From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx176.postini.com [74.125.245.176]) by kanga.kvack.org (Postfix) with SMTP id C5F736B0125 for ; Mon, 11 Jun 2012 09:35:10 -0400 (EDT) Message-ID: <4FD5F405.9020904@redhat.com> Date: Mon, 11 Jun 2012 09:35:01 -0400 From: Rik van Riel MIME-Version: 1.0 Subject: Re: [PATCH v9] mm: compaction: handle incorrect MIGRATE_UNMOVABLE type pageblocks References: <201206041543.56917.b.zolnierkie@samsung.com> <4FCD18FD.5030307@gmail.com> <4FCD6806.7070609@kernel.org> <4FCD713D.3020100@kernel.org> <4FCD8C99.3010401@gmail.com> <4FCDA1B4.9050301@kernel.org> <20120611130612.GA3030@suse.de> In-Reply-To: <20120611130612.GA3030@suse.de> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Mel Gorman Cc: Minchan Kim , KOSAKI Motohiro , Bartlomiej Zolnierkiewicz , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Hugh Dickins , Linus Torvalds , Kyungmin Park , Marek Szyprowski , Dave Jones , Andrew Morton , Cong Wang , Markus Trippelsdorf On 06/11/2012 09:06 AM, Mel Gorman wrote: > My initial support for this patch was based on an artifical load but one I > felt was plausible to trigger if CMA was being used. In a normal workload > I thought it might be possible to hit if a large process exited freeing > a lot of pagetable pages from MIGRATE_UNMOVABLE blocks at the same time > but that is a little unlikely and a test case would also look very artifical. > > Hence, I believe that if you require a real workload to demonstrate the > benefit of the patch that it will be very difficult to find. The primary > decision is if CMA needs this or not. I was under the impression that it > was a help for CMA allocation success rates but I may be mistaken. If it helps CMA allocation rates, it should also help allocation rates for transparent hugepages. Conveniently, THP allocation rates are already exported in /proc/vmstat. Now all we need is a test load :) -- All rights reversed -- 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