From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757093Ab2IZQgz (ORCPT ); Wed, 26 Sep 2012 12:36:55 -0400 Received: from mail-pa0-f46.google.com ([209.85.220.46]:38523 "EHLO mail-pa0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755642Ab2IZQgx (ORCPT ); Wed, 26 Sep 2012 12:36:53 -0400 Date: Wed, 26 Sep 2012 09:36:48 -0700 From: Tejun Heo To: Michal Hocko Cc: Glauber Costa , linux-kernel@vger.kernel.org, cgroups@vger.kernel.org, kamezawa.hiroyu@jp.fujitsu.com, devel@openvz.org, linux-mm@kvack.org, Suleiman Souhlal , Frederic Weisbecker , Mel Gorman , David Rientjes , Johannes Weiner Subject: Re: [PATCH v3 04/13] kmem accounting basic infrastructure Message-ID: <20120926163648.GO16296@google.com> References: <1347977050-29476-1-git-send-email-glommer@parallels.com> <1347977050-29476-5-git-send-email-glommer@parallels.com> <20120926140347.GD15801@dhcp22.suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20120926140347.GD15801@dhcp22.suse.cz> User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, Michal, Glauber. On Wed, Sep 26, 2012 at 04:03:47PM +0200, Michal Hocko wrote: > Haven't we already discussed that a new memcg should inherit kmem_accounted > from its parent for use_hierarchy? > Say we have > root > | > A (kmem_accounted = 1, use_hierachy = 1) > \ > B (kmem_accounted = 0) > \ > C (kmem_accounted = 1) > > B find's itself in an awkward situation becuase it doesn't want to > account u+k but it ends up doing so becuase C. Do we really want this level of flexibility? What's wrong with a global switch at the root? I'm not even sure we want this to be optional at all. The only reason I can think of is that it might screw up some configurations in use which are carefully crafted to suit userland-only usage but for that isn't what we need a transition plan rather than another ultra flexible config option that not many really understand the implication of? In the same vein, do we really need both .kmem_accounted and config option? If someone is turning on MEMCG, just include kmem accounting. Thanks. -- tejun From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx140.postini.com [74.125.245.140]) by kanga.kvack.org (Postfix) with SMTP id 0A7886B0044 for ; Wed, 26 Sep 2012 12:36:53 -0400 (EDT) Received: by pbbrq2 with SMTP id rq2so2439729pbb.14 for ; Wed, 26 Sep 2012 09:36:53 -0700 (PDT) Date: Wed, 26 Sep 2012 09:36:48 -0700 From: Tejun Heo Subject: Re: [PATCH v3 04/13] kmem accounting basic infrastructure Message-ID: <20120926163648.GO16296@google.com> References: <1347977050-29476-1-git-send-email-glommer@parallels.com> <1347977050-29476-5-git-send-email-glommer@parallels.com> <20120926140347.GD15801@dhcp22.suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20120926140347.GD15801@dhcp22.suse.cz> Sender: owner-linux-mm@kvack.org List-ID: To: Michal Hocko Cc: Glauber Costa , linux-kernel@vger.kernel.org, cgroups@vger.kernel.org, kamezawa.hiroyu@jp.fujitsu.com, devel@openvz.org, linux-mm@kvack.org, Suleiman Souhlal , Frederic Weisbecker , Mel Gorman , David Rientjes , Johannes Weiner Hello, Michal, Glauber. On Wed, Sep 26, 2012 at 04:03:47PM +0200, Michal Hocko wrote: > Haven't we already discussed that a new memcg should inherit kmem_accounted > from its parent for use_hierarchy? > Say we have > root > | > A (kmem_accounted = 1, use_hierachy = 1) > \ > B (kmem_accounted = 0) > \ > C (kmem_accounted = 1) > > B find's itself in an awkward situation becuase it doesn't want to > account u+k but it ends up doing so becuase C. Do we really want this level of flexibility? What's wrong with a global switch at the root? I'm not even sure we want this to be optional at all. The only reason I can think of is that it might screw up some configurations in use which are carefully crafted to suit userland-only usage but for that isn't what we need a transition plan rather than another ultra flexible config option that not many really understand the implication of? In the same vein, do we really need both .kmem_accounted and config option? If someone is turning on MEMCG, just include kmem accounting. Thanks. -- tejun -- 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 From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tejun Heo Subject: Re: [PATCH v3 04/13] kmem accounting basic infrastructure Date: Wed, 26 Sep 2012 09:36:48 -0700 Message-ID: <20120926163648.GO16296@google.com> References: <1347977050-29476-1-git-send-email-glommer@parallels.com> <1347977050-29476-5-git-send-email-glommer@parallels.com> <20120926140347.GD15801@dhcp22.suse.cz> Mime-Version: 1.0 Return-path: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=sender:date:from:to:cc:subject:message-id:references:mime-version :content-type:content-disposition:in-reply-to:user-agent; bh=CYbQUDFNrG5WRz3VeuXBS2fEOq3veC2oE7BtqcsH/j8=; b=b9Ci/g+QEWi55Rk6vaEb3Qk8oVZSfcC7hSfnjuFngBTz2QK/5R/ekq0A3DLGEPwIQ5 1W55lS9o6eddG5IBKSDbQ/xJNgxNwRxPqAYOQRI5tp5AIaynHWddV5NSX5mKZPX3yThB pob81//oto63i0INEvDWUKbJppgkvYqxfRDBlZUs0Z3+WQ6kB9cpud/ZAbusBQ3k6W1g QNKrqbNbWVrswure/TrpI0ZMCtwu5y3ki15xqpIievSJwFi7qvg0HnwDMlg0VvE63+Xa QQCovrBhwrb77Oix9E84F2e2xbHnZHJXhQE2MI626C/in2k6DDKcJPv4MOjXhToECE6d 5jrA== Content-Disposition: inline In-Reply-To: <20120926140347.GD15801-2MMpYkNvuYDjFM9bn6wA6Q@public.gmane.org> Sender: cgroups-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-ID: Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Michal Hocko Cc: Glauber Costa , linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, kamezawa.hiroyu-+CUm20s59erQFUHtdCDX3A@public.gmane.org, devel-GEFAQzZX7r8dnm+yROfE0A@public.gmane.org, linux-mm-Bw31MaZKKs3YtjvyW6yDsg@public.gmane.org, Suleiman Souhlal , Frederic Weisbecker , Mel Gorman , David Rientjes , Johannes Weiner Hello, Michal, Glauber. On Wed, Sep 26, 2012 at 04:03:47PM +0200, Michal Hocko wrote: > Haven't we already discussed that a new memcg should inherit kmem_accounted > from its parent for use_hierarchy? > Say we have > root > | > A (kmem_accounted = 1, use_hierachy = 1) > \ > B (kmem_accounted = 0) > \ > C (kmem_accounted = 1) > > B find's itself in an awkward situation becuase it doesn't want to > account u+k but it ends up doing so becuase C. Do we really want this level of flexibility? What's wrong with a global switch at the root? I'm not even sure we want this to be optional at all. The only reason I can think of is that it might screw up some configurations in use which are carefully crafted to suit userland-only usage but for that isn't what we need a transition plan rather than another ultra flexible config option that not many really understand the implication of? In the same vein, do we really need both .kmem_accounted and config option? If someone is turning on MEMCG, just include kmem accounting. Thanks. -- tejun