Comment # 8 on bug 1205740 from William Brown

(In reply to Goldwyn Rodrigues from comment #7)
> Subvolumes are not flat but hierarchical. btrfs subvolume list / provides
> you with the information. man btrfs-subvolume also provides you with
> information how subvolumes are defined or managed.
> 
> From the man page of btrfs-balance:
> From kernel 3.3 onwards, btrfs balance can limit its action to a subset
> of the whole filesystem, and can be used to change the replication con-
> figuration (e.g.  moving data from single to RAID1).

The bug still exists though. When I want to act on the "filesystem" as a whole,
I can't because you have to nominate a "subvolume" as the administration point,
which incorrectly returns that you can't modify it. 

Generally, it seems like in this whole topic, that btrfs administration is very
confused and may have a lot of usability traps. I think that needs to be
addressed because not everyone is a btrfs developer like you, and people have
jobs to do, so they need tools that work in predictable and reliable manners.

Just humour me, go install transactional server, and try to make it raid1 with
btrfs and see what the experience is like.