An “execution server” manages requests from {HEAD ~ client machines} based on {TAIL ~ priorities} assigned to the requests 
based on
An “ execution server ” manages requests from { HEAD ~ client machines } based on { TAIL ~ priorities } assigned to the requests
OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH