From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx120.postini.com [74.125.245.120]) by kanga.kvack.org (Postfix) with SMTP id 30A4C6B00E9 for ; Tue, 10 Apr 2012 02:01:19 -0400 (EDT) Received: from m3.gw.fujitsu.co.jp (unknown [10.0.50.73]) by fgwmail6.fujitsu.co.jp (Postfix) with ESMTP id 58C3C3EE0BB for ; Tue, 10 Apr 2012 15:01:17 +0900 (JST) Received: from smail (m3 [127.0.0.1]) by outgoing.m3.gw.fujitsu.co.jp (Postfix) with ESMTP id 3F5C145DEA6 for ; Tue, 10 Apr 2012 15:01:17 +0900 (JST) Received: from s3.gw.fujitsu.co.jp (s3.gw.fujitsu.co.jp [10.0.50.93]) by m3.gw.fujitsu.co.jp (Postfix) with ESMTP id 2873845DE7E for ; Tue, 10 Apr 2012 15:01:17 +0900 (JST) Received: from s3.gw.fujitsu.co.jp (localhost.localdomain [127.0.0.1]) by s3.gw.fujitsu.co.jp (Postfix) with ESMTP id 0EAD11DB803E for ; Tue, 10 Apr 2012 15:01:17 +0900 (JST) Received: from m107.s.css.fujitsu.com (m107.s.css.fujitsu.com [10.240.81.147]) by s3.gw.fujitsu.co.jp (Postfix) with ESMTP id AEB5E1DB8040 for ; Tue, 10 Apr 2012 15:01:16 +0900 (JST) Message-ID: <4F83CC40.7030406@jp.fujitsu.com> Date: Tue, 10 Apr 2012 14:59:28 +0900 From: KAMEZAWA Hiroyuki MIME-Version: 1.0 Subject: Re: [patch v2] thp, memcg: split hugepage for memcg oom on cow References: <4F838385.9070309@jp.fujitsu.com> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: David Rientjes Cc: Andrew Morton , Andrea Arcangeli , Johannes Weiner , linux-mm@kvack.org (2012/04/10 14:42), David Rientjes wrote: > On COW, a new hugepage is allocated and charged to the memcg. If the > system is oom or the charge to the memcg fails, however, the fault > handler will return VM_FAULT_OOM which results in an oom kill. > > Instead, it's possible to fallback to splitting the hugepage so that the > COW results only in an order-0 page being allocated and charged to the > memcg which has a higher liklihood to succeed. This is expensive because > the hugepage must be split in the page fault handler, but it is much > better than unnecessarily oom killing a process. > > Signed-off-by: David Rientjes Seems nice to me. Acked-by: KAMEZAWA Hiroyuki -- 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