From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx143.postini.com [74.125.245.143]) by kanga.kvack.org (Postfix) with SMTP id A9A4B6B00E8 for ; Mon, 19 Mar 2012 14:03:27 -0400 (EDT) Message-ID: <4F6774E8.2050202@redhat.com> Date: Mon, 19 Mar 2012 14:03:20 -0400 From: Rik van Riel MIME-Version: 1.0 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: owner-linux-mm@kvack.org List-ID: 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 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 -- 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/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org