From owner-freebsd-fs@FreeBSD.ORG Thu Dec 30 08:57:27 2010 Return-Path: Delivered-To: freebsd-fs@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 6A111106564A for ; Thu, 30 Dec 2010 08:57:27 +0000 (UTC) (envelope-from marco@tolstoy.tols.org) Received: from tolstoy.tols.org (tolstoy.tols.org [IPv6:2a02:898:0:20::57:1]) by mx1.freebsd.org (Postfix) with ESMTP id F39128FC12 for ; Thu, 30 Dec 2010 08:57:26 +0000 (UTC) Received: from tolstoy.tols.org (localhost [127.0.0.1]) by tolstoy.tols.org (8.14.4/8.14.4) with ESMTP id oBU8vNws038491 for ; Thu, 30 Dec 2010 08:57:23 GMT (envelope-from marco@tolstoy.tols.org) X-Virus-Status: Clean X-Virus-Scanned: clamav-milter 0.96.5 at tolstoy.tols.org Received: (from marco@localhost) by tolstoy.tols.org (8.14.4/8.14.4/Submit) id oBU8vNfr038490 for freebsd-fs@freebsd.org; Thu, 30 Dec 2010 09:57:23 +0100 (CET) (envelope-from marco) Date: Thu, 30 Dec 2010 09:57:23 +0100 From: Marco van Tol To: freebsd-fs@freebsd.org Message-ID: <20101230085723.GA38391@tolstoy.tols.org> Mail-Followup-To: freebsd-fs@freebsd.org References: <4D1BCE34.4090601@nw-ds.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4D1BCE34.4090601@nw-ds.com> User-Agent: Mutt/1.4.2.3i X-Spam-Status: No, score=-2.9 required=5.0 tests=ALL_TRUSTED,BAYES_00 autolearn=ham version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on tolstoy.tols.org Subject: Re: 8.2-RC1 and ZFS X-BeenThere: freebsd-fs@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Filesystems List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 30 Dec 2010 08:57:27 -0000 On Wed, Dec 29, 2010 at 05:11:32PM -0700, David Samms wrote: > I gave ZFS a try again this afternoon and immediately came across what I > would consider a problem. Simply running dd causes such IO contention > that a GUI desktop is unusable and MP3s stop playing. The problem is > very repeatable, just run dd if=/dev/zero of=big bs=1m count=6400 > > System is amd64, source updated Dec 27. Default ZFS parameters. (no > tuning). With the same system but UFS+s dd causes no problems. Check out this mail from Jeremy Chadwick from December 28th in freebsd-stable@. http://docs.freebsd.org/cgi/getmsg.cgi?fetch=312384+0+current/freebsd-stable I think specifically the comments and tweaks regarding vfs.zfs.txg.timeout="5" and vfs.zfs.txg.write_limit_override=1073741824 should be usefull for you. :-) I'm intentionally not touching the subject why you see what you do without tuning. I'm sure there are a great bunch of different situations for which the defaults are the way they are. :-) Marco van Tol -- "Van Duitsers heb je pas gewonnen als ze met de bus de stad uit zijn." - Youp van 't Hek