Performance and complexity analysis of credit-based end-to-end flow control in network-on-chip

Abstract

Network-on-Chip is an alternative paradigm to improve communication bandwidth compared to bus-based communication, and its performance degrades if there is no effective flow control method. Heterogeneous networks with very slow processing elements especially need a flow control mechanism at the transport layer to prevent too much packet injection. In this thesis, a credit-based end-to-end flow control (CB-EEFC) is implemented to control the network latency at high traffic loads. Simulation in mesh networks shows improved performance in latency and 0.5%~3% saturated throughput decrease with the CB-EEFC method. RTL gate level simulation shows that a network interface using CB-EEFC brings about a 12.9% increase in complexity compared to a network interface without CB-EEFC.