From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752194Ab0DPEXs (ORCPT ); Fri, 16 Apr 2010 00:23:48 -0400 Received: from fgwmail7.fujitsu.co.jp ([192.51.44.37]:49399 "EHLO fgwmail7.fujitsu.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751884Ab0DPEXo (ORCPT ); Fri, 16 Apr 2010 00:23:44 -0400 X-SecurityPolicyCheck-FJ: OK by FujitsuOutboundMailChecker v1.3.1 Date: Fri, 16 Apr 2010 13:18:23 +0900 From: KAMEZAWA Hiroyuki To: KAMEZAWA Hiroyuki Cc: Dave Chinner , linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-fsdevel@vger.kernel.org Subject: Re: [PATCH] mm: disallow direct reclaim page writeback Message-Id: <20100416131823.c874125a.kamezawa.hiroyu@jp.fujitsu.com> In-Reply-To: <20100416101339.a501f554.kamezawa.hiroyu@jp.fujitsu.com> References: <1271117878-19274-1-git-send-email-david@fromorbit.com> <20100416101339.a501f554.kamezawa.hiroyu@jp.fujitsu.com> Organization: FUJITSU Co. LTD. X-Mailer: Sylpheed 3.0.2 (GTK+ 2.10.14; i686-pc-mingw32) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 16 Apr 2010 10:13:39 +0900 KAMEZAWA Hiroyuki wrote: > Hmm. Then, if memoy cgroup is filled by dirty pages, it can't kick writeback > and has to wait for someone else's writeback ? > > How long this will take ? > # mount -t cgroup none /cgroup -o memory > # mkdir /cgroup/A > # echo 20M > /cgroup/A/memory.limit_in_bytes > # echo $$ > /cgroup/A/tasks > # dd if=/dev/zero of=./tmpfile bs=4096 count=1000000 > > Can memcg ask writeback thread to "Wake Up Now! and Write this out!" effectively ? > Hmm.. I saw an oom-kill while testing several cases but performance itself seems not to be far different with or without patch. But I'm unhappy with oom-kill, so some tweak for memcg will be necessary if we'll go with this. Thanks, -Kame