From owner-freebsd-current@FreeBSD.ORG Tue Oct 26 12:01:21 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 2CD5C16A4CE for ; Tue, 26 Oct 2004 12:01:21 +0000 (GMT) Received: from fledge.watson.org (fledge.watson.org [204.156.12.50]) by mx1.FreeBSD.org (Postfix) with ESMTP id CD31643D2F for ; Tue, 26 Oct 2004 12:01:20 +0000 (GMT) (envelope-from robert@fledge.watson.org) Received: from fledge.watson.org (localhost [127.0.0.1]) by fledge.watson.org (8.13.1/8.13.1) with ESMTP id i9QC0pkM029826; Tue, 26 Oct 2004 08:00:51 -0400 (EDT) (envelope-from robert@fledge.watson.org) Received: from localhost (robert@localhost)i9QC0pJT029823; Tue, 26 Oct 2004 13:00:51 +0100 (BST) (envelope-from robert@fledge.watson.org) Date: Tue, 26 Oct 2004 13:00:51 +0100 (BST) From: Robert Watson X-Sender: robert@fledge.watson.org To: =?iso-8859-2?q?S=B3awek_=AFak?= In-Reply-To: <86k6tdeq84.fsf@thirst.unx.era.pl> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=ISO-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE cc: current@freebsd.org Subject: Re: Hard hangs on AMD64 with mpsafenet enabled 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: Tue, 26 Oct 2004 12:01:21 -0000 Thanks for the report -- I have some questions below that it would be helpful if you could answer. On Tue, 26 Oct 2004, [iso-8859-2] S=B3awek =AFak wrote: > I've got a Sun V20z 2 cpu Opteron box. I experience hard hangs when > accessing NFS simulatneously from 2 processes (tested with parallel p= ort > builds with /usr/ports mounted over NFS with > nosuid,nodev,soft,bg,intr). rpc.lockd and rpc.statd are both enabled = for > NFS. From=20the above, can I assume that this is a problem on the NFS client, an= d that the NFS server is on another system reachable via a local area network? When "hung", can the machine be pinged from another machine? From=20your subject line, it looks like you mean "when debug.mpsafenet=3D0, this doesn't happen". Is that a correct reading? Could you try running with WITNESS and INVARIANTS enabled, and see if you get any specific warnings or assertion failures? A hard hang could imply a deadlock, which WITNESS would be able to report on. Other sources of hard hangs may be easier to debug with INVARIANTS and WITNESS enabled. If possible, getting access to a serial console might make this problem significantly easier to debug. > I cannot also enter the debugger with C-M-ESC (no serial console at t= his > moment, sorry). When the system is running and I try to enter the deb= ugger > on video console I get garbage on the screen and a reboot immediately > after. Scary stuff. I can't play with MP watchdog now (4 CPU box arri= ves in > two weeks). So when there isn't a problem and you try to enter the debugger on the video console, you get the garbage, or only when this problem is manifesting?=20 Thanks, Robert N M Watson FreeBSD Core Team, TrustedBSD Projects robert@fledge.watson.org Principal Research Scientist, McAfee Research