Low-cost and low-power unidirectional torus network-on-chip with corner buffer power-gating

ABSTRACT

Network-on-chip (NoC) is one of critical communication architectures for the scaling of future many-core processors. The challenge for on-chip network is reducing design complexity to save both area and power while providing high performance such as low latency and high throughput. Especially, with increase of network size, both design complexity and power consumption have become the bottlenecks preventing proper network scaling. Moreover, as technology continuously scales down, leakage power takes up a larger fraction of total NoC power. It is increasingly important for a power-efficient NoC design to reduce the increasing leakage power. Power-gating, as a representative low-power technique, can be applied to an on-chip network for mitigating leakage power. In this paper, we propose a low-cost and low-power router architecture for the unidirectional torus network, and adopt an improved corner buffer structure for the inoffensive power-gating, which has minimal impact on network performance. Besides, an explicit starvation avoidance mechanism is introduced to guarantee injection fairness while decreasing its negative impact on network throughput. Simulation results with synthetic traffic show that our design can improve network throughput by 11.3% on average and achieve significant power-saving in low- and medium-load regions. In the SPLASH-2 workload simulation, our design can save on average 27.2% of total power compared to the baseline, and decrease 42.8% average latency compared to the baseline with power-gating.

KEYWORDS:

• Network-on-chip
• low-power
• low-cost
• power-gating
• starvation avoidance

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This paper was supported in part by the National High-Tech 863 Project of China under [grant number 2009AAOIZ102], in part by the National Natural Science Foundation of China under [grant numbers 60873016 and 61170083], and in part by the Doctor Program Foundation of Education Ministry of China [numbers 20114307110001 and 20114307130003].