Flit ejection in on-chip wormhole-switched networks with virtual channels

Abstract

An ideal it-ejection model is typically assumed in the Literature for wormhole switches with virtual channels. With such a model its are ejected from the network immediately upon reaching their destinations. This achieves optimal performance but is very costly. The required number of sink queues of a switch for absorbing its is p . v, where p is the number of physical channels (PCs) of the switch; v the number of lanes per PC. To achieve cheap silicon implementations, it-ejection solutions must be cost-effective. We present a novel it-ejection model and a variant of it where the required number of sink queues of a switch is p, i.e., independent of v. We evaluate the it-ejection models with uniformly distributed random traffic in a ZD mesh network. Experimental results show that they exhibit good performance in latency and throughput.