From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf0-f198.google.com (mail-pf0-f198.google.com [209.85.192.198]) by kanga.kvack.org (Postfix) with ESMTP id 85FEF6B0387 for ; Thu, 23 Feb 2017 20:49:45 -0500 (EST) Received: by mail-pf0-f198.google.com with SMTP id j5so12946136pfb.3 for ; Thu, 23 Feb 2017 17:49:45 -0800 (PST) Received: from lgeamrelo11.lge.com (LGEAMRELO11.lge.com. [156.147.23.51]) by mx.google.com with ESMTP id w2si5820628pgo.389.2017.02.23.17.49.43 for ; Thu, 23 Feb 2017 17:49:44 -0800 (PST) Date: Fri, 24 Feb 2017 10:49:39 +0900 From: Minchan Kim Subject: Re: [PATCH V4 3/6] mm: move MADV_FREE pages into LRU_INACTIVE_FILE list Message-ID: <20170224014939.GC9818@bbox> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: owner-linux-mm@kvack.org List-ID: To: Shaohua Li Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Kernel-team@fb.com, mhocko@suse.com, hughd@google.com, hannes@cmpxchg.org, riel@redhat.com, mgorman@techsingularity.net, akpm@linux-foundation.org On Wed, Feb 22, 2017 at 10:50:41AM -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 Other than that Johannes pointed out, code itself looks good to me. However, I hope to merge this patch with next one. It's enough simple to merge, change behavior(about deactivation), mark_page_lazyfree is introduced but there is no callsite to use it in this patch. I don't think it's worth to separate. -- 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