From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail0131.smtp25.com ([75.126.84.131]:58142 "EHLO mail0131.smtp25.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751888AbbJKM3b convert rfc822-to-8bit (ORCPT ); Sun, 11 Oct 2015 08:29:31 -0400 From: covici@ccs.covici.com To: Duncan <1i5t5.duncan@cox.net> cc: linux-btrfs@vger.kernel.org Subject: Re: btrfs says no errors, but booting gives lots of errors In-reply-to: References: <8042.1444481164@ccs.covici.com> <56191CC2.9000505@googlemail.com> <11640.1444488108@ccs.covici.com> <561932EF.2090005@bouton.name> <5619385C.7040103@googlemail.com> <16953.1444496102@ccs.covici.com> <56198B7B.90806@bouton.name> <27402.1444518173@ccs.covici.com> <27611.1444518496@ccs.covici.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Date: Sun, 11 Oct 2015 08:29:27 -0400 Message-ID: <7505.1444566567@ccs.covici.com> Sender: linux-btrfs-owner@vger.kernel.org List-ID: Duncan <1i5t5.duncan@cox.net> wrote: > covici posted on Sat, 10 Oct 2015 19:08:16 -0400 as excerpted: > > > covici@ccs.covici.com wrote: > > > >> Lionel Bouton wrote: > >> > >> > Le 10/10/2015 18:55, covici@ccs.covici.com a écrit : > >> > > [...] > >> > > But do you folks have any idea about my original question, this > >> > > leads me to think that btrfs is too new or something. > >> > > >> > I've seen a recent report of a problem with btrfs-progs 4.2 confirmed > >> > as a bug in mkfs. As you created the filesystem with it, it could be > >> > the problem. > > > > I do have 4.2.2, I could go to, would that be better? > > btrfs-progs-4.2.2 does indeed have the mkfs.btrfs fixes for the bug in > question. You should be fine remaking the filesystem with it. > > If you created the filesystem with the buggy mkfs.btrfs, AFAIK, current > 4.2.2 btrfs check can detect the error, but can't fix it. Blowing away > the filesystem and recreating is the only known fix at this time, and > filesystems created with the buggy version are not safe and could blow up > at any time, so it's best to be rid of them and onto something more > stable as soon as possible. > > I can't help with the subvolumes bit, however, because while I'm on > gentoo/~amd64 here too, also with systemd... > > I don't use subvolumes, as to me it's simply putting too many eggs in one > filesystem basket. Instead, I prefer multiple separate btrfs > filesystems, each on their own partitions. My / includes most of what > packages install, including /usr and /var but not /var/log. It's 8 GiB > in size, under half used. /home is separate, the repos tree (gentoo and > overlays) along with ccache, binpackages, the kernel tree, etc, are > together on a separate partition, /var/log is separate (and tiny, half a > GiB), etc. I keep / mounted read-only by default, so have the parts of / > var/lib that must be runtime-writable symlinked to subdirs of /home/var, > with /home of course mounted writable, but other than that and some /var/ > log/ subdirs, anything that's installed by a package is on /, a lesson I > learned the hard way when I had to recover from backups where /, /usr > and /var were from backups taken on different dates and thus not > synchronized with what portage /thought/ was installed based on /var/db/ > pkg. > > Not saying that's best for you, but it's a solution that I've found works > very well for me, and the relative small 8 GiB size of / makes it easy to > have backup copies of it that I can boot, should my working / take a > dump. But if it's all on the same filesystem, as it is with subvolumes, > and that filesystem takes a dump... it's all gone at once! That's not > something I want to happen, so I vastly prefer the independent > filesystems, but with everything (but the limited exceptions mentioned > above) the package manager deals with on the same one, so it all stays > synced and is backed up as a single unit, which after all remains > reasonably small, 8 GiB, less than half used. Thanks, in the ext4 world, I have lvm and lots of things using separate lvm's. I don't want to go back to partitions, if btrfs is that fragile, maybe I should waita while yet. Or, I could use lvm and put btrfs on top of that, but it seems strange to me. -- Your life is like a penny. You're going to lose it. The question is: How do you spend it? John Covici covici@ccs.covici.com