Performance evaluation of hierarchical ring-based shared memory multiprocessors

Investigates the performance of word-packet, slotted unidirectional ring-based hierarchical direct networks in the context of large-scale shared memory multiprocessors. Slotted unidirectional rings are attractive because their electrical characteristics and simple interfaces allow for fast cycle times and large bandwidths. For large-scale systems, it is necessary to use multiple rings for increased aggregate bandwidth. Hierarchies are attractive because the topology ensures unique paths between nodes, simple node interfaces and simple inter-ring connections. To ensure that a realistic region of the design space is examined, the architecture of the network used in the Hector prototype is adopted as the initial design point. A simulator of that architecture has been developed and validated with measurements from the prototype. The system and workload parameterization reflects conditions expected in the near future. The results of this study shows the importance of system balance on performance