Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759330AbZFIITo (ORCPT ); Tue, 9 Jun 2009 04:19:44 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1759258AbZFIITY (ORCPT ); Tue, 9 Jun 2009 04:19:24 -0400 Received: from mail-gx0-f214.google.com ([209.85.217.214]:36625 "EHLO mail-gx0-f214.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758902AbZFIITV (ORCPT ); Tue, 9 Jun 2009 04:19:21 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type:content-transfer-encoding; b=HwG6gipSwNVHhysz3meT3j0ag2iOqEnvceerK9SlUy5HGqLueb7xEChEFVb3B4AjHf KY69VRD5wbHu5jIXX9Pidh0zD09/47wGq/lSXcwiZJR1PPr7meYK/zdHPnddmoWEI08n OykJSXa+c75cx+lpa3immtSYQkxPY//1FxhUE= MIME-Version: 1.0 In-Reply-To: <20090609164850.DD73.A69D9226@jp.fujitsu.com> References: <20090609161925.DD70.A69D9226@jp.fujitsu.com> <28c262360906090048x792fb3f9i6678298b693f6c5a@mail.gmail.com> <20090609164850.DD73.A69D9226@jp.fujitsu.com> Date: Tue, 9 Jun 2009 17:19:20 +0900 Message-ID: <28c262360906090119r6e881caq9b74028ba43567a7@mail.gmail.com> Subject: Re: [PATCH mmotm] vmscan: handle may_swap more strictly (Re: [PATCH mmotm] vmscan: fix may_swap handling for memcg) From: Minchan Kim To: KOSAKI Motohiro Cc: Daisuke Nishimura , LKML , linux-mm , Andrew Morton , Johannes Weiner , Balbir Singh , KAMEZAWA Hiroyuki Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1268 Lines: 40 On Tue, Jun 9, 2009 at 4:58 PM, KOSAKI Motohiro wrote: >> 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. > Hmm..Can that problem be happen in real system ? The file ratio is big means that file lru list scanning is so big but rotate is small. It means file lru have few reclaimable page. Isn't it ? I am confusing. Could you elaborate, please if you don't mind ? -- Kinds regards, Minchan Kim -- 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/