From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751558AbdB0R6P (ORCPT ); Mon, 27 Feb 2017 12:58:15 -0500 Received: from gum.cmpxchg.org ([85.214.110.215]:37502 "EHLO gum.cmpxchg.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751451AbdB0R6L (ORCPT ); Mon, 27 Feb 2017 12:58:11 -0500 Date: Mon, 27 Feb 2017 12:15:33 -0500 From: Johannes Weiner To: Shaohua Li Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Kernel-team@fb.com, mhocko@suse.com, minchan@kernel.org, hughd@google.com, riel@redhat.com, mgorman@techsingularity.net, akpm@linux-foundation.org Subject: Re: [PATCH V5 3/6] mm: move MADV_FREE pages into LRU_INACTIVE_FILE list Message-ID: <20170227171533.GB20423@cmpxchg.org> References: <2f87063c1e9354677b7618c647abde77b07561e5.1487965799.git.shli@fb.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <2f87063c1e9354677b7618c647abde77b07561e5.1487965799.git.shli@fb.com> User-Agent: Mutt/1.7.2 (2016-11-26) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Feb 24, 2017 at 01:31:46PM -0800, Shaohua Li wrote: > madv MADV_FREE indicate pages are 'lazyfree'. They are still anonymous > pages, but they can be freed without pageout. To destinguish them > against normal anonymous pages, we clear their SwapBacked flag. > > MADV_FREE pages could be freed without pageout, so they pretty much like > used once file pages. For such pages, we'd like to reclaim them once > there is memory pressure. Also it might be unfair reclaiming MADV_FREE > pages always before used once file pages and we definitively want to > reclaim the pages before other anonymous and file pages. > > To speed up MADV_FREE pages reclaim, we put the pages into > LRU_INACTIVE_FILE list. The rationale is LRU_INACTIVE_FILE list is tiny > nowadays and should be full of used once file pages. Reclaiming > MADV_FREE pages will not have much interfere of anonymous and active > file pages. And the inactive file pages and MADV_FREE pages will be > reclaimed according to their age, so we don't reclaim too many MADV_FREE > pages too. Putting the MADV_FREE pages into LRU_INACTIVE_FILE_LIST also > means we can reclaim the pages without swap support. This idea is > suggested by Johannes. > > This patch doesn't move MADV_FREE pages to LRU_INACTIVE_FILE list yet to > avoid bisect failure, next patch will do it. > > The patch is based on Minchan's original patch. > > Cc: Michal Hocko > Cc: Minchan Kim > Cc: Hugh Dickins > Cc: Rik van Riel > Cc: Mel Gorman > Cc: Andrew Morton > Suggested-by: Johannes Weiner > Signed-off-by: Shaohua Li Acked-by: Johannes Weiner