Process Variation Delay and Congestion Aware Routing Algorithm for Asynchronous NoC Design

Abstract

The effect of process variation (PV) on delay is a major reason to deteriorate the performance in advanced technologies. The performance of different routing algorithms is determined with/without PV for various traffic patterns. The saturation throughput and average message delay are used as performance metrics to evaluate the throughput. PV decreases the saturation throughput and increases the average message delay. PV increases the average message delay by up to 90% and decreases the saturation throughput by up to 29% compared with nominal characteristics of different routing algorithms. Adaptive routing algorithm should be manipulated with the PV. A novel PV delay and congestion aware routing (PDCR) algorithm is proposed for asynchronous network-on-chip design. PDCR is adaptive, low cost, and scalable. The novel routing algorithm outperforms different adaptive routing algorithms in the average delay and saturation throughput for various traffic patterns. PDCR can achieve up to 12%–32% average message delay lower than that of other routing algorithms. Moreover, the proposed scheme yields improvements in saturation throughput by up to 11%–82% compared with other adaptive routing algorithms.