A Demand-Aware Predictive Dynamic Bandwidth Allocation Mechanism for Wireless Network-on-Chip

Abstract

Long distance data communication over multi-hop wireline paths in conventional Networks-on-Chips (NoCs) cause high energy consumption and degradation in bandwidth. Wireless interconnects in the millimeter-wave band have emerged as an energy-efficient interconnection paradigm for multi-core chips interconnected with NoCs. However, spatial variations in traffic distribution and temporal variations in workloads can exert variable bandwidth demands on the NoC fabric. Wireless interconnects which do not require a physical layout of interconnects can be utilized to mitigate this issue. In order to dynamically allocate variable bandwidth to the wireless transceivers depending on the demand, the design of a dynamic and efficient Medium Access Control (MAC) mechanism to grant access to the on-chip wireless communication channel is needed. In this paper, a history based predictor, which can predict the bandwidth demand of the wireless nodes in the wireless NoC is designed. Based on these predicted demands we propose the design of two MAC mechanisms that are able to dynamically allocate bandwidth to the wireless transceivers. Through system level simulations, we show that the demand-aware MAC mechanisms are more energy efficient as well as capable of sustaining higher data bandwidth in wireless NoCs.