Exploration of Slot Allocation for On-Chip TDM Virtual Circuits

Time-Division-Multiplexing (TDM) Virtual Circuit (VC) has been proposed to guarantee the Quality-of-Service requirements in communication for Network-on-Chip. In this paper, we explore the design space of slot allocation for configuring TDM VCs. Specifically, we investigate different slot assignment schemes, namely, distributed, random and consecutive schemes, which have significant impact on the configurability. We also propose to construct disjoint connected VC sets to effectively reduce the search space. We have realized and integrated them into our VC configuration flow. Our experimental results suggest that the optimal slot allocation cycle equals to the ratio of the link bandwidth to the maximal VC bandwidth, and the distributed slot assignment scheme performs better than the random and consecutive schemes.