012 16:11:05 -0300 From: Glauber Costa User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:10.0.1) Gecko/20120216 Thunderbird/10.0.1 MIME-Version: 1.0 To: Christoph Lameter CC: , , , , Tejun Heo , Li Zefan , Greg Thelen , Suleiman Souhlal , Michal Hocko , Johannes Weiner , , Pekka Enberg Subject: Re: [PATCH v2 04/29] slub: always get the cache from its page in kfree References: <1336758272-24284-1-git-send-email-glommer@parallels.com> <1336758272-24284-5-git-send-email-glommer@parallels.com> <4FAD531D.6030007@parallels.com> <4FAD566C.3000804@parallels.com> <4FAD585A.4070007@parallels.com> <4FAD5DA2.70803@parallels.com> <4FAD6169.8090409@parallels.com> In-Reply-To: Content-Type: text/plain; charset="ISO-8859-1"; format=flowed Content-Transfer-Encoding: 7bit X-Originating-IP: [187.105.248.83] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1862 Lines: 48 On 05/11/2012 04:09 PM, Christoph Lameter wrote: > On Fri, 11 May 2012, Glauber Costa wrote: > >> On 05/11/2012 03:56 PM, Christoph Lameter wrote: >>> On Fri, 11 May 2012, Glauber Costa wrote: >>> >>>> So we don't mix pages from multiple memcgs in the same cache - we believe >>>> that >>>> would be too confusing. >>> >>> Well subsystem create caches and other things that are shared between >>> multiple processes. How can you track that? >> >> Each process that belongs to a memcg triggers the creation of a new child kmem >> cache. > > I see that. But there are other subsystems from slab allocators that do > the same. There are also objects that may be used by multiple processes. This is also true for normal user pages. And then, we do what memcg does: first one to touch, gets accounted. I don't think deviating from the memcg behavior for user pages makes much sense here. A cache won't go away while it still have objects, even after the memcg is removed (it is marked as dead) > F.e what about shm? > >>>> /proc/slabinfo reflects this information, by listing the memcg-specific >>>> slabs. >>> >>> What about /sys/kernel/slab/*? >> >> From the PoV of the global system, what you'll see is something like: >> dentry , dentry(2:memcg1), dentry(2:memcg2), etc. > > Hmmm.. Would be better to have a hierachy there. /proc/slabinfo is more > legacy. I can take a look at that then. Assuming you agree with all the rest, is looking into that a pre-requisite for merging, or is something that can be deferred for a phase2 ? (We still don't do shrinkers, for instance, so this is sure to have a phase2) -- 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/