From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx165.postini.com [74.125.245.165]) by kanga.kvack.org (Postfix) with SMTP id C42248D0020 for ; Fri, 11 May 2012 15:13:09 -0400 (EDT) Message-ID: <4FAD6449.2060201@parallels.com> Date: Fri, 11 May 2012 16:11:05 -0300 From: Glauber Costa MIME-Version: 1.0 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 Sender: owner-linux-mm@kvack.org List-ID: To: Christoph Lameter Cc: linux-kernel@vger.kernel.org, cgroups@vger.kernel.org, linux-mm@kvack.org, kamezawa.hiroyu@jp.fujitsu.com, Tejun Heo , Li Zefan , Greg Thelen , Suleiman Souhlal , Michal Hocko , Johannes Weiner , devel@openvz.org, Pekka Enberg 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, 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