From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wm0-f69.google.com (mail-wm0-f69.google.com [74.125.82.69]) by kanga.kvack.org (Postfix) with ESMTP id 893996B0389 for ; Wed, 1 Mar 2017 10:14:34 -0500 (EST) Received: by mail-wm0-f69.google.com with SMTP id y187so17344228wmy.7 for ; Wed, 01 Mar 2017 07:14:34 -0800 (PST) Received: from mx2.suse.de (mx2.suse.de. [195.135.220.15]) by mx.google.com with ESMTPS id 7si7333010wmz.23.2017.03.01.07.14.33 for (version=TLS1 cipher=AES128-SHA bits=128/128); Wed, 01 Mar 2017 07:14:33 -0800 (PST) Date: Wed, 1 Mar 2017 16:14:32 +0100 From: Michal Hocko Subject: Re: [PATCH 4/9] mm: remove unnecessary reclaimability check from NUMA balancing target Message-ID: <20170301151432.GD11730@dhcp22.suse.cz> References: <20170228214007.5621-1-hannes@cmpxchg.org> <20170228214007.5621-5-hannes@cmpxchg.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170228214007.5621-5-hannes@cmpxchg.org> Sender: owner-linux-mm@kvack.org List-ID: To: Johannes Weiner Cc: Andrew Morton , Jia He , Mel Gorman , linux-mm@kvack.org, linux-kernel@vger.kernel.org, kernel-team@fb.com On Tue 28-02-17 16:40:02, Johannes Weiner wrote: > NUMA balancing already checks the watermarks of the target node to > decide whether it's a suitable balancing target. Whether the node is > reclaimable or not is irrelevant when we don't intend to reclaim. I guess the original intention was to skip nodes which are under strong memory pressure but I agree that this is questionable heuristic. > Signed-off-by: Johannes Weiner Acked-by: Michal Hocko > --- > mm/migrate.c | 3 --- > 1 file changed, 3 deletions(-) > > diff --git a/mm/migrate.c b/mm/migrate.c > index 2c63ac06791b..45a18be27b1a 100644 > --- a/mm/migrate.c > +++ b/mm/migrate.c > @@ -1718,9 +1718,6 @@ static bool migrate_balanced_pgdat(struct pglist_data *pgdat, > { > int z; > > - if (!pgdat_reclaimable(pgdat)) > - return false; > - > for (z = pgdat->nr_zones - 1; z >= 0; z--) { > struct zone *zone = pgdat->node_zones + z; > > -- > 2.11.1 -- Michal Hocko SUSE Labs -- 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 From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753334AbdCATZK (ORCPT ); Wed, 1 Mar 2017 14:25:10 -0500 Received: from mx2.suse.de ([195.135.220.15]:42937 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752462AbdCATY5 (ORCPT ); Wed, 1 Mar 2017 14:24:57 -0500 Date: Wed, 1 Mar 2017 16:14:32 +0100 From: Michal Hocko To: Johannes Weiner Cc: Andrew Morton , Jia He , Mel Gorman , linux-mm@kvack.org, linux-kernel@vger.kernel.org, kernel-team@fb.com Subject: Re: [PATCH 4/9] mm: remove unnecessary reclaimability check from NUMA balancing target Message-ID: <20170301151432.GD11730@dhcp22.suse.cz> References: <20170228214007.5621-1-hannes@cmpxchg.org> <20170228214007.5621-5-hannes@cmpxchg.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170228214007.5621-5-hannes@cmpxchg.org> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue 28-02-17 16:40:02, Johannes Weiner wrote: > NUMA balancing already checks the watermarks of the target node to > decide whether it's a suitable balancing target. Whether the node is > reclaimable or not is irrelevant when we don't intend to reclaim. I guess the original intention was to skip nodes which are under strong memory pressure but I agree that this is questionable heuristic. > Signed-off-by: Johannes Weiner Acked-by: Michal Hocko > --- > mm/migrate.c | 3 --- > 1 file changed, 3 deletions(-) > > diff --git a/mm/migrate.c b/mm/migrate.c > index 2c63ac06791b..45a18be27b1a 100644 > --- a/mm/migrate.c > +++ b/mm/migrate.c > @@ -1718,9 +1718,6 @@ static bool migrate_balanced_pgdat(struct pglist_data *pgdat, > { > int z; > > - if (!pgdat_reclaimable(pgdat)) > - return false; > - > for (z = pgdat->nr_zones - 1; z >= 0; z--) { > struct zone *zone = pgdat->node_zones + z; > > -- > 2.11.1 -- Michal Hocko SUSE Labs