From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1032381Ab2CSSDg (ORCPT ); Mon, 19 Mar 2012 14:03:36 -0400 Received: from mx1.redhat.com ([209.132.183.28]:11968 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1030649Ab2CSSDe (ORCPT ); Mon, 19 Mar 2012 14:03:34 -0400 Message-ID: <4F6774E8.2050202@redhat.com> Date: Mon, 19 Mar 2012 14:03:20 -0400 From: Rik van Riel User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:10.0.1) Gecko/20120216 Thunderbird/10.0.1 MIME-Version: 1.0 To: Konstantin Khlebnikov CC: "linux-mm@kvack.org" , Andrew Morton , "linux-kernel@vger.kernel.org" , Hugh Dickins , Minchan Kim , Mel Gorman , Johannes Weiner , KAMEZAWA Hiroyuki Subject: Re: [PATCH] mm: forbid lumpy-reclaim in shrink_active_list() References: <20120319091821.17716.54031.stgit@zurg> <4F676FA4.50905@redhat.com> <4F6773CC.2010705@openvz.org> In-Reply-To: <4F6773CC.2010705@openvz.org> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 03/19/2012 01:58 PM, Konstantin Khlebnikov wrote: > Rik van Riel wrote: >> On 03/19/2012 05:18 AM, Konstantin Khlebnikov wrote: >>> This patch reset reclaim mode in shrink_active_list() to >>> RECLAIM_MODE_SINGLE | RECLAIM_MODE_ASYNC. >>> (sync/async sign is used only in shrink_page_list and does not affect >>> shrink_active_list) >>> >>> Currenly shrink_active_list() sometimes works in lumpy-reclaim mode, >>> if RECLAIM_MODE_LUMPYRECLAIM left over from earlier >>> shrink_inactive_list(). >>> Meanwhile, in age_active_anon() sc->reclaim_mode is totally zero. >>> So, current behavior is too complex and confusing, all this looks >>> like bug. >>> >>> In general, shrink_active_list() populate inactive list for next >>> shrink_inactive_list(). >>> Lumpy shring_inactive_list() isolate pages around choosen one from >>> both active and >>> inactive lists. So, there no reasons for lumpy-isolation in >>> shrink_active_list() >>> >>> Proposed-by: Hugh Dickins >>> Link: https://lkml.org/lkml/2012/3/15/583 >>> Signed-off-by: Konstantin Khlebnikov >> >> Confirmed, this is already done by commit >> 26f5f2f1aea7687565f55c20d69f0f91aa644fb8 in the >> linux-next tree. >> > > No, your patch fix this problem only if CONFIG_COMPACTION=y True. It was done that way, because Mel explained to me that deactivating a whole chunk of active pages at once is a desired feature that makes it more likely that a whole contiguous chunk of pages will eventually reach the end of the inactive list. -- All rights reversed