From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail144.messagelabs.com (mail144.messagelabs.com [216.82.254.51]) by kanga.kvack.org (Postfix) with SMTP id 778B96B006A for ; Mon, 2 Nov 2009 03:41:49 -0500 (EST) Received: from m1.gw.fujitsu.co.jp ([10.0.50.71]) by fgwmail6.fujitsu.co.jp (Fujitsu Gateway) with ESMTP id nA28fkS5031072 for (envelope-from kamezawa.hiroyu@jp.fujitsu.com); Mon, 2 Nov 2009 17:41:46 +0900 Received: from smail (m1 [127.0.0.1]) by outgoing.m1.gw.fujitsu.co.jp (Postfix) with ESMTP id 5822945DE51 for ; Mon, 2 Nov 2009 17:41:46 +0900 (JST) Received: from s1.gw.fujitsu.co.jp (s1.gw.fujitsu.co.jp [10.0.50.91]) by m1.gw.fujitsu.co.jp (Postfix) with ESMTP id 345AE45DE4D for ; Mon, 2 Nov 2009 17:41:46 +0900 (JST) Received: from s1.gw.fujitsu.co.jp (localhost.localdomain [127.0.0.1]) by s1.gw.fujitsu.co.jp (Postfix) with ESMTP id 1DA741DB803F for ; Mon, 2 Nov 2009 17:41:46 +0900 (JST) Received: from ml13.s.css.fujitsu.com (ml13.s.css.fujitsu.com [10.249.87.103]) by s1.gw.fujitsu.co.jp (Postfix) with ESMTP id C5AC41DB803A for ; Mon, 2 Nov 2009 17:41:45 +0900 (JST) Date: Mon, 2 Nov 2009 17:39:12 +0900 From: KAMEZAWA Hiroyuki Subject: Re: [RFC][-mm][PATCH 4/6] oom-killer: fork bomb detector Message-Id: <20091102173912.601790b0.kamezawa.hiroyu@jp.fujitsu.com> In-Reply-To: <20091102162716.e7803741.kamezawa.hiroyu@jp.fujitsu.com> References: <20091102162244.9425e49b.kamezawa.hiroyu@jp.fujitsu.com> <20091102162716.e7803741.kamezawa.hiroyu@jp.fujitsu.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org To: KAMEZAWA Hiroyuki Cc: "linux-kernel@vger.kernel.org" , "linux-mm@kvack.org" , "kosaki.motohiro@jp.fujitsu.com" , aarcange@redhat.com, akpm@linux-foundation.org, minchan.kim@gmail.com, rientjes@google.com, vedran.furac@gmail.com, "hugh.dickins@tiscali.co.uk" List-ID: On Mon, 2 Nov 2009 16:27:16 +0900 KAMEZAWA Hiroyuki wrote: > - > - /* Try to kill a child first */ > + if (fork_bomb) { > + printk(KERN_ERR "possible fork-bomb is detected. kill them\n"); > + /* We need to kill the youngest one, at least */ > + rcu_read_lock(); > + for_each_process_reverse(c) { > + if (c == p) > + break; > + if (is_forkbomb_family(c, p)) { > + oom_kill_task(c); > + break; > + } > + } > + rcu_read_unlock(); > + } Kosaki said we should kill all under tree and "break" is unnecessay here. I nearly agree with him..after some experiments. But it seems the biggest problem is latecy by swap-out...before deciding OOM .... 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/ . Don't email: email@kvack.org