From owner-freebsd-stable@FreeBSD.ORG Tue Nov 22 04:39:54 2005 Return-Path: X-Original-To: freebsd-stable@freebsd.org Delivered-To: freebsd-stable@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 2571716A41F for ; Tue, 22 Nov 2005 04:39:54 +0000 (GMT) (envelope-from kris@obsecurity.org) Received: from elvis.mu.org (elvis.mu.org [192.203.228.196]) by mx1.FreeBSD.org (Postfix) with ESMTP id 3F81C43D58 for ; Tue, 22 Nov 2005 04:39:53 +0000 (GMT) (envelope-from kris@obsecurity.org) Received: from obsecurity.dyndns.org (elvis.mu.org [192.203.228.196]) by elvis.mu.org (Postfix) with ESMTP id 1FA421A3C1A; Mon, 21 Nov 2005 20:39:53 -0800 (PST) Received: by obsecurity.dyndns.org (Postfix, from userid 1000) id 5F78951527; Mon, 21 Nov 2005 23:39:52 -0500 (EST) Date: Mon, 21 Nov 2005 23:39:52 -0500 From: Kris Kennaway To: Greg Rivers Message-ID: <20051122043952.GA14168@xor.obsecurity.org> References: <20051121164139.T48994@w10.sac.fedex.com> <20051122021224.GA12402@xor.obsecurity.org> <20051121205535.W32523@nc8000.tharned.org> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="PNTmBPCT7hxwcZjr" Content-Disposition: inline In-Reply-To: <20051121205535.W32523@nc8000.tharned.org> User-Agent: Mutt/1.4.2.1i Cc: freebsd-stable@freebsd.org, Kris Kennaway Subject: Re: Recurring problem: processes block accessing UFS file system X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 22 Nov 2005 04:39:54 -0000 --PNTmBPCT7hxwcZjr Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Mon, Nov 21, 2005 at 09:23:10PM -0600, Greg Rivers wrote: > On Mon, 21 Nov 2005, Kris Kennaway wrote: >=20 > >Looks like a UFS snapshot deadlock. Are you running something like dump= =20 > >-L on this filesystem, or making other use of snapshots? > > >=20 > Indeed I am (dump -L), but as I said (not very clearly, sorry), the=20 > deadlock also occurs under normal operation when no snapshots are running= =20 > or have ever been run since boot. It's just much less frequent in this= =20 > case. Disabling dumps altogether was one of the first things I tried. It may not be the same problem. You should also try to obtain a trace when snapshots are not implicated. 'show lockedvnods' is very important for diagnosing filesystem deadlocks, and 'alltrace' is the easiest way to obtain stack traces for the resulting processes that are holding locks. You'll want to 'set $lines=3D0' and capture the output from the serial console to a file. Kris --PNTmBPCT7hxwcZjr Content-Type: application/pgp-signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.2 (FreeBSD) iD8DBQFDgqEYWry0BWjoQKURAirqAKCzyYZH1aczArEQKm0DmkgvUZTkfQCgzcrI 4qWa914WwTsRi94jf/zFcLU= =m+EA -----END PGP SIGNATURE----- --PNTmBPCT7hxwcZjr--