The distributed system structure contains an address switch, multiple memory subsystems, and multiple master devices, either processors, I/O agents, or coherent memory adapters, organized into a set of {HEAD ~ nodes} supported by {TAIL ~ a node controller} 
The distributed system structure contains an address switch , multiple memory subsystems , and multiple master devices , either processors , I / O agents , or coherent memory adapters , organized into a set of { HEAD ~ nodes } supported by { TAIL ~ a node controller }
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