Packet Triggered Prediction Based Task Migration for Network-on-Chip

Developing IC technology makes Network-on-Chip (NoC) an attractive architecture for future systems. Task migration is important for the overall performance of NoCs since the changing system state makes static task mapping improper for NoCs. The predictability of behaviors of applications makes it possible to use prediction to guide task migration. The trigger to initiate task migration is also an important parameter. In this paper, we first defined and analyzed predictabilities of applications using experimental results. We also compared different triggers for migration and concluded that trigger based on packets sent by single node is the best choice. We modified Genetic Algorithm (GA) mapping for migration and proposed 2 algorithms Simple Exchange (SE) and Benefit Assess (BA). A Node Lock mechanism is also used to reduce the number of migrations. These algorithms and node lock are evaluated using real applications. According to the experimental results, SE reduced 78.7% of migrations with 9% less reduction of latency compared to GA; BA reduced 27.2% of latency, It reduced 72.0% of migrations with almost the same performance compared to GA. The node lock mechanism removed 37.3% and 46.0% of migrations in SE and BA with almost the same performance.