From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752447AbdB1Ol1 (ORCPT ); Tue, 28 Feb 2017 09:41:27 -0500 Received: from mx2.suse.de ([195.135.220.15]:36399 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751441AbdB1OlT (ORCPT ); Tue, 28 Feb 2017 09:41:19 -0500 Date: Tue, 28 Feb 2017 15:40:46 +0100 From: Michal Hocko To: Robert Kudyba Cc: linux-kernel@vger.kernel.org Subject: Re: rsync: page allocation stalls in kernel 4.9.10 to a VessRAID NAS Message-ID: <20170228144045.GD26792@dhcp22.suse.cz> References: <20170228141520.GA28139@dhcp22.suse.cz> <40F07E96-7468-4355-B8EA-4B42F575ACAB@fordham.edu> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <40F07E96-7468-4355-B8EA-4B42F575ACAB@fordham.edu> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue 28-02-17 09:33:49, Robert Kudyba wrote: > > > On Feb 28, 2017, at 9:15 AM, Michal Hocko wrote: > > and this one is hitting the min watermark while there is not really > > much to reclaim. Only the page cache which might be pinned and not > > reclaimable from this context because this is GFP_NOFS request. It is > > not all that surprising the reclaim context fights to get some memory. > > There is a huge amount of the reclaimable slab which probably just makes > > a slow progress. > > > > That is not something completely surprsing on 32b system I am afraid. > > > > Btw. is the stall repeating with the increased time or it gets resolved > > eventually? > > Yes and if you mean by repeating it’s not only affecting rsync but > you can see just now automount and NetworkManager get these page > allocation stalls and kswapd0 is getting heavy CPU load, are there any > other settings I can adjust? None that I am aware of. You might want to talk to FS guys, maybe they can figure out who is pinning file pages so that they cannot be reclaimed. They do not seem to be dirty or under writeback. It would be also interesting to see whether that is a regression. The warning is relatively new so you might have had this problem before just haven't noticed it. -- Michal Hocko SUSE Labs