RAPA: reliability-aware priority arbitration strategy for network on chip

Reliability issue, especially from transient errors due to scaling IC technology, low voltage supply, high frequency and heavy thermal effects, particles emission etc, has become a challenge for NoC design. Focus on this problem, an effective Reliability-Aware Arbitration Strategy simplified as RAPA, is proposed in this paper to decide which flits should be prioritized in the network transmission for higher application-level reliability. Different from pervious performance-oriented arbitration strategies, it includes the application-level reliability requirement to determine the reliability priority ranking. Flits patching mechanism is also used for avoiding starvation. The evaluation metric is redefined to emphasizing application-level reliability. Finally, we verify the reliability based prioritization policy on cycle accurate platform. And the simulation results show that the averaged successful delivery rate is upgraded from three nine of round robin (RR), old age based arbitration(OA) to five nine of our method RAPA. Especially, 67.15%, 41.83% reliability improvement in rest unreliable space on average are obtained over typical RR policy and OA based arbitration policy respectively with guaranteed performance.