def _get_disk_available_least():
    'Return total real disk available least size.\n\n            The size of available disk, when block_migration command given\n            disk_over_commit param is FALSE.\n\n            The size that deducted real instance disk size from the total size\n            of the virtual disk of all instances.\n\n            '
    disk_free_gb = disk_info_dict['free']
    disk_over_committed = self.driver._get_disk_over_committed_size_total()
    available_least = ((disk_free_gb * units.Gi) - disk_over_committed)
    return (available_least / units.Gi)
Return total real disk available least size.

The size of available disk, when block_migration command given
disk_over_commit param is FALSE.

The size that deducted real instance disk size from the total size
of the virtual disk of all instances.
def _get_disk_available_least():
    'Return total real disk available least size.\n\n            The size of available disk, when block_migration command given\n            disk_over_commit param is FALSE.\n\n            The size that deducted real instance disk size from the total size\n            of the virtual disk of all instances.\n\n            '
    disk_free_gb = disk_info_dict['free']
    disk_over_committed = self.driver._get_disk_over_committed_size_total()
    available_least = ((disk_free_gb * units.Gi) - disk_over_committed)
    return (available_least / units.Gi)