Towards optimal adaptive routing in 3D NoC with limited vertical bandwidth

Abstract

3D NoC is one of the most promising technologies that can overcome the performance barrier of traditional multi-core system. While TSV is the most popular method to realize vertical link for 3D IC, it has many fabrication challenges and the number of TSVs can be limited in practice, thereby limiting vertical bandwidth. Some adaptive routing algorithms have been studied to overcome the bandwidth mismatch. However, there has been no previous study on how much improvement can be achieved by such new algorithms. This paper explores 3D NoC's performance upper-bound beyond which we believe no practically realizable algorithm can reach. We also propose a practically realizable algorithm that achieves performance close to the upper-bound.