A NEW DEADLOCK PREVENTION SCHEME FOR NONMINIMAL ADAPTIVE WORMHOLE ROUTING

Abstract

In multicomputer networks, the adaptive routing has been expected as a promising way to improve network performance by utilizing available network bandwidth. Previous adaptive routing algorithms in wormhole-routed multicomputer networks restrict the routing of messages to prevent deadlocks, and the routing restriction results in low degree of adaptiveness and low utilization of communication channels. In this paper, we examine the possibility of performing restriction-free, nonminimal adaptive routing in wormhole-routed networks as an approach to further improving the performance of these networks. A new flow control policy, called message cutting, is proposed, and two adaptive routing strategies are presented. Freedom of communication deadlock is achieved by the proposed flow control policy. The proposed adaptive routing strategies do not restrict routing and maximally utilize the physical and virtual channels. Simulation results show that the restriction-free adaptive routing approach is promising from the fact that it has the lowest latency and highest throughput depending on the number of virtual channels per physical channel and patterns of message traffic.