From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752626AbcGSWVa (ORCPT ); Tue, 19 Jul 2016 18:21:30 -0400 Received: from mail-pa0-f51.google.com ([209.85.220.51]:36459 "EHLO mail-pa0-f51.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752418AbcGSWV2 (ORCPT ); Tue, 19 Jul 2016 18:21:28 -0400 Date: Tue, 19 Jul 2016 15:21:20 -0700 (PDT) From: David Rientjes X-X-Sender: rientjes@chino.kir.corp.google.com To: Vlastimil Babka cc: Andrew Morton , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Michal Hocko , Mel Gorman , Joonsoo Kim , Rik van Riel , Hugh Dickins Subject: Re: [PATCH 1/8] mm, compaction: don't isolate PageWriteback pages in MIGRATE_SYNC_LIGHT mode In-Reply-To: <20160718112302.27381-2-vbabka@suse.cz> Message-ID: References: <20160718112302.27381-1-vbabka@suse.cz> <20160718112302.27381-2-vbabka@suse.cz> User-Agent: Alpine 2.10 (DEB 1266 2009-07-14) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 18 Jul 2016, Vlastimil Babka wrote: > From: Hugh Dickins > > At present MIGRATE_SYNC_LIGHT is allowing __isolate_lru_page() to > isolate a PageWriteback page, which __unmap_and_move() then rejects > with -EBUSY: of course the writeback might complete in between, but > that's not what we usually expect, so probably better not to isolate it. > > When tested by stress-highalloc from mmtests, this has reduced the number of > page migrate failures by 60-70%. > > Signed-off-by: Hugh Dickins > Signed-off-by: Vlastimil Babka > Acked-by: Michal Hocko Acked-by: David Rientjes