Re: cloning single-device btrfs file system onto multi-device one

[Arne Jansen <sensille@gmx.net>]

On 28.03.2011 15:17, Stephane Chazelas wrote:
> 
> I then did a btrfs fi balance again and let it run through. However here is
> what I get:
> 
> $ df -h /mnt
> Filesystem            Size  Used Avail Use% Mounted on
> /dev/sdb              8.2T  3.5T  3.2T  53% /mnt
> 
> Only 3.2T left. How would I reclaim the missing space?
> 
> $ sudo btrfs fi show
> Label: none  uuid: ...
>         Total devices 3 FS bytes used 3.43TB
>         devid    4 size 2.73TB used 1.17TB path /dev/sdc
>         devid    3 size 2.73TB used 1.17TB path /dev/sdb
>         devid    2 size 2.70TB used 1.14TB path /dev/sda4
> $ sudo btrfs fi df /mnt
> Data, RAID0: total=3.41TB, used=3.41TB
> System, RAID1: total=16.00MB, used=232.00KB
> Metadata, RAID1: total=35.25GB, used=20.55GB
> 
> So that kind of worked but that is of little use to me as 2TB
> kind of disappeared under my feet in the process.
> 
> Any idea, anyone?
> 

This can just be a miscalculation. Can you please send the output
of btrfs-debug-tree -d /dev/sdc? Shouldn't be too long.

Thanks,
Arne