Last month I converted my laptop to btrfs to get some experience using this new, still experimental file system. The bugs tell the story:
- #567065: initramfs-tools: avoid mount -t unknown
I provided a patch which has been accepted. The underlying bug in klibc still remains to be fixed (#548047). - #540786: update-grub doesn't work with root fs on btrfs
There are patches, but not acceptably clean ones. (For values of "acceptably clean" that are somehow more important than "it boots", anyway.)
At this point I had a booting, working btrfs system. The bugs seen over the next weeks were strange:
- #567135: python-dbus went missing from python-support directory on upgrade
Was the filesystem losing information? Maybe. - #569058: dbus: helper not setuid; breaks gnome-power-manager
Both the package maintainer and I am fairly sure it's not really a bug in the package. And another btrfs user also saw the problem. - #568908: gnome-terminal: uses iceweasel for urls despite gconf being configured to use chromium
Hard to say if btrfs was really involved since I can't point at a file that was wrong.
In the meantime, I did some initial work toward supporting btrfs in
d-i, writing a basic partman-btrfs. One of the interesting open
questions is how best to use subvolumes to split up a single btrfs
filesystem. If the installer defines the right set of subvolumes, upgrades
to be rolled back, without also rolling back /home and /srv. The
remaining parts needed for d-i to support btrfs are fairly tractable, but
are waiting until root on btrfs is bootable, and until the filesystem is
not experimental.
I gave up on the current experiement when I ran debsums on my laptop. (So
that long thread was good for something!) It didn't find any corrupt
files. But it did find a lot of md5sums files that were missing. Some of
the packages with missing md5sums were upgraded just this week, and the
md5sums files must have gone missing since.
I have not seen anything that I can say with certainty was caused by btrfs, and not by some other cause, but since I can't trust the data on this laptop now (although git tells me everything in my home directory is ok), I'm reinstalling it, and saying aloha to btrfs, for now.
Update: #575891 is a bug in dpkg that affects btrfs, and probably explains all the odd things I saw.