From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from sd0109e.au.ibm.com (d23rh905.au.ibm.com [202.81.18.225]) by ausmtp04.au.ibm.com (8.13.8/8.13.8) with ESMTP id m9T4NDnq122072 for ; Wed, 29 Oct 2008 15:23:14 +1100 Received: from d23av01.au.ibm.com (d23av01.au.ibm.com [9.190.234.96]) by sd0109e.au.ibm.com (8.13.8/8.13.8/NCO v9.1) with ESMTP id m9T48M4f216440 for ; Wed, 29 Oct 2008 15:08:25 +1100 Received: from d23av01.au.ibm.com (loopback [127.0.0.1]) by d23av01.au.ibm.com (8.12.11.20060308/8.13.3) with ESMTP id m9T48M6c023019 for ; Wed, 29 Oct 2008 15:08:22 +1100 Message-ID: <4907E1B4.6000406@linux.vnet.ibm.com> Date: Wed, 29 Oct 2008 09:38:20 +0530 From: Balbir Singh Reply-To: balbir@linux.vnet.ibm.com MIME-Version: 1.0 Subject: Re: [discuss][memcg] oom-kill extension References: <20081029113826.cc773e21.kamezawa.hiroyu@jp.fujitsu.com> In-Reply-To: <20081029113826.cc773e21.kamezawa.hiroyu@jp.fujitsu.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: KAMEZAWA Hiroyuki Cc: "linux-mm@kvack.org" , "menage@google.com" List-ID: KAMEZAWA Hiroyuki wrote: > Under memory resource controller(memcg), oom-killer can be invoked when it > reaches limit and no memory can be reclaimed. > > In general, not under memcg, oom-kill(or panic) is an only chance to recover > the system because there is no available memory. But when oom occurs under > memcg, it just reaches limit and it seems we can do something else. > > Does anyone have plan to enhance oom-kill ? > > What I can think of now is > - add an notifier to user-land. > - receiver of notify should work in another cgroup. The discussion at the mini-summit was to notify a FIFO in the cgroup and any application can listen in for events. > - automatically extend the limit as emergency No.. I don't like this > - trigger fail-over process. I had suggested memrlimits for the ability to fail application allocations, but no-one liked the idea. We can still implement overcommit functionality if needed and catch failures at allocation time. > - automatically create a precise report of OOM. > - record snapshot of 'ps -elf' and so on of memcg which triggers oom. > > - freeze processes under cgroup. > - maybe freezer cgroup should be mounted at the same time. > - can we add memcg-oom-freezing-point in somewhere we can sleep ? > > Is there a chance to add oom_notifier to memcg ? (netlink ?) > Yes, we should add the oom-notifier. We already have cgroupstats if you want to make use of it. > But the real problem is that what we can do in the kernel is limited > and we need proper userland, anyway ;) > Agreed. -- Balbir -- 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