The `zpool list` section of the zpool(8) manpage says that the default list of displayed properties is as below:
> The default list is name, size, used, available, fragmentation,
> expandsize, capacity, health, altroot.
This does not seem to be the case. In fact:
# zpool list
NAME SIZE ALLOC FREE EXPANDSZ FRAG CAP DEDUP HEALTH ALTROOT
tank 10.9T 6.05T 4.83T - 29% 55% 1.00x ONLINE -
The Properties section of the same manpage includes the `used` property, but this seems not to be recognised:
# zpool list -o used
bad property list: invalid property 'used'
The usage message produced here indeed doesn't include `used`.
# uname -r
Reported upstream: https://www.illumos.org/issues/8899
That upstream bug is now fixed and should be merged into all supported FreeBSD versions (the property name change was apparently imported back in 10.0):
There is an additional recent upstream commit [f41179bd376293096297cdc1f32e610d44f65c8b] which adds the "checkpoint" property to the default property list, which applies to FreeBSD 11.2+. This change (but not the "used, avail" => "alloc, free" change) *has* been fixed in FreeBSD current r333081, but has not been MFC into stable/11 yet, let along releng/11.2.
Also, the "[-T d|u]" option to "zpool list" is described twice for some reason, both at the beginning and the end of the option descriptions. svn blame shows that r228019 added it to the end of the option descriptions, and then r263459 added it to the beginning (while keeping the copy at the end).
I don't know the preferred FreeBSD style for option ordering, but the upstream man page <https://illumos.org/man/1m/zpool> puts the -T option description in alphabetical order, between -p and -v.