From owner-freebsd-stable@FreeBSD.ORG Thu Apr 28 15:32:12 2011 Return-Path: Delivered-To: freebsd-stable@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 9678B106564A for ; Thu, 28 Apr 2011 15:32:12 +0000 (UTC) (envelope-from thomas@ronner.org) Received: from mail.knopje.net (unknown [IPv6:2001:470:1f15:a0::10]) by mx1.freebsd.org (Postfix) with ESMTP id 5A6BD8FC08 for ; Thu, 28 Apr 2011 15:32:12 +0000 (UTC) Received: from localhost (localhost.localdomain [127.0.0.1]) by mail.knopje.net (Postfix) with ESMTP id 4022C38144 for ; Thu, 28 Apr 2011 17:32:11 +0200 (CEST) X-Virus-Scanned: Debian amavisd-new at knopje.net Received: from mail.knopje.net ([127.0.0.1]) by localhost (hal.knopje.net [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id yEPvlbhMZYWp for ; Thu, 28 Apr 2011 17:32:10 +0200 (CEST) Received: from appelflap.local (unknown [IPv6:2001:610:799:0:223:6cff:fe7f:480e]) by mail.knopje.net (Postfix) with ESMTPSA id 6D1D7380C1 for ; Thu, 28 Apr 2011 17:32:10 +0200 (CEST) Message-ID: <4DB9887A.4080109@ronner.org> Date: Thu, 28 Apr 2011 17:32:10 +0200 From: Thomas Ronner User-Agent: Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10.6; en-US; rv:1.9.2.15) Gecko/20110303 Thunderbird/3.1.9 MIME-Version: 1.0 To: freebsd-stable@freebsd.org References: <537A8F4F-A302-40F9-92DF-403388D99B4B@gsoft.com.au> In-Reply-To: <537A8F4F-A302-40F9-92DF-403388D99B4B@gsoft.com.au> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Subject: Re: ZFS vs OSX Time Machine 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: Thu, 28 Apr 2011 15:32:12 -0000 Hi, On 4/28/11 4:03 PM, Daniel O'Connor wrote: > Does anyone else use ZFS to store TM backups? > > I find that whenever my laptop (over wifi!) starts a TM the ZFS machine it's backing up to grinds to a halt.. Other systems streaming stuff over NFS from it also tend to stall.. Are you using zfs compression? If so, try turning that off. I have a pool with a couple of filesystems with gzip-9 compression enabled. Whenever I write (using zfs receive, it is a backup server) to one of those volumes the whole pool stalls with lots of disk activity. Even creating a snapshot on another filesystem within the same pool lasts a couple of minutes. Does anyone know how to make this perform a little better? It's only writing small amounts (70-100 ops/s, 1 MB/s) on an otherwise idle pool. Still the drive leds blink like crazy. One of my two CPU cores is maxed out, the other is idle. I suppose it won't get any faster (it's CPU bound because of the heavy gzip compression), but why is the pool so slow? Is zfs receive using synchonous writes? Sorry for maybe being offtopic :-) Regards, Thomas