From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx177.postini.com [74.125.245.177]) by kanga.kvack.org (Postfix) with SMTP id B214E6B002C for ; Thu, 1 Mar 2012 01:07:26 -0500 (EST) Received: from m4.gw.fujitsu.co.jp (unknown [10.0.50.74]) by fgwmail5.fujitsu.co.jp (Postfix) with ESMTP id 64BA53EE0AE for ; Thu, 1 Mar 2012 15:07:24 +0900 (JST) Received: from smail (m4 [127.0.0.1]) by outgoing.m4.gw.fujitsu.co.jp (Postfix) with ESMTP id 4F35245DE4F for ; Thu, 1 Mar 2012 15:07:24 +0900 (JST) Received: from s4.gw.fujitsu.co.jp (s4.gw.fujitsu.co.jp [10.0.50.94]) by m4.gw.fujitsu.co.jp (Postfix) with ESMTP id 2E1BA45DE4D for ; Thu, 1 Mar 2012 15:07:24 +0900 (JST) Received: from s4.gw.fujitsu.co.jp (localhost.localdomain [127.0.0.1]) by s4.gw.fujitsu.co.jp (Postfix) with ESMTP id 227C51DB803B for ; Thu, 1 Mar 2012 15:07:24 +0900 (JST) Received: from m107.s.css.fujitsu.com (m107.s.css.fujitsu.com [10.240.81.147]) by s4.gw.fujitsu.co.jp (Postfix) with ESMTP id BFA3A1DB8037 for ; Thu, 1 Mar 2012 15:07:23 +0900 (JST) Date: Thu, 1 Mar 2012 15:05:37 +0900 From: KAMEZAWA Hiroyuki Subject: Re: [PATCH 04/10] memcg: Introduce __GFP_NOACCOUNT. Message-Id: <20120301150537.8996bbf6.kamezawa.hiroyu@jp.fujitsu.com> In-Reply-To: <4F4EC1AB.8050506@parallels.com> References: <1330383533-20711-1-git-send-email-ssouhlal@FreeBSD.org> <1330383533-20711-5-git-send-email-ssouhlal@FreeBSD.org> <20120229150041.62c1feeb.kamezawa.hiroyu@jp.fujitsu.com> <20120301091044.1a62d42c.kamezawa.hiroyu@jp.fujitsu.com> <4F4EC1AB.8050506@parallels.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Glauber Costa Cc: Suleiman Souhlal , Suleiman Souhlal , cgroups@vger.kernel.org, penberg@kernel.org, yinghan@google.com, hughd@google.com, gthelen@google.com, linux-mm@kvack.org, devel@openvz.org On Wed, 29 Feb 2012 21:24:11 -0300 Glauber Costa wrote: > On 02/29/2012 09:10 PM, KAMEZAWA Hiroyuki wrote: > > On Wed, 29 Feb 2012 11:09:50 -0800 > > Suleiman Souhlal wrote: > > > >> On Tue, Feb 28, 2012 at 10:00 PM, KAMEZAWA Hiroyuki > >> wrote: > >>> On Mon, 27 Feb 2012 14:58:47 -0800 > >>> Suleiman Souhlal wrote: > >>> > >>>> This is used to indicate that we don't want an allocation to be accounted > >>>> to the current cgroup. > >>>> > >>>> Signed-off-by: Suleiman Souhlal > >>> > >>> I don't like this. > >>> > >>> Please add > >>> > >>> ___GFP_ACCOUNT "account this allocation to memcg" > >>> > >>> Or make this as slab's flag if this work is for slab allocation. > >> > >> We would like to account for all the slab allocations that happen in > >> process context. > >> > >> Manually marking every single allocation or kmem_cache with a GFP flag > >> really doesn't seem like the right thing to do.. > >> > >> Can you explain why you don't like this flag? > >> > > > > For example, tcp buffer limiting has another logic for buffer size controling. > > _AND_, most of kernel pages are not reclaimable at all. > > I think you should start from reclaimable caches as dcache, icache etc. > > > > If you want to use this wider, you can discuss > > > > + #define GFP_KERNEL (.....| ___GFP_ACCOUNT) > > > > in future. I'd like to see small start because memory allocation failure > > is always terrible and make the system unstable. Even if you notify > > "Ah, kernel memory allocation failed because of memory.limit? and > > many unreclaimable memory usage. Please tweak the limitation or kill tasks!!" > > > > The user can't do anything because he can't create any new task because of OOM. > > > > The system will be being unstable until an admin, who is not under any limit, > > tweaks something or reboot the system. > > > > Please do small start until you provide Eco-System to avoid a case that > > the admin cannot login and what he can do was only reboot. > > > Having the root cgroup to be always unlimited should already take care > of the most extreme cases, right? > If an admin can login into root cgroup ;) Anyway, if someone have a container under cgroup via hosting service, he can do noting if oom killer cannot recover his container. It can be caused by kernel memory limit. And I'm not sure he can do shutdown because he can't login. Thanks, -Kame -- 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