Transport-layer assisted vertical traffic balanced routing for thermal-aware three-dimensional Network-on-Chip systems

The thermal problem of three-dimensional Network-on-Chip (3D NoC) is severer than 2D NoC because chip stacking. To keep the temperature below a certain thermal limit, the near-overheat routers are throttled and the 3D topology becomes Non-Stationary Irregular Mesh (NSI-Mesh). To ensure the successful packet delivery in the NSI-Mesh, Transport Layer Assisted Routing (TLAR) scheme was proposed. It has better performance than the conventional routing approaches for NSI-Mesh. However, it still suffers significant traffic congestion in the bottom chip layer and extremely traffic unbalance between vertical chip layers. In this paper, we propose a transport layer assisted Vertical Traffic Balance Routing (VTBR) scheme. It can be applied to any routing approaches for NSI-Mesh. The experimental results show that the proposed VTBR can achieve more balanced traffic in the vertical direction and improve 35.3% ~ 40% network throughput.