Regulating Degree of Adaptiveness for Performance-Centric NoC Routing

In the network-on-chip (NoC) communication framework, congestion in priority-fixed shortest routes may result in poor network performances in terms of increasing packet latency, and reduced throughput value. Here, the employment of adaptive routing allows more freedom in selecting an alternate congestion-free route in minimal or non-minimal direction. Though the selection of an output link in non-minimal directions based on local congestion information may also degrade network performance rather than improving due to the increasing number of resource sharer in a longer route. Moreover, packet routing using a longer route may not support guaranteed throughput (GT) intensive real-time applications. In addition, allowing freedom in the non-minimal route increases the chance of occurring deadlock and live-lock cycles. In this work, we follow an adaptive routing approach that relies on reserving a virtual path for routing packet in both minimal and non-minimal direction while satisfying the application demands in meeting the hard deadline of packet arrival time and guaranteed minimum throughput. In the proposed work, we also investigate to figure out a trade-off between given routing flexibility and overall network performances under the presence of various data traffics. Our experimental results reveal that fixing this range in non-minimal direction at run time is more beneficial than always selecting a specific value, as the deflection range varies based on underlying application demands and present network traffic situation.