A Bandwidth-Efficient Implementation of Mesh with Multiple Broadcasting

This paper presents a mesh with virtual buses as the bandwidth-efficient implementation of the mesh with multiple broadcasting on which many computational problems can be solved with reduced time complexity. The new system provides a low latency and high bandwidth communication mechanism without the disadvantage of the dual network approach: the possible bandwidth waste. The virtual buses are built using those communication links of the base point-to-point mesh network only upon request. Even if bus requests are not made, the full network bandwidth is harnessed by the point-to-point communication. On the contrary, the bandwidth assigned to the conventional real buses will be wasted when there is little bus request. This paper introduces a wormhole router design equipped with the virtual bus functions, describes the connections among these routers, and presents various virtual bus transactions. We prove the effectiveness of the virtual bus by showing that a representative semigroup computation can be solved very efficiently on it: a vector maxima finding is accelerated by 2.66 times in the experiment. We also explore the network characteristics by the distributiondriven simulation of the system. These evaluations convinced us that the mesh with virtual buses is a promising approach to low latency and high bandwidth communication which has applications in many parallel computations such as in parallel simulations, computer graphics, real time systems, and many others.