[arch-general] can't balance full btrfs raid6 filesystem

[Guus Snijders]

Op 22 feb. 2016 19:48 schreef "Jameson" <imntreal at gmail.com>:
>
> On Mon, Feb 22, 2016 at 1:43 PM Leonid Isaev <
leonid.isaev at jila.colorado.edu>
> wrote:
>
> > See this:
> >
> >
http://marc.merlins.org/perso/btrfs/post_2014-05-04_Fixing-Btrfs-Filesystem-Full-Problems.html
> >
> > Basically, when your btrfs is full, just create a loopback device, add
it
> > to
> > the array, rebalance and then remove the device. This is what I had to
do
> > this
> > Sunday :)
> >
>
> I don't know if you saw the beginning of the thread, but what started this
> whole mess was I allowed a raid6 btrfs filesystem to fill up, and couldn't
> balance it even after adding a real disk. (I tried a loopback device
> first.)

Well, it's a bit of a long thread (long messages really), but have you seen
this:
https://mail-archive.com/linux-btrfs@vger.kernel.org/msg50739.html

Looks like the same problem, the advise was there to (temporary) covert to
raid 1, and then back to raid 6. All with the new disk included, of course.

The disadvantage is that it'll probably take quite some time (rebuilding
could be quicker, depending on backup/restore speeds).
The big advantages are that it's basically online and that it keeps some
redundancy intact.

The OP there hasn't posted the final results yet, but it looks quite
promising.

Mvg, Guus