From owner-freebsd-stable@FreeBSD.ORG Tue Mar 5 22:09:39 2013 Return-Path: Delivered-To: freebsd-stable@freebsd.org Received: from mx1.freebsd.org (mx1.FreeBSD.org [8.8.178.115]) by hub.freebsd.org (Postfix) with ESMTP id 7920B1B2 for ; Tue, 5 Mar 2013 22:09:39 +0000 (UTC) (envelope-from jdc@koitsu.org) Received: from qmta05.emeryville.ca.mail.comcast.net (qmta05.emeryville.ca.mail.comcast.net [IPv6:2001:558:fe2d:43:76:96:30:48]) by mx1.freebsd.org (Postfix) with ESMTP id 5DCCBF9B for ; Tue, 5 Mar 2013 22:09:38 +0000 (UTC) Received: from omta10.emeryville.ca.mail.comcast.net ([76.96.30.28]) by qmta05.emeryville.ca.mail.comcast.net with comcast id 7xWM1l0010cQ2SLA5y9d16; Tue, 05 Mar 2013 22:09:37 +0000 Received: from koitsu.strangled.net ([67.180.84.87]) by omta10.emeryville.ca.mail.comcast.net with comcast id 7y9c1l00C1t3BNj8Wy9c6S; Tue, 05 Mar 2013 22:09:36 +0000 Received: by icarus.home.lan (Postfix, from userid 1000) id 348B173A31; Tue, 5 Mar 2013 14:09:36 -0800 (PST) Date: Tue, 5 Mar 2013 14:09:36 -0800 From: Jeremy Chadwick To: Andriy Gapon Subject: Re: ZFS "stalls" -- and maybe we should be talking about defaults? Message-ID: <20130305220936.GA54718@icarus.home.lan> References: <513524B2.6020600@denninger.net> <89680320E0FA4C0A99D522EA2037CE6E@multiplay.co.uk> <20130305050539.GA52821@anubis.morrow.me.uk> <20130305053249.GA38107@icarus.home.lan> <5135D275.3050500@FreeBSD.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <5135D275.3050500@FreeBSD.org> User-Agent: Mutt/1.5.21 (2010-09-15) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=comcast.net; s=q20121106; t=1362521377; bh=9tEkI7sf4HHRtV5mRCQvuEVF4VrOaz8kR3bM7crWW9Q=; h=Received:Received:Received:Date:From:To:Subject:Message-ID: MIME-Version:Content-Type; b=ZLRMo1erUwpejESZPYN4+JxFztsyk69c4v+NWRp2ELXgKmaFiECuQplz/VncioP1s UYIwET1VgF7q7Q6cm/83pEdCiaolcVdBXMsO2nLk7BuMT4fBZ89UdSNLry1x42e83j PnkQj524oarnAaiyneew9wzLT8MCvDVqRnSDEJt9mKq7uSAzK6seSVQnb2AKs0k7H/ DLMIJjbjWHnnvnRJ9Xggthafyfq8Lo7vrHuk0gK8mfLDgunvs2BxwNQbUNTh+xgRJz 5zCWfCNTwpKX21uEcf7g5s8MGFq91A1Jp1tgyiu7z9OoEkM2DJv5hmOaPbJJkQI2I/ Z4kHu5ZKKhvvQ== Cc: freebsd-stable@FreeBSD.org X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 05 Mar 2013 22:09:39 -0000 On Tue, Mar 05, 2013 at 01:09:41PM +0200, Andriy Gapon wrote: > Completely unrelated to the main thread: > > on 05/03/2013 07:32 Jeremy Chadwick said the following: > > That said, I still do not recommend ZFS for a root filesystem > > Why? Too long a history of problems with it and weird edge cases (keep reading); the last thing an administrator wants to deal with is a system where the root filesystem won't mount/can't be used. It makes recovery or problem-solving (i.e. the server is not physically accessible given geographic distances) very difficult. Are there still issues booting from raidzX or stripes or root pools with multiple vdevs? What about with cache or log devices? My point/opinion: UFS for a root filesystem is guaranteed to work without any fiddling about and, barring drive failures or controller issues, is (again, my opinion) a lot more risk-free than ZFS-on-root. I say that knowing lots of people use ZFS-on-root, which is great -- I just wonder how many of them have tested all the crazy scenarios and then tried to boot from things. > > (this biting people still happens even today) > > What exactly? http://lists.freebsd.org/pipermail/freebsd-questions/2013-February/249363.html http://lists.freebsd.org/pipermail/freebsd-questions/2013-February/249387.html http://lists.freebsd.org/pipermail/freebsd-stable/2013-February/072398.html The last one got solved: http://lists.freebsd.org/pipermail/freebsd-stable/2013-February/072406.html http://lists.freebsd.org/pipermail/freebsd-stable/2013-February/072408.html I know factually you're aware of the zpool.cache ordeal (which may or may not be the cause of the issue shown in the 2nd URL above), but my point is that still at this moment in time -- barring someone using a stable/9 ISO for installation -- there still seem to be issues. Things on the mailing lists which go unanswered/never provide closure of this nature are numerous, and that just adds to my concern. > > - Disks are GPT and are *partitioned, and ZFS refers to the partitions > > not the raw disk -- this matters (honest, it really does; the ZFS > > code handles things differently with raw disks) > > Not on FreeBSD as far I can see. My statement comes from here (first line in particular): http://lists.freebsd.org/pipermail/freebsd-questions/2013-January/248697.html If this is wrong/false, then this furthers my point about kernel folks who are in-the-know needing to chime in and help stop the misinformation. The rest of us are just end-users, often misinformed. -- | Jeremy Chadwick jdc@koitsu.org | | UNIX Systems Administrator http://jdc.koitsu.org/ | | Mountain View, CA, US | | Making life hard for others since 1977. PGP 4BD6C0CB |