From owner-freebsd-hackers@FreeBSD.ORG Wed Jul 16 05:57:45 2003 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id E276937B401 for ; Wed, 16 Jul 2003 05:57:45 -0700 (PDT) Received: from mail.silverwraith.com (66-214-182-79.la-cbi.charterpipeline.net [66.214.182.79]) by mx1.FreeBSD.org (Postfix) with ESMTP id 0DA6143FCB for ; Wed, 16 Jul 2003 05:57:45 -0700 (PDT) (envelope-from avleen@silverwraith.com) Received: from avleen by mail.silverwraith.com with local (Exim 4.20) id 19clqq-000C0i-Lw for freebsd-hackers@freebsd.org; Wed, 16 Jul 2003 05:57:44 -0700 Date: Wed, 16 Jul 2003 05:57:44 -0700 From: Avleen Vig To: freebsd-hackers@freebsd.org Message-ID: <20030716125744.GI68950@silverwraith.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.4i Sender: Avleen Vig Subject: Re: 4.8 panic "ffs_clusteralloc: map mismatch" X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 16 Jul 2003 12:57:46 -0000 > I have been experiencing several "ffs_clusteralloc: map mismatch" > kernel panics (always while heavy r/w activity on ad0). PC in question > has SuperMicro P3TDL3 motherboard, > 2 ide + 1 scsi HDD and 4 nics (full dmesg & kernel config attached). Andrew, I spend about two to three years fighting with a system trying to figure out what was wrong, and why these errors were caused. I got the very same crashes you're seeing now. I'm sure others are too, and I think this reply would be useful for the archives. My Solution: I eventually realised that my problem was with one of three things: 1) bit flips in main memory 2) bit flips in cache 3) bad hard drive I replaced all of the memory after a few months. The problems stopped for a few weeks but quickly returned. So I don't think it was main memory, unless the new set or the sockets were damaged. I couldn't replace the cache because I couldn't find any more. The system was an old P1 (originally 75Mhz). This could have been the problem. I did once try turning off L2 cache in the BIOS, and I think the crashes *might* have continued. So it's possible the problems were here. Finally I didn't replace the hard drive, but I did find that moving load off the original drive to a second drive helpped reduce the number of crashes, although they still continued to happen. HTH. -- Avleen Vig "Say no to cheese-eating surrender-monkeys" Systems Admin "Fast, Good, Cheap. Pick any two." www.silverwraith.com "Move BSD. For great justice!"