From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755036Ab2CFDG5 (ORCPT ); Mon, 5 Mar 2012 22:06:57 -0500 Received: from e23smtp09.au.ibm.com ([202.81.31.142]:45262 "EHLO e23smtp09.au.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754093Ab2CFDGz (ORCPT ); Mon, 5 Mar 2012 22:06:55 -0500 Date: Tue, 6 Mar 2012 13:38:09 +1100 From: David Gibson To: "Aneesh Kumar K.V" Cc: Andrew Morton , linux-mm@kvack.org, mgorman@suse.de, kamezawa.hiroyu@jp.fujitsu.com, dhillf@gmail.com, aarcange@redhat.com, mhocko@suse.cz, hannes@cmpxchg.org, linux-kernel@vger.kernel.org, cgroups@vger.kernel.org Subject: Re: [PATCH -V2 0/9] memcg: add HugeTLB resource tracking Message-ID: <20120306023809.GF12818@truffala.fritz.box> Mail-Followup-To: David Gibson , "Aneesh Kumar K.V" , Andrew Morton , linux-mm@kvack.org, mgorman@suse.de, kamezawa.hiroyu@jp.fujitsu.com, dhillf@gmail.com, aarcange@redhat.com, mhocko@suse.cz, hannes@cmpxchg.org, linux-kernel@vger.kernel.org, cgroups@vger.kernel.org References: <1330593380-1361-1-git-send-email-aneesh.kumar@linux.vnet.ibm.com> <20120301144029.545a5589.akpm@linux-foundation.org> <20120302032853.GB2728@truffala.fritz.box> <87fwdodyr0.fsf@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <87fwdodyr0.fsf@linux.vnet.ibm.com> User-Agent: Mutt/1.5.21 (2010-09-15) x-cbid: 12030517-3568-0000-0000-000001517C2C Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, Mar 04, 2012 at 11:39:23PM +0530, Aneesh Kumar K.V wrote: > On Fri, 2 Mar 2012 14:28:53 +1100, David Gibson wrote: > > On Thu, Mar 01, 2012 at 02:40:29PM -0800, Andrew Morton wrote: > > > On Thu, 1 Mar 2012 14:46:11 +0530 > > > "Aneesh Kumar K.V" wrote: > > > > > > > This patchset implements a memory controller extension to control > > > > HugeTLB allocations. It is similar to the existing hugetlb quota > > > > support in that, the limit is enforced at mmap(2) time and not at > > > > fault time. HugeTLB's quota mechanism limits the number of huge pages > > > > that can allocated per superblock. > > > > > > > > For shared mappings we track the regions mapped by a task along with the > > > > memcg. We keep the memory controller charged even after the task > > > > that did mmap(2) exits. Uncharge happens during truncate. For Private > > > > mappings we charge and uncharge from the current task cgroup. > > > > > > I haven't begin to get my head around this yet, but I'd like to draw > > > your attention to https://lkml.org/lkml/2012/2/15/548. That fix has > > > been hanging around for a while, but I haven't done anything with it > > > yet because I don't like its additional blurring of the separation > > > between hugetlb core code and hugetlbfs. I want to find time to sit > > > down and see if the fix can be better architected but haven't got > > > around to that yet. > > > > So.. that version of the fix I specifically rebuilt to address your > > concerns about that blurring - in fact I think it reduces the current > > layer blurring. I haven't had any reply - what problems do see it as > > still having? > > https://lkml.org/lkml/2012/2/16/179 ? Ah. Missed that reply somehow. Odd. Replied now and I'll respin accordingly. > That is a serious issue isn't it ? Yes, it is. And it's been around for a long, long time. -- David Gibson | I'll have my music baroque, and my code david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_ | _way_ _around_! http://www.ozlabs.org/~dgibson