From owner-freebsd-stable@FreeBSD.ORG Mon Aug 15 12:00:06 2011 Return-Path: Delivered-To: freebsd-stable@FreeBSD.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 4EAF1106566C for ; Mon, 15 Aug 2011 12:00:05 +0000 (UTC) (envelope-from avg@FreeBSD.org) Received: from citadel.icyb.net.ua (citadel.icyb.net.ua [212.40.38.140]) by mx1.freebsd.org (Postfix) with ESMTP id EFE758FC0C for ; Mon, 15 Aug 2011 12:00:04 +0000 (UTC) Received: from odyssey.starpoint.kiev.ua (alpha-e.starpoint.kiev.ua [212.40.38.101]) by citadel.icyb.net.ua (8.8.8p3/ICyb-2.3exp) with ESMTP id PAA12470; Mon, 15 Aug 2011 15:00:00 +0300 (EEST) (envelope-from avg@FreeBSD.org) Message-ID: <4E490A3F.1000205@FreeBSD.org> Date: Mon, 15 Aug 2011 14:59:59 +0300 From: Andriy Gapon User-Agent: Mozilla/5.0 (X11; FreeBSD amd64; rv:5.0) Gecko/20110705 Thunderbird/5.0 MIME-Version: 1.0 To: Steven Hartland References: <47F0D04ADF034695BC8B0AC166553371@multiplay.co.uk><4E4380C0.7070908@FreeBSD.org> <4E43E272.1060204@FreeBSD.org> <62BF25D0ED914876BEE75E2ADF28DDF7@multiplay.co.uk> <4E440865.1040500@FreeBSD.org> <6F08A8DE780545ADB9FA93B0A8AA4DA1@multiplay.co.uk> <4E441314.6060606@FreeBSD.org> <2C4B0D05C8924F24A73B56EA652FA4B0@multiplay.co.uk> <4E48D967.9060804@FreeBSD.org> <9D034F992B064E8092E5D1D249B3E959@multiplay.co.uk> In-Reply-To: <9D034F992B064E8092E5D1D249B3E959@multiplay.co.uk> X-Enigmail-Version: 1.2pre Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: freebsd-stable@FreeBSD.org Subject: Re: debugging frequent kernel panics on 8.2-RELEASE X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 15 Aug 2011 12:00:06 -0000 on 15/08/2011 13:34 Steven Hartland said the following: > ----- Original Message ----- From: "Andriy Gapon" >> I think (not 100% sure) that with DDB in kernel we could get a better backtrace >> here, possibly with pre-dblfault stack frames, because DDB backend is a bit more >> smarter than the trivial stack(9) printer. > > I've added this into the the kernel on my test machine and will try > to get it panic over the next few days. Seems to need a few days on > uptime before the panics start happening. In addition to increasing > KSTACK_PAGES to 12, if you believe this may be stack exhaustion, do > you want me to remove this increase? Yes, I think it would make sense to change KSTACK_PAGES to the default value. But, OTOH, if you can afford to have DDB in a few more machines, then it would be interesting to compare behavior with different stack sizes. BTW, if you don't want your machines to sit at ddb prompt after panic, then you'd also need either KDB_UNATTENDED option or set debug.debugger_on_panic=0. -- Andriy Gapon