From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pd0-f178.google.com (mail-pd0-f178.google.com [209.85.192.178]) by kanga.kvack.org (Postfix) with ESMTP id 994E96B006E for ; Thu, 8 Jan 2015 03:23:46 -0500 (EST) Received: by mail-pd0-f178.google.com with SMTP id r10so9847533pdi.9 for ; Thu, 08 Jan 2015 00:23:46 -0800 (PST) Received: from lgeamrelo04.lge.com (lgeamrelo04.lge.com. [156.147.1.127]) by mx.google.com with ESMTP id bp4si7316560pdb.100.2015.01.08.00.23.43 for ; Thu, 08 Jan 2015 00:23:45 -0800 (PST) Date: Thu, 8 Jan 2015 17:23:53 +0900 From: Joonsoo Kim Subject: Re: [PATCH 3/3] mm/compaction: add tracepoint to observe behaviour of compaction defer Message-ID: <20150108082353.GE25453@js1304-P5Q-DELUXE> References: <1417593127-6819-1-git-send-email-iamjoonsoo.kim@lge.com> <1417593127-6819-3-git-send-email-iamjoonsoo.kim@lge.com> <54ABC6AF.1020108@suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <54ABC6AF.1020108@suse.cz> Sender: owner-linux-mm@kvack.org List-ID: To: Vlastimil Babka Cc: Andrew Morton , Mel Gorman , David Rientjes , linux-mm@kvack.org, linux-kernel@vger.kernel.org On Tue, Jan 06, 2015 at 12:27:43PM +0100, Vlastimil Babka wrote: > On 12/03/2014 08:52 AM, Joonsoo Kim wrote: > > compaction deferring logic is heavy hammer that block the way to > > the compaction. It doesn't consider overall system state, so it > > could prevent user from doing compaction falsely. In other words, > > even if system has enough range of memory to compact, compaction would be > > skipped due to compaction deferring logic. This patch add new tracepoint > > to understand work of deferring logic. This will also help to check > > compaction success and fail. > > > > Signed-off-by: Joonsoo Kim > > You only call the tracepoints from try_to_compact_pages(), but the corresponding > functions are also called from elsewhere, e.g. kswapd. Shouldn't all be > included? Otherwise one might consider the trace as showing a bug, where the > defer state suddenly changed without being captured in the trace. Yes, I should include all the others. I also have experience of this confusion. 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