Traffic Control in Wormhole Routing Meshes under Non-Uniform Traffic Patterns

Nonuniform traffic patterns can severely degrade the performance of wormhole-routing mesh networks in multiprocessor systems. For example, under a temporary hot-spot traffic, a saturation tree might build up temporarily within the network resulting in a temporary network overload that will delay messages substantially. To the knowledge of the authors, no mechanisms were proposed in the open literature so far that are able to control (rather than just route) the traffic flow under those traffic scenarios. This paper introduces and studies several channel assignment strategies for wormhole routers using virtual channels. One proposed assignment strategy is able to effectively control the degrading effects of saturation trees on the uniform background traffic under nonuniform traffic patterns that