From owner-freebsd-hackers@freebsd.org Wed Aug 9 09:24:03 2017 Return-Path: Delivered-To: freebsd-hackers@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 2CEE6DC7E56 for ; Wed, 9 Aug 2017 09:24:03 +0000 (UTC) (envelope-from markmi@dsl-only.net) Received: from asp.reflexion.net (outbound-mail-210-90.reflexion.net [208.70.210.90]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id CFEDD6A49F for ; Wed, 9 Aug 2017 09:24:02 +0000 (UTC) (envelope-from markmi@dsl-only.net) Received: (qmail 31591 invoked from network); 9 Aug 2017 09:19:05 -0000 Received: from unknown (HELO mail-cs-02.app.dca.reflexion.local) (10.81.19.2) by 0 (rfx-qmail) with SMTP; 9 Aug 2017 09:19:05 -0000 Received: by mail-cs-02.app.dca.reflexion.local (Reflexion email security v8.40.2) with SMTP; Wed, 09 Aug 2017 05:17:20 -0400 (EDT) Received: (qmail 20517 invoked from network); 9 Aug 2017 09:17:20 -0000 Received: from unknown (HELO iron2.pdx.net) (69.64.224.71) by 0 (rfx-qmail) with (AES256-SHA encrypted) SMTP; 9 Aug 2017 09:17:20 -0000 Received: from [192.168.1.26] (c-76-115-7-162.hsd1.or.comcast.net [76.115.7.162]) by iron2.pdx.net (Postfix) with ESMTPSA id C3D15EC8676; Wed, 9 Aug 2017 02:17:19 -0700 (PDT) Content-Type: text/plain; charset=us-ascii Mime-Version: 1.0 (Mac OS X Mail 10.3 \(3273\)) Subject: Re: Freebsd 11.0 - system freeze on intensive I/O From: Mark Millard In-Reply-To: Date: Wed, 9 Aug 2017 02:17:19 -0700 Cc: freebsd-hackers , Gautam Content-Transfer-Encoding: quoted-printable Message-Id: <10B7A852-29E9-421A-A4C6-8CC21507E201@dsl-only.net> References: To: Gleb Popov <6yearold@gmail.com> X-Mailer: Apple Mail (2.3273) X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 09 Aug 2017 09:24:03 -0000 On 2017-Aug-9, at 1:35 AM, Gleb Popov <6yearold at gmail.com> wrote: > On Wed, Aug 9, 2017 at 10:11 AM, Gautam wrote: >=20 >> Hi, >>=20 >> I raised this topic on freebsd-questions where I suspect a bug caused = due >> to swapfile usage on FreeBSD. >>=20 >> You could read details in the below thread, but summary is that with = using >> a swapfile (not a swap partition) the system freezes on some single = process >> intensive I/O. This is 100% reproducible. >>=20 >> http://marc.info/?l=3Dfreebsd-questions&m=3D150088763825675&w=3D2 >>=20 >> I raised a PR - 220971 ; but there are no backtraces / logs etc. that = could >> possibly help. >>=20 See bugzilla 206048 for some more information: https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=3D206048 >> I would like to help narrow this down, but do not know how. Any = suggestions >> on how to debug a system freeze and what I need to do ? I could then = try to >> reproduce this and collect the needed information - traces etc. It is a long term, known problem, not new with 11.x as I understand. No reasonable fix is known as I understand: it is not a coding error but a design property. >> Thanks, >> Gautam >> _______________________________________________ >> freebsd-hackers@freebsd.org mailing list >> https://lists.freebsd.org/mailman/listinfo/freebsd-hackers >> To unsubscribe, send any mail to = "freebsd-hackers-unsubscribe@freebsd.org" >>=20 >=20 > I also see symptoms you mentioned on my system, but I'm using ZFS. But = my > system is very ancient, so I've been taking it as normal behavior. = Like you > said, intensive disk IO turns OS completely unresponsive, except = pings. =3D=3D=3D Mark Millard markmi at dsl-only.net