From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pg0-f70.google.com (mail-pg0-f70.google.com [74.125.83.70]) by kanga.kvack.org (Postfix) with ESMTP id 6EFCC6B03B2 for ; Fri, 7 Apr 2017 12:58:28 -0400 (EDT) Received: by mail-pg0-f70.google.com with SMTP id x125so78091885pgb.5 for ; Fri, 07 Apr 2017 09:58:28 -0700 (PDT) Received: from mail-pg0-x22b.google.com (mail-pg0-x22b.google.com. [2607:f8b0:400e:c05::22b]) by mx.google.com with ESMTPS id m21si5630661pgh.384.2017.04.07.09.58.27 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 07 Apr 2017 09:58:27 -0700 (PDT) Received: by mail-pg0-x22b.google.com with SMTP id g2so70804705pge.3 for ; Fri, 07 Apr 2017 09:58:27 -0700 (PDT) Date: Fri, 7 Apr 2017 09:58:17 -0700 (PDT) From: Hugh Dickins Subject: Re: Is it safe for kthreadd to drain_all_pages? In-Reply-To: <20170407163932.GJ16413@dhcp22.suse.cz> Message-ID: References: <20170406130614.a6ygueggpwseqysd@techsingularity.net> <20170407163932.GJ16413@dhcp22.suse.cz> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org List-ID: To: Michal Hocko Cc: Hugh Dickins , Andrew Morton , Mel Gorman , Tejun Heo , linux-kernel@vger.kernel.org, linux-mm@kvack.org On Fri, 7 Apr 2017, Michal Hocko wrote: > On Fri 07-04-17 09:25:33, Hugh Dickins wrote: > [...] > > 24 hours so far, and with a clean /var/log/messages. Not conclusive > > yet, and of course I'll leave it running another couple of days, but > > I'm increasingly sure that it works as you intended: I agree that > > > > mm-move-pcp-and-lru-pcp-drainging-into-single-wq.patch > > mm-move-pcp-and-lru-pcp-drainging-into-single-wq-fix.patch > > > > should go to Linus as soon as convenient. Though I think the commit > > message needs something a bit stronger than "Quite annoying though". > > Maybe add a line: > > > > Fixes serious hang under load, observed repeatedly on 4.11-rc. > > Yeah, it is much less theoretical now. I will rephrase and ask Andrew to > update the chagelog and send it to Linus once I've got your final go. I don't know akpm's timetable, but your fix being more than a two-liner, I think it would be better if it could get into rc6, than wait another week for rc7, just in case others then find problems with it. So I think it's safer *not* to wait for my final go, but proceed on the assumption that it will follow a day later. Hugh -- 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