From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Thu, 20 Sep 2007 11:44:10 -0700 (PDT) From: Christoph Lameter Subject: Re: [patch 7/8] oom: only kill tasks that share zones with zonelist In-Reply-To: Message-ID: References: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org Return-Path: To: David Rientjes Cc: Andrew Morton , Andrea Arcangeli , Rik van Riel , linux-mm@kvack.org, Paul Jackson List-ID: On Thu, 20 Sep 2007, David Rientjes wrote: > On Thu, 20 Sep 2007, Christoph Lameter wrote: > > > > Setting the CONSTRAINT_MEMORY_POLICY case aside for a moment, what stops > > > us from getting rid of taking callback_mutex and simply relying on the > > > following to filter for candidate tasks: > > > > > > do_each_thread(g, p) { > > > ... > > > /* > > > * Check if it will do any good to kill this task based > > > * on where it is allowed to allocate. > > > */ > > > if (!nodes_intersects(current->mems_allowed, > > > p->mems_allowed)) > > > continue; > > > ... > > > } while_each_thread(g, p); > > > > A global scan over all processes is expensive and may take a long time if > > you have a 100000 or so of them. > > > > Yeah, I understand that. Paul and I talked about it a while ago and > decided that a per-cpuset file 'oom_kill_asking_task' could be implemented > to determine whether the OOM killer would simply kill current or go > through select_bad_process() in the CONSTRAINT_CPUSET case to address that > problem. Let me know if that doesn't seem good enough. There are still allocations that are not constrained to a cpuset. If the has an OOM condition on an allocation that is not constrained then the above may still cause more troubles. -- 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