From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx153.postini.com [74.125.245.153]) by kanga.kvack.org (Postfix) with SMTP id 619E36B007E for ; Wed, 29 Feb 2012 19:25:25 -0500 (EST) Message-ID: <4F4EC1AB.8050506@parallels.com> Date: Wed, 29 Feb 2012 21:24:11 -0300 From: Glauber Costa MIME-Version: 1.0 Subject: Re: [PATCH 04/10] memcg: Introduce __GFP_NOACCOUNT. 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> In-Reply-To: <20120301091044.1a62d42c.kamezawa.hiroyu@jp.fujitsu.com> Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: KAMEZAWA Hiroyuki 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 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? -- 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