From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932313AbcFVQI7 (ORCPT ); Wed, 22 Jun 2016 12:08:59 -0400 Received: from mx2.suse.de ([195.135.220.15]:36621 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932185AbcFVQI5 (ORCPT ); Wed, 22 Jun 2016 12:08:57 -0400 Subject: Re: [PATCH 21/27] mm, vmscan: Only wakeup kswapd once per node for the requested classzone To: Mel Gorman , Andrew Morton , Linux-MM References: <1466518566-30034-1-git-send-email-mgorman@techsingularity.net> <1466518566-30034-22-git-send-email-mgorman@techsingularity.net> Cc: Rik van Riel , Johannes Weiner , LKML From: Vlastimil Babka Message-ID: <23a86eb7-ffa2-4269-3acb-47b29d984a3c@suse.cz> Date: Wed, 22 Jun 2016 18:08:54 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.1.1 MIME-Version: 1.0 In-Reply-To: <1466518566-30034-22-git-send-email-mgorman@techsingularity.net> Content-Type: text/plain; charset=iso-8859-2; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 06/21/2016 04:16 PM, Mel Gorman wrote: > kswapd is woken when zones are below the low watermark but the wakeup > decision is not taking the classzone into account. Now that reclaim is > node-based, it is only required to wake kswapd once per node and only if > all zones are unbalanced for the requested classzone. > > Note that one node might be checked multiple times if the zonelist is ordered > by node because there is no cheap way of tracking what nodes have already > been visited. For zone-ordering, each node should be checked only once. > > Signed-off-by: Mel Gorman Acked-by: Vlastimil Babka