Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752762AbbD0II4 (ORCPT ); Mon, 27 Apr 2015 04:08:56 -0400 Received: from cantor2.suse.de ([195.135.220.15]:33873 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751915AbbD0IIy (ORCPT ); Mon, 27 Apr 2015 04:08:54 -0400 Date: Mon, 27 Apr 2015 09:08:50 +0100 From: Mel Gorman To: Joonsoo Kim Cc: Andrew Morton , linux-kernel@vger.kernel.org, linux-mm@kvack.org, Vlastimil Babka , Johannes Weiner , Rik van Riel Subject: Re: [PATCH 1/3] mm/page_alloc: don't break highest order freepage if steal Message-ID: <20150427080850.GF2449@suse.de> References: <1430119421-13536-1-git-send-email-iamjoonsoo.kim@lge.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-15 Content-Disposition: inline In-Reply-To: <1430119421-13536-1-git-send-email-iamjoonsoo.kim@lge.com> 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 Content-Length: 801 Lines: 19 On Mon, Apr 27, 2015 at 04:23:39PM +0900, Joonsoo Kim wrote: > When we steal whole pageblock, we don't need to break highest order > freepage. Perhaps, there is small order freepage so we can use it. > The reason why the largest block is taken is to reduce the probability there will be another fallback event in the near future. Early on, there were a lot of tests conducted to measure the number of external fragmenting events and take steps to reduce them. Stealing the largest highest order freepage was one of those steps. -- Mel Gorman SUSE Labs -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/