From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1762375Ab3IDX6q (ORCPT ); Wed, 4 Sep 2013 19:58:46 -0400 Received: from mx1.redhat.com ([209.132.183.28]:45206 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753612Ab3IDX6m (ORCPT ); Wed, 4 Sep 2013 19:58:42 -0400 Message-ID: <5227C928.8080709@redhat.com> Date: Wed, 04 Sep 2013 19:58:32 -0400 From: Rik van Riel User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130625 Thunderbird/17.0.7 MIME-Version: 1.0 To: David Rientjes CC: Andrew Morton , Mel Gorman , Minchan Kim , linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: Re: [patch] mm, compaction: periodically schedule when freeing pages References: In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 09/04/2013 07:25 PM, David Rientjes wrote: > We've been getting warnings about an excessive amount of time spent > allocating pages for migration during memory compaction without > scheduling. isolate_freepages_block() already periodically checks for > contended locks or the need to schedule, but isolate_freepages() never > does. > > When a zone is massively long and no suitable targets can be found, this > iteration can be quite expensive without ever doing cond_resched(). > > Check periodically for the need to reschedule while the compaction free > scanner iterates. > > Signed-off-by: David Rientjes Reviewed-by: Rik van Riel -- All rights reversed