List zfs Filesystems By Creation Date

There are many snapshots in Ubuntu system if using zfs as OS filesystem. In order to remove those old snapshots, need to list them by creation date using following command

zfs list -H -t snapshot -o name -S creation

To remove those old snapshots, for example, the oldest 18 snapshots can following command

zfs list -H -t snapshot -o name -S creation | tail -18 | xargs -n 1 zfs destroy

References

How to delete all but last [n] ZFS snapshots?