From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755108AbbJOGFq (ORCPT ); Thu, 15 Oct 2015 02:05:46 -0400 Received: from LGEAMRELO13.lge.com ([156.147.23.53]:48211 "EHLO lgeamrelo13.lge.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754607AbbJOGFW (ORCPT ); Thu, 15 Oct 2015 02:05:22 -0400 X-Original-SENDERIP: 156.147.1.126 X-Original-MAILFROM: iamjoonsoo.kim@lge.com X-Original-SENDERIP: 10.177.222.138 X-Original-MAILFROM: iamjoonsoo.kim@lge.com Date: Thu, 15 Oct 2015 15:06:12 +0900 From: Joonsoo Kim To: Vlastimil Babka Cc: Andrew Morton , linux-kernel@vger.kernel.org, linux-mm@kvack.org, Mel Gorman , Rik van Riel , David Rientjes , Minchan Kim Subject: Re: [PATCH v2 9/9] mm/compaction: new threshold for compaction depleted zone Message-ID: <20151015060612.GD7566@js1304-P5Q-DELUXE> References: <1440382773-16070-1-git-send-email-iamjoonsoo.kim@lge.com> <1440382773-16070-10-git-send-email-iamjoonsoo.kim@lge.com> <561E4A6F.5070801@suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <561E4A6F.5070801@suse.cz> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Oct 14, 2015 at 02:28:31PM +0200, Vlastimil Babka wrote: > On 08/24/2015 04:19 AM, Joonsoo Kim wrote: > > Now, compaction algorithm become powerful. Migration scanner traverses > > whole zone range. So, old threshold for depleted zone which is designed > > to imitate compaction deferring approach isn't appropriate for current > > compaction algorithm. If we adhere to current threshold, 1, we can't > > avoid excessive overhead caused by compaction, because one compaction > > for low order allocation would be easily successful in any situation. > > > > This patch re-implements threshold calculation based on zone size and > > allocation requested order. We judge whther compaction possibility is > > depleted or not by number of successful compaction. Roughly, 1/100 > > of future scanned area should be allocated for high order page during > > one comaction iteration in order to determine whether zone's compaction > > possiblity is depleted or not. > > Finally finishing my review, sorry it took that long... > Ah... I forgot to mention that I really appreciate your help. Thanks for review!! Thanks!