From owner-freebsd-current@FreeBSD.ORG Tue Dec 2 20:33:11 2008 Return-Path: Delivered-To: freebsd-current@FreeBSD.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 843D4106564A; Tue, 2 Dec 2008 20:33:11 +0000 (UTC) (envelope-from scode@hyperion.scode.org) Received: from hyperion.scode.org (cl-1361.ams-04.nl.sixxs.net [IPv6:2001:960:2:550::2]) by mx1.freebsd.org (Postfix) with ESMTP id 48EB78FC18; Tue, 2 Dec 2008 20:33:11 +0000 (UTC) (envelope-from scode@hyperion.scode.org) Received: by hyperion.scode.org (Postfix, from userid 1001) id 3888E23C45D; Tue, 2 Dec 2008 21:33:09 +0100 (CET) Date: Tue, 2 Dec 2008 21:33:09 +0100 From: Peter Schuller To: Pawel Jakub Dawidek Message-ID: <20081202203308.GA13818@hyperion.scode.org> References: <20081117205526.GC1733@garage.freebsd.pl> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="BXVAT5kNtrzKuDFl" Content-Disposition: inline In-Reply-To: <20081117205526.GC1733@garage.freebsd.pl> User-Agent: Mutt/1.5.18 (2008-05-17) Cc: freebsd-current@FreeBSD.org Subject: Re: HEADS UP: New ZFS in the tree. X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 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, 02 Dec 2008 20:33:11 -0000 --BXVAT5kNtrzKuDFl Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable I just upgraded my workstation to CURRENT for the purpose of testing ZFS. I wanted to report one anomoly that I have seen so far, that I never saw before and that I do not recognize from other posts. I had ktorrent seemingly hang. The process is in state TL, and does not respond to SIGKILL. SIGCONT also has no effect; neither has SIGSTOP followed by SIGCONT. Though I do not know how ktorrent works internally, the typical behavior, and behavior that I saw just prior to this hang, is one of periodically flushing out a lot of (bittorrent, not file system) blocks. This happens to the point that the pool is more or less saturated for the duration of these bursts (when downloading quickly; around 10 MB/sec in this case). So possibly the triggering factor is quick writing of a lot of randomly located blocks in a handful of files. The current kernel has WITNESS/INVARIATNS, but I did not see anyting in dmesg subsequent or just prior to this hang. Both the pool and the file system seem fully functional; this is distinct from the "hang in zfs state" issue that I see every now and then on 7.0 whereby the affect ZFS file systems will be completely inoperable (but not the entire pool). The sources were cvsup:ed late yesterday. The pool consists of two mirrored vdev:s with one hot spare. The on-disk format is 6 (I have not yet upgrade:d the pool nor any file systems). This is on an amd64 dual-core system with 4 GB:s of RAM. No ZFS related loader variables remain in loader.conf (I let it auto-tune the ARC to around 600 MB). The file system on which ktorrent was doing it's bulk I/O has its recordsize set to 8 kb, but is otherwise standard (no compression or funny options). --=20 / Peter Schuller PGP userID: 0xE9758B7D or 'Peter Schuller ' Key retrieval: Send an E-Mail to getpgpkey@scode.org E-Mail: peter.schuller@infidyne.com Web: http://www.scode.org --BXVAT5kNtrzKuDFl Content-Type: application/pgp-signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.9 (FreeBSD) iEYEARECAAYFAkk1m4QACgkQDNor2+l1i321fgCeI3gIhLMr4SjoqqVjfnm/ATuC baoAoIeqEftXjk+AI74IhbygzLTlQEly =jRP0 -----END PGP SIGNATURE----- --BXVAT5kNtrzKuDFl--