From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail138.messagelabs.com (mail138.messagelabs.com [216.82.249.35]) by kanga.kvack.org (Postfix) with SMTP id 0091B6B01C6 for ; Tue, 15 Jun 2010 21:39:21 -0400 (EDT) Message-ID: <4C182097.2070603@redhat.com> Date: Tue, 15 Jun 2010 20:53:43 -0400 From: Rik van Riel MIME-Version: 1.0 Subject: Re: [PATCH 12/12] vmscan: Do not writeback pages in direct reclaim References: <1276514273-27693-1-git-send-email-mel@csn.ul.ie> <1276514273-27693-13-git-send-email-mel@csn.ul.ie> <4C16A567.4080000@redhat.com> <20100615114510.GE26788@csn.ul.ie> <4C17815A.8080402@redhat.com> <20100615135928.GK26788@csn.ul.ie> <4C178868.2010002@redhat.com> <20100615141601.GL26788@csn.ul.ie> <20100616091755.7121c7d3.kamezawa.hiroyu@jp.fujitsu.com> <4C181AFD.5060503@redhat.com> <20100616093958.00673123.kamezawa.hiroyu@jp.fujitsu.com> In-Reply-To: <20100616093958.00673123.kamezawa.hiroyu@jp.fujitsu.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org To: KAMEZAWA Hiroyuki Cc: Mel Gorman , linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, Dave Chinner , Chris Mason , Nick Piggin , Johannes Weiner , Christoph Hellwig , Andrew Morton List-ID: On 06/15/2010 08:39 PM, KAMEZAWA Hiroyuki wrote: > Hmm, or do you recommend no-dirty-page-writeback when a memcg hits limit ? > Maybe we'll see much swaps. > > I want to go with this for a while, changing memcg's behavior will took > some amounts of time, there are only a few developpers. One thing we can do, for kswapd, memcg and direct reclaim alike, is to tell the flusher threads to flush pages related to a pageout candidate page to disk. That way the reclaiming processes can wait on some disk IO to finish, while the flusher thread takes care of the actual flushing. That should also fix the "kswapd filesystem IO has really poor IO patterns" issue. There's no reason not to fix this issue the right way. -- All rights reversed -- 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