From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754994Ab3ENReu (ORCPT ); Tue, 14 May 2013 13:34:50 -0400 Received: from mx1.redhat.com ([209.132.183.28]:6194 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751936Ab3ENRet (ORCPT ); Tue, 14 May 2013 13:34:49 -0400 Message-ID: <51927531.8010507@redhat.com> Date: Tue, 14 May 2013 13:32:33 -0400 From: Rik van Riel User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/17.0 Thunderbird/17.0 MIME-Version: 1.0 To: Minchan Kim CC: Andrew Morton , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Mel Gorman , Johannes Weiner , Kamezawa Hiroyuki , Michal Hocko , Hugh Dickins Subject: Re: [RFC 4/4] mm: free reclaimed pages instantly without depending next reclaim References: <1368411048-3753-1-git-send-email-minchan@kernel.org> <1368411048-3753-5-git-send-email-minchan@kernel.org> In-Reply-To: <1368411048-3753-5-git-send-email-minchan@kernel.org> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 05/12/2013 10:10 PM, Minchan Kim wrote: > Normally, file I/O for reclaiming is asynchronous so that > when page writeback is completed, reclaimed page will be > rotated into LRU tail for fast reclaiming in next turn. > But it makes unnecessary CPU overhead and more iteration with higher > priority of reclaim could reclaim too many pages than needed > pages. > > This patch frees reclaimed pages by paging out instantly without > rotating back them into LRU's tail when the I/O is completed so > that we can get out of reclaim loop as soon as poosbile and avoid > unnecessary CPU overhead for moving them. > > Signed-off-by: Minchan Kim I like this approach and am looking forward to your v2 series, with the reworked patch 3/4.