(Received: 2019-04-27, Revised: 2019-06-30 , Accepted: 2019-07-22)
In this paper, a packet switch architecture for mesh-connected multiprocessors based on the use of a set of input FIFO buffers and an output register matrix controlled by a novel distributed timing-based scheduling scheme is proposed. Simple static routing is assumed, with each packet split into a set of independently routed w-bit-wide flits. The device achieves at least 78% throughput for uniformly distributed traffic and an asymptotic higher bound of 100%. In contrast to the state-of-the-art VOQ-based switch architectures, the proposed switch is shown to reach its maximum throughput with no internal speedup required and has an order of magnitude lower hardware com- plexity. Compared to existing buffered crossbar non-VOQ switches with typical flit scheduling mechanisms, the proposed device demonstrates slightly higher throughput and substantially shorter delays in some practically im- portant cases.
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