From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751187AbcFWOGP (ORCPT ); Thu, 23 Jun 2016 10:06:15 -0400 Received: from mx2.suse.de ([195.135.220.15]:60015 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750729AbcFWOGN (ORCPT ); Thu, 23 Jun 2016 10:06:13 -0400 Subject: Re: [PATCH 19/27] mm: Move vmscan writes and file write accounting to the node To: Mel Gorman , Michal Hocko References: <1466518566-30034-1-git-send-email-mgorman@techsingularity.net> <1466518566-30034-20-git-send-email-mgorman@techsingularity.net> <20160622144039.GG7527@dhcp22.suse.cz> <20160623135758.GY1868@techsingularity.net> Cc: Andrew Morton , Linux-MM , Rik van Riel , Johannes Weiner , LKML From: Vlastimil Babka Message-ID: <9a439cbd-6bdc-3c7b-0327-df3b60cdeff8@suse.cz> Date: Thu, 23 Jun 2016 16:06:09 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.1.1 MIME-Version: 1.0 In-Reply-To: <20160623135758.GY1868@techsingularity.net> Content-Type: text/plain; charset=iso-8859-15; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 06/23/2016 03:57 PM, Mel Gorman wrote: > On Wed, Jun 22, 2016 at 04:40:39PM +0200, Michal Hocko wrote: >> On Tue 21-06-16 15:15:58, Mel Gorman wrote: >>> As reclaim is now node-based, it follows that page write activity >>> due to page reclaim should also be accounted for on the node. For >>> consistency, also account page writes and page dirtying on a per-node >>> basis. >>> >>> After this patch, there are a few remaining zone counters that may >>> appear strange but are fine. NUMA stats are still per-zone as this is a >>> user-space interface that tools consume. NR_MLOCK, NR_SLAB_*, NR_PAGETABLE, >>> NR_KERNEL_STACK and NR_BOUNCE are all allocations that potentially pin >>> low memory and cannot trivially be reclaimed on demand. This information >>> is still useful for debugging a page allocation failure warning. >> >> As I've said in other patch. I think we will need to provide >> /proc/nodeinfo to fill the gap. >> > > I added a patch on top that prints the node stats in zoneinfo but only > once for the first populated zone in a node. Doing this or creating a > new file are both potentially surprising but extending zoneinfo means > there is a greater chance that a user will spot the change. BTW, there should already be /sys/devices/system/node/nodeX/vmstat providing the per-node stats, right? Changing zoneinfo so that some zones have some stats that others don't seems to me like it can break some scripts...