From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wi0-f171.google.com (mail-wi0-f171.google.com [209.85.212.171]) by kanga.kvack.org (Postfix) with ESMTP id E972F6B0032 for ; Wed, 10 Dec 2014 04:55:04 -0500 (EST) Received: by mail-wi0-f171.google.com with SMTP id bs8so10601052wib.4 for ; Wed, 10 Dec 2014 01:55:04 -0800 (PST) Received: from mx2.suse.de (cantor2.suse.de. [195.135.220.15]) by mx.google.com with ESMTPS id hu8si19525685wib.9.2014.12.10.01.55.03 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Wed, 10 Dec 2014 01:55:03 -0800 (PST) Message-ID: <54881876.70309@suse.cz> Date: Wed, 10 Dec 2014 10:55:02 +0100 From: Vlastimil Babka MIME-Version: 1.0 Subject: Re: [PATCH 2/4] mm/page_alloc: expands broken freepage to proper buddy list when steal References: <1418022980-4584-1-git-send-email-iamjoonsoo.kim@lge.com> <1418022980-4584-3-git-send-email-iamjoonsoo.kim@lge.com> <54856F88.8090300@suse.cz> <20141210063840.GC13371@js1304-P5Q-DELUXE> In-Reply-To: <20141210063840.GC13371@js1304-P5Q-DELUXE> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Joonsoo Kim Cc: Andrew Morton , Mel Gorman , David Rientjes , Rik van Riel , linux-mm@kvack.org, linux-kernel@vger.kernel.org On 12/10/2014 07:38 AM, Joonsoo Kim wrote: > On Mon, Dec 08, 2014 at 10:29:44AM +0100, Vlastimil Babka wrote: >> On 12/08/2014 08:16 AM, Joonsoo Kim wrote: >>> There is odd behaviour when we steal freepages from other migratetype >>> buddy list. In try_to_steal_freepages(), we move all freepages in >>> the pageblock that founded freepage is belong to to the request >>> migratetype in order to mitigate fragmentation. If the number of moved >>> pages are enough to change pageblock migratetype, there is no problem. If >>> not enough, we don't change pageblock migratetype and add broken freepages >>> to the original migratetype buddy list rather than request migratetype >>> one. For me, this is odd, because we already moved all freepages in this >>> pageblock to the request migratetype. This patch fixes this situation to >>> add broken freepages to the request migratetype buddy list in this case. >> >> I'd rather split the fix from the refactoring. And maybe my >> description is longer, but easier to understand? (I guess somebody >> else should judge this) > > Your patch is much better to understand than mine. :) > No need to judge from somebody else. > After your patch is merged, I will resubmit these on top of it. Thanks. I'm doing another evaluation focusing on number of unmovable pageblocks as Mel suggested and then resubmit with tracepoint fixed. Vlastimil -- 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