From owner-freebsd-hackers@FreeBSD.ORG Wed Jul 10 18:57:19 2013 Return-Path: Delivered-To: hackers@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by hub.freebsd.org (Postfix) with ESMTP id 15E95E4 for ; Wed, 10 Jul 2013 18:57:19 +0000 (UTC) (envelope-from jkh@mail.turbofuzz.com) Received: from mail.crittercasa.com (mail.turbofuzz.com [208.87.221.144]) by mx1.freebsd.org (Postfix) with ESMTP id EADA9147C for ; Wed, 10 Jul 2013 18:57:18 +0000 (UTC) Received: from [10.20.30.145] (75-101-82-48.static.sonic.net [75.101.82.48]) (using TLSv1 with cipher AES128-SHA (128/128 bits)) (No client certificate requested) by mail.crittercasa.com (Postfix) with ESMTPS id 55C61164896; Wed, 10 Jul 2013 11:55:11 -0700 (PDT) Mime-Version: 1.0 (Mac OS X Mail 6.5 \(1508\)) Subject: Kernel dumps [was Re: possible changes from Panzura] From: Jordan Hubbard In-Reply-To: Date: Wed, 10 Jul 2013 11:57:10 -0700 Message-Id: <9890DFF1-892A-4DCA-9E33-B70681154F43@mail.turbofuzz.com> References: To: Julian Elischer X-Mailer: Apple Mail (2.1508) X-Mailman-Approved-At: Wed, 10 Jul 2013 19:54:52 +0000 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: quoted-printable X-Content-Filtered-By: Mailman/MimeDel 2.1.14 Cc: hackers@freebsd.org X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 10 Jul 2013 18:57:19 -0000 On Jul 10, 2013, at 11:16 AM, Julian Elischer = wrote: > My first candidates are: Those sound useful. Just out of curiosity, however, since we're on the = topic of kernel dumps: Has anyone even looked into the notion of an = emergency fall-back network stack to enable remote kernel panic (or = system hang) debugging, the way OS X lets you do? I can't tell you the = number of times I've NMI'd a Mac and connected to it remotely in a = scenario where everything was totally wedged and just a couple of = minutes in kgdb (or now lldb) quickly showed that everything was waiting = on a specific lock and the problem became manifestly clear. The feature also lets you scrape a panic'd machine with automation, = running some kgdb scripts against it to glean useful information for = later analysis vs having to have someone schlep the dump image manually = to triage. It's going to be damn hard to live without this now, and if = someone else isn't working on it, that's good to know too! - Jordan