VmwareContext context = getServiceContext();
VmwareHypervisorHost hyperHost = getHyperHost(context);
ManagedObjectReference morDs = HypervisorHostHelper.findDatastoreWithBackwardsCompatibility(hyperHost, cmd.getStorageId());
if (morDs != null) {
DatastoreMO datastoreMo = new DatastoreMO(context, morDs);
DatastoreSummary summary = datastoreMo.getSummary();
assert (summary != null);
long capacity = summary.getCapacity();
long free = summary.getFreeSpace();
long used = capacity - free;