{HEAD ~ Application memory} is allocated to the application from {TAIL ~ a shared memory space} within the database management system 
is allocated from
{ HEAD ~ Application memory } is allocated to the application from { TAIL ~ a shared memory space } within the database management system
HEAD HEAD HEAD HEAD HEAD HEAD REL REL OTH OTH OTH REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH