From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx149.postini.com [74.125.245.149]) by kanga.kvack.org (Postfix) with SMTP id A4D0F6B0031 for ; Wed, 4 Sep 2013 19:58:37 -0400 (EDT) Message-ID: <5227C928.8080709@redhat.com> Date: Wed, 04 Sep 2013 19:58:32 -0400 From: Rik van Riel MIME-Version: 1.0 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: owner-linux-mm@kvack.org List-ID: To: David Rientjes Cc: Andrew Morton , Mel Gorman , Minchan Kim , linux-kernel@vger.kernel.org, linux-mm@kvack.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 -- 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