Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758894AbZFIH64 (ORCPT ); Tue, 9 Jun 2009 03:58:56 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1758891AbZFIH6l (ORCPT ); Tue, 9 Jun 2009 03:58:41 -0400 Received: from fgwmail5.fujitsu.co.jp ([192.51.44.35]:56521 "EHLO fgwmail5.fujitsu.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758460AbZFIH6k (ORCPT ); Tue, 9 Jun 2009 03:58:40 -0400 From: KOSAKI Motohiro To: Minchan Kim Subject: Re: [PATCH mmotm] vmscan: handle may_swap more strictly (Re: [PATCH mmotm] vmscan: fix may_swap handling for memcg) Cc: kosaki.motohiro@jp.fujitsu.com, Daisuke Nishimura , LKML , linux-mm , Andrew Morton , Johannes Weiner , Balbir Singh , KAMEZAWA Hiroyuki In-Reply-To: <28c262360906090048x792fb3f9i6678298b693f6c5a@mail.gmail.com> References: <20090609161925.DD70.A69D9226@jp.fujitsu.com> <28c262360906090048x792fb3f9i6678298b693f6c5a@mail.gmail.com> Message-Id: <20090609164850.DD73.A69D9226@jp.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Mailer: Becky! ver. 2.50.07 [ja] Date: Tue, 9 Jun 2009 16:58:36 +0900 (JST) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 869 Lines: 29 > Hi, KOSAKI. > > As you know, this problem caused by if condition(priority) in shrink_zone. > Let me have a question. > > Why do we have to prevent scan value calculation when the priority is zero ? > As I know, before split-lru, we didn't do it. > > Is there any specific issue in case of the priority is zero ? Yes. example: get_scan_ratio() return anon:80%, file=20%. and the system have 10000 anon pages and 10000 file pages. shrink_zone() picked up 8000 anon pages and 2000 file pages. it mean 8000 file pages aren't scanned at all. Oops, it can makes OOM-killer although system have droppable file cache. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/