btrfs fi usage

root@box:~# btrfs fi usage /mnt/something/
Overall:
    Device size:      14.00TiB
    Device allocated:        13.95TiB
    Device unallocated:      60.02GiB
    Device missing:          0.00B
    Used:             13.92TiB
    Free (estimated):        79.91GiB   (min: 49.90GiB)
    Data ratio:           1.00
    Metadata ratio:           2.00
    Global reserve:      512.00MiB   (used: 0.00B)

Data,single: Size:13.86TiB, Used:13.85TiB (99.86%)
   /dev/mapper/something    13.86TiB

Metadata,DUP: Size:41.50GiB, Used:40.99GiB (98.76%)
   /dev/mapper/something    83.00GiB

System,RAID1: Size:32.00MiB, Used:1.47MiB (4.59%)
   /dev/mapper/something    32.00MiB
   /dev/loop20    32.00MiB

Unallocated:
   /dev/mapper/something    55.05GiB
   /dev/loop20     4.97GiB