# zfs list -o space
NAME                              AVAIL   USED  USEDSNAP  USEDDS  USEDREFRESERV  USEDCHILD
srv                               5.81T  2.09T         0     96K              0      2.09T
srv/mirror                        5.81T  1.25T         0     96K              0      1.25T
srv/mirror/cdimage                5.81T  19.7G         0   19.7G              0          0
srv/mirror/ubuntu                 5.81T  1.23T      124G   1.11T              0          0
srv/trees                         5.81T   804G         0    258M              0       804G
srv/trees/linux                   5.81T   406M         0    406M              0          0
srv/trees/ubuntu                   733G   803G         0     96K              0       803G
srv/trees/ubuntu/main              733G   235G         0    235G              0          0
srv/trees/ubuntu/multiverse        733G  54.5G         0   54.5G              0          0
srv/trees/ubuntu/restricted        733G  15.4G         0   15.4G              0          0
srv/trees/ubuntu/universe          733G   499G         0    499G              0          0