From owner-freebsd-current@FreeBSD.ORG Wed Jan 28 10:36:40 2004 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 3674716A4CF for ; Wed, 28 Jan 2004 10:36:40 -0800 (PST) Received: from mail2.speakeasy.net (mail2.speakeasy.net [216.254.0.202]) by mx1.FreeBSD.org (Postfix) with ESMTP id D50A343D48 for ; Wed, 28 Jan 2004 10:36:32 -0800 (PST) (envelope-from jhb@FreeBSD.org) Received: (qmail 30697 invoked from network); 28 Jan 2004 18:36:32 -0000 Received: from dsl027-160-063.atl1.dsl.speakeasy.net (HELO server.baldwin.cx) ([216.27.160.63]) (envelope-sender ) encrypted SMTP for ; 28 Jan 2004 18:36:32 -0000 Received: from 10.50.40.205 (gw1.twc.weather.com [216.133.140.1]) by server.baldwin.cx (8.12.10/8.12.10) with ESMTP id i0SIZwM8063934; Wed, 28 Jan 2004 13:36:28 -0500 (EST) (envelope-from jhb@FreeBSD.org) From: John Baldwin To: Peter Losher Date: Wed, 28 Jan 2004 12:43:10 -0500 User-Agent: KMail/1.5.4 References: <20040127082106.L14045@farside.isc.org> <200401271334.07761.jhb@FreeBSD.org> <200401271420.05240.Peter_Losher@isc.org> In-Reply-To: <200401271420.05240.Peter_Losher@isc.org> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200401281243.10655.jhb@FreeBSD.org> X-Spam-Checker-Version: SpamAssassin 2.55 (1.174.2.19-2003-05-19-exp) cc: current@freebsd.org Subject: Re: spin lock panic in 5.2-REL X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 28 Jan 2004 18:36:40 -0000 On Tuesday 27 January 2004 05:19 pm, Peter Losher wrote: > On Tuesday 27 January 2004 10:34 am, John Baldwin wrote: > > This is a very hard to debug problem. If WITNESS is on it provides more > > useful information that can help track that down, but I wouldn't expect a > > production machine to be using WITNESS. > > Yes, I was running a kernel for a short while w/ INVARIANTS and WITNESS, > but it was basically useless after a couple of hours under load under the > giant lock. How much of a performance hit is just WITNESS? A lot. I think Robert Watson has seen as high a performance impact as 40%. -- John Baldwin <>< http://www.FreeBSD.org/~jhb/ "Power Users Use the Power to Serve" = http://www.FreeBSD.org