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A Flit Level Simulator for Wormhole Routing

Denvil Smith
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Abstract

Wormhole routing, the latest switching technique to be utilized by massively parallel computers, enjoys the distinct advantage of a low latency when compared to other switching techniques. This low latency is due to the nearly distance insensitive routing traits in the absence of channel contention. The low latency of wormhole routing brings about a liability of this switching technique, a chance of deadlock. Deadlock is a concern in wormhole routed networks due to the fact a message does not release its allocated resources until all flits of a message have completely traversed the router in which these resources are associated. The deadlock condition is addressed in the routing algorithm. Simulation tools are currently needed that will aid in the size and number of resources necessary to obtain the optimum utilization of network resources for an algorithm. Some of these resources include the topology of the network along with the number of nodes for the topology, the size of the message, and the number and size of buffers at each router.

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Denvil Smith. 1999-04-01. A Flit Level Simulator for Wormhole Routing. https://arxiv.org/abs/cs/9903004

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