From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wm0-f49.google.com (mail-wm0-f49.google.com [74.125.82.49]) by kanga.kvack.org (Postfix) with ESMTP id 579766B025F for ; Mon, 11 Apr 2016 03:27:06 -0400 (EDT) Received: by mail-wm0-f49.google.com with SMTP id v188so74115640wme.1 for ; Mon, 11 Apr 2016 00:27:06 -0700 (PDT) Received: from mx2.suse.de (mx2.suse.de. [195.135.220.15]) by mx.google.com with ESMTPS id gy10si27329700wjc.115.2016.04.11.00.27.04 for (version=TLS1 cipher=AES128-SHA bits=128/128); Mon, 11 Apr 2016 00:27:05 -0700 (PDT) Subject: Re: [PATCH v2 4/4] mm, compaction: direct freepage allocation for async direct compaction References: <1459414236-9219-1-git-send-email-vbabka@suse.cz> <1459414236-9219-5-git-send-email-vbabka@suse.cz> <20160411071351.GB26116@js1304-P5Q-DELUXE> From: Vlastimil Babka Message-ID: <570B51C6.4050005@suse.cz> Date: Mon, 11 Apr 2016 09:27:02 +0200 MIME-Version: 1.0 In-Reply-To: <20160411071351.GB26116@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 , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Mel Gorman , Rik van Riel , David Rientjes , Minchan Kim , Michal Hocko On 04/11/2016 09:13 AM, Joonsoo Kim wrote: > On Thu, Mar 31, 2016 at 10:50:36AM +0200, Vlastimil Babka wrote: >> The goal of direct compaction is to quickly make a high-order page available >> for the pending allocation. The free page scanner can add significant latency >> when searching for migration targets, although to succeed the compaction, the >> only important limit on the target free pages is that they must not come from >> the same order-aligned block as the migrated pages. > > If we fails migration, free pages will remain and they can interfere > further compaction success because they doesn't come from previous > order-aligned block but can come from next order-aligned block. You > need to free remaining freelist after migration attempt fails? Oh, good point, thanks! -- 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