From owner-freebsd-current@FreeBSD.ORG Thu Aug 26 18:38:35 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 20CDE16A4CE for ; Thu, 26 Aug 2004 18:38:35 +0000 (GMT) Received: from smtp005.bizmail.sc5.yahoo.com (smtp005.bizmail.sc5.yahoo.com [66.163.175.82]) by mx1.FreeBSD.org (Postfix) with SMTP id 1252D43D39 for ; Thu, 26 Aug 2004 18:38:35 +0000 (GMT) (envelope-from noackjr@alumni.rice.edu) Received: from unknown (HELO optimator.noacks.org) (noackjr@supercrime.org@70.240.199.245 with login) by smtp005.bizmail.sc5.yahoo.com with SMTP; 26 Aug 2004 18:38:34 -0000 Received: from localhost (localhost [127.0.0.1]) by optimator.noacks.org (Postfix) with ESMTP id CCACB6193; Thu, 26 Aug 2004 13:38:33 -0500 (CDT) Received: from optimator.noacks.org ([127.0.0.1]) by localhost (optimator.noacks.org [127.0.0.1]) (amavisd-new, port 10024) with LMTP id 04259-04; Thu, 26 Aug 2004 13:38:32 -0500 (CDT) Received: from www.noacks.org (localhost [127.0.0.1]) by optimator.noacks.org (Postfix) with ESMTP id D35BE610C; Thu, 26 Aug 2004 13:38:31 -0500 (CDT) Received: from 69.53.57.66 (SquirrelMail authenticated user noackjr); by www.noacks.org with HTTP; Thu, 26 Aug 2004 13:38:31 -0500 (CDT) Message-ID: <45273.69.53.57.66.1093545511.squirrel@69.53.57.66> In-Reply-To: <20040826110701.L37301@carver.gumbysoft.com> References: <20040826110701.L37301@carver.gumbysoft.com> Date: Thu, 26 Aug 2004 13:38:31 -0500 (CDT) From: "Jon Noack" To: "Doug White" User-Agent: SquirrelMail/1.4.3a X-Mailer: SquirrelMail/1.4.3a MIME-Version: 1.0 Content-Type: text/plain;charset=iso-8859-1 Content-Transfer-Encoding: 8bit X-Priority: 3 (Normal) Importance: Normal X-Virus-Scanned: by amavisd-new at noacks.org cc: Vinod Kashyap cc: current@freebsd.org Subject: RE: Giant deadlock related to twe X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list Reply-To: noackjr@alumni.rice.edu List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 26 Aug 2004 18:38:35 -0000 Doug White wrote: > On Mon, 23 Aug 2004, Vinod Kashyap wrote: >>> Just got this on my amd64 box. A disk flaked out in my machine, which >>> has a 3ware 8006-2LP with 2 80GB drives in a RAID0. My X session locked >>> up and was able to break to ddb. Some ddb twiddling follows. It looks >>> like, at first glance, some sort of deadlock against softupdates. >>> >>> >> >> The messages indicate timeouts due to the drive continuously returning >> BUSY to the firmware on the controller. This could be caused by the >> the drive going bad, or even a one time disturbance like tugging of >> cables, etc. > > Right, and a failing drive it was, but it shouldn't lock up the entire > system when it happens. Why not? If the drive is continuously returning BUSY, wouldn't the requests just keep getting retried and a process just wait for them to successfully complete? To the user, this would manifest itself as a lockup because the process would block. X and company do a lot of reading/writing of temporary files, so what you are seeing makes sense to me. I see a similar lockup when the NFS server hosting my home directory goes down (SMP -CURRENT so it's been a bit exciting lately...). As soon as the NFS server comes back up X jumps to life again. Jon