From owner-freebsd-questions@FreeBSD.ORG Sat Nov 19 18:32:43 2005 Return-Path: X-Original-To: freebsd-questions@freebsd.org Delivered-To: freebsd-questions@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 36B0C16A41F for ; Sat, 19 Nov 2005 18:32:43 +0000 (GMT) (envelope-from dgl@kirk.dlee.org) Received: from sccrmhc13.comcast.net (sccrmhc13.comcast.net [63.240.77.83]) by mx1.FreeBSD.org (Postfix) with ESMTP id B325B43D70 for ; Sat, 19 Nov 2005 18:32:41 +0000 (GMT) (envelope-from dgl@kirk.dlee.org) Received: from kirk.dlee.org ([69.143.16.144]) by comcast.net (sccrmhc13) with ESMTP id <20051119183240013003d190e>; Sat, 19 Nov 2005 18:32:40 +0000 Received: from kirk.dlee.org (dgl@localhost.dlee.org [127.0.0.1]) by kirk.dlee.org (8.12.11/8.12.11) with ESMTP id jAJIWbFP001190 for ; Sat, 19 Nov 2005 13:32:37 -0500 (EST) (envelope-from dgl@kirk.dlee.org) Received: (from dgl@localhost) by kirk.dlee.org (8.12.11/8.12.11/Submit) id jAJIWaVE001189 for freebsd-questions@freebsd.org; Sat, 19 Nov 2005 13:32:36 -0500 (EST) (envelope-from dgl) Date: Sat, 19 Nov 2005 13:32:36 -0500 From: Doug Lee To: freebsd-questions@freebsd.org Message-ID: <20051119183236.GA1042@kirk.dlee.org> Mail-Followup-To: Doug Lee , freebsd-questions@freebsd.org Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Organization: SSB + BART Group User-Agent: Mutt/1.5.9i Subject: deadlock caused by idprio? X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 19 Nov 2005 18:32:43 -0000 I just ran a MySQL lookup process (written in Perl) as root prefixed with "idprio 1." I expected it to take a while, but not several minutes. After a while I decided to abort it, so I typed ^c in its `screen' window. From then on (either from the ^c point or the idprio run, I know not which), I could not create any new processes, nor could I kill the running task. Any attempt to do either would hang indefinitely. I could end processes and work within existing processes as long as they didn't try to create new ones. I entered the debugger (I use the alt method of ~^b) and typed, among other things, "show lockedvnodes" and got one vnode which said "... with 22 pending," and this count went up by 1 each time I tried creating a new process. Sadly, I forgot to snapshot that screen, so I can't quote the rest of that entry. I remember it said VDIR and type something+VOBJECT, but I don't remember what the something was. Unable to retrieve my system, I finally typed "panic" in the debugger so at least the disks would sync. Other than "giving up on 4 buffers," that went fine. Any ideas what this is, and whether it's a bug? I thought idprio was harmless as far as affecting other processes. uname -a: FreeBSD kirk.dlee.org 4.10-STABLE FreeBSD 4.10-STABLE #0: Sun Aug 8 03:03:49 EDT 2004 dgl@kirk.dlee.org:/usr2/obj/usr/src/sys/CUSTOM i386 -- Doug Lee dgl@dlee.org SSB + BART Group doug@bartsite.com http://www.bartsite.com "Is your cucumber bitter? Throw it away. Are there briars in your path? Turn aside. That is enough. Do not go on to say, `Why were things of this sort ever brought into the world?'" --Marcus Aurelius