From owner-freebsd-questions@FreeBSD.ORG Sun Jun 24 22:38:12 2012 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id CF01E1065670 for ; Sun, 24 Jun 2012 22:38:12 +0000 (UTC) (envelope-from eam1edward@gmail.com) Received: from mail-pb0-f54.google.com (mail-pb0-f54.google.com [209.85.160.54]) by mx1.freebsd.org (Postfix) with ESMTP id 9D5298FC17 for ; Sun, 24 Jun 2012 22:38:12 +0000 (UTC) Received: by pbbro2 with SMTP id ro2so6162982pbb.13 for ; Sun, 24 Jun 2012 15:38:12 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=message-id:date:from:user-agent:mime-version:to:subject:references :in-reply-to:content-type:content-transfer-encoding; bh=WfQHQ2PW+COjUD83C7+P/87S/ef94dgU4my07TQqT0w=; b=gd+nrzh2YnfNqd3s1AFabFt5L+TZkH2/I6VPZauXi9OWcL47ZBwOYV68LPh2SX1ayO AIoc9j48+0h/JlVaddAuvPCAdVzv5tMPHMZuS2qpvzS6j4tF0v6s6jOQBuIO8imZXiV6 Bru2vlXy+L3heWpRyriFAKiLW1XYca7k+qEmHj6Ul+UUCDchF5q7FwNBmwHpOM1TQr+7 Dd+F2r1Hiob51XyA8ZhkIrA+3fr9ORct2W0xogN0DqRscpsjYFXP9ivC/iQIUGljUx0G +ZBi2aqLr8+AlCT7/lf0/qi+3oUxlW8kckn4IR2/MiOIZZIJiKMn84+Js/r7P1ed7wcR YNtA== Received: by 10.68.134.161 with SMTP id pl1mr1133331pbb.29.1340577492246; Sun, 24 Jun 2012 15:38:12 -0700 (PDT) Received: from localhost.localdomain ([174.134.109.226]) by mx.google.com with ESMTPS id tq4sm6465327pbc.11.2012.06.24.15.38.10 (version=SSLv3 cipher=OTHER); Sun, 24 Jun 2012 15:38:11 -0700 (PDT) Message-ID: <4FE79800.8000200@gmail.com> Date: Sun, 24 Jun 2012 15:43:12 -0700 From: Edward M User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:13.0) Gecko/20120615 Thunderbird/13.0.1 MIME-Version: 1.0 To: Wojciech Puchar , freebsd-questions@freebsd.org References: <20120624001622.17052.qmail@joyce.lan> <4FE6602C.2050800@gmail.com> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: Subject: Re: Is ZFS production ready? 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: Sun, 24 Jun 2012 22:38:12 -0000 On 06/23/2012 10:38 PM, Wojciech Puchar wrote: >> last binary production ready, used version 14; i also found it >> to be stable >> Any opensource zfs pool verisons beyound that, i am not really sure >> about their stablity compared >> to UFS rock solid filesystem. > > No ZFS pool version can be as trusty as UFS because of ZFS on disk > structure that is plain dangerous. > > ZFS use tree-like structure for everything. If upper part of tree is > corrupted, everything below "disappears" and cannot be found. > > Having 2,3 or even 100 copies of metadata doesn't help if you would > have (maybe transient) hardware problem and bad metadata would be > writen 2,3 or even 100 times. with proper checksum of course. > > UFS uses flat structure - inodes in known places. superblocks are used > to find info about placement, and there are many copies of which only > first is updated under normal operation. > > In really unlikely case of all superblocks corrupted just use newfs on > virtual device (may be md) of same size, with same block and fragment > size, and byte per inode, and copy superblock from here. > Dont email me privately. I like ZFS design however i was only questioning v28 stability for production compared to a mature production tested UFS.