monitoring whether currently utilized performance capabilities of {HEAD ~ each} of {TAIL ~ the storage arrays} are within a predetermined range of maximum performance capabilities for the storage arrays; and 
monitoring whether currently utilized performance capabilities of { HEAD ~ each } of { TAIL ~ the storage arrays } are within a predetermined range of maximum performance capabilities for the storage arrays ; and
OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH