From owner-freebsd-hackers@FreeBSD.ORG Tue Jun 9 17:21:44 2009 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 85EC31065670; Tue, 9 Jun 2009 17:21:44 +0000 (UTC) (envelope-from snb@freebsd.org) Received: from freefall.freebsd.org (freefall.freebsd.org [IPv6:2001:4f8:fff6::28]) by mx1.freebsd.org (Postfix) with ESMTP id 7216C8FC1B; Tue, 9 Jun 2009 17:21:44 +0000 (UTC) (envelope-from snb@freebsd.org) Received: from ebi.local (root@localhost [127.0.0.1]) by freefall.freebsd.org (8.14.3/8.14.3) with ESMTP id n59HLgu6088110; Tue, 9 Jun 2009 17:21:43 GMT (envelope-from snb@freebsd.org) Date: Tue, 9 Jun 2009 19:21:42 +0200 From: Nick Barkas To: Dan Naumov Message-ID: <20090609172142.GA92146@ebi.local> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.19 (2009-01-05) Cc: freebsd-hackers@freebsd.org, freebsd-current@freebsd.org Subject: Re: sysinstall, GJOURNAL and ZFS X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 09 Jun 2009 17:21:45 -0000 On Tue, Jun 09, 2009 at 04:57:30PM +0200, Dan Naumov wrote: > > UFS2+SoftUpdates works fine on properly configured UFS2 - and very fast. > Yes, UFS2+SoftUpdates is very fast, however, in the case of a power > loss or having to pull the plug on a locked up system, it has a > noticeably higher chance of leaving you with an unbootable system than > if you were using Linux with ext3/ext4 or Windows with NTFS. Can you back this up? I cannot recall having ever rendered a FreeBSD system unbootable due to UFS/UFS2 problems after a power failure or crash. I once had a problem with snapshots that made background fsck fail and crash the system, but it was fixable by booting single user and running fsck manually. This was a couple of years ago, and I think the problem has since been fixed. ZFS at least probably is not able to replace UFS2 for everyone, at this time, anyway. Perhaps gjournal can be a replacement for softupdates for many people who do still need UFS2, but I'm not sure. I think in any case, any existing bugs that cause UFS2+softupdates to catastrophically fail in the event of power failures or system crashes need to be fixed. Making it easier for users to install a system with ZFS or gjournal does nothing for those who have existing systems with UFS2+softupdates, and those who cannot use ZFS or gjournal in the near future for whatever reason. That being said, I do agree that being able to support ZFS and gjournal in sysinstall or an alternative installer would be great. Nick