From owner-freebsd-current@FreeBSD.ORG Tue Mar 2 21:11:09 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 36D5B16A4CE for ; Tue, 2 Mar 2004 21:11:09 -0800 (PST) Received: from math.uic.edu (galois.math.uic.edu [131.193.178.114]) by mx1.FreeBSD.org (Postfix) with SMTP id A988A43D1F for ; Tue, 2 Mar 2004 21:11:08 -0800 (PST) (envelope-from vladimir@math.uic.edu) Received: (qmail 990 invoked by uid 31415); 3 Mar 2004 05:11:07 -0000 Date: Tue, 2 Mar 2004 23:11:07 -0600 From: Vladimir V Egorin To: freebsd-current@freebsd.org Message-ID: <20040302231107.A964@math.uic.edu> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.2.5i X-Mailman-Approved-At: Wed, 03 Mar 2004 04:46:37 -0800 Subject: debugging lockups 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, 03 Mar 2004 05:11:09 -0000 I have a FreeBSD-current machine with a system built on Feb 26, 2004. The system hangs hard at seemingly random times. It had the same problem in 5.2 and 5.2.1 releases (but not in 4.8-STABLE) I have tried to investigate this further, as described in the FAQ. I have options DDB options BREAK_TO_DEBUGGER set in the kernel config; the problem is that the system doesn't react to keyboard input (ctrl-alt-esc) after the lockup. X is not running. I can reliably reproduce the problem by starting a process that heavily uses disk and memory (e.g. maple computations, or mencoder), and then killing it. The system locks instantly. I don't believe it's a problem with the hardware at this point: I have tried replacing memory in the machine with no luck, and the system is very stable under heavy loads in 4.8-STABLE. Any suggestions on how to proceed? Do you think I would have more luck with a serial console? Thanks, -- Vladimir