Optimal link scheduling on improving best-effort and guaranteed services performance in network-on-chip systems

With the advent of the multiple IP-core based design using network on chip (NoC), it is possible to run multiple applications concurrently. For applications with hard deadline, guaranteed services (GS) are required to satisfy the deadline requirement. GS typically under-utilizes the network resources. To increase the resources utilization efficiency, GS applications are always complement with the best-effort services (BE). To allow more resource available for BE, the resource reservation for GS applications, which depends heavily on the scheduling of the computation and communication, needs to be optimized. In this paper we propose a new approach based on optimal link scheduling to judiciously schedule the packets on each of the links such that the maximum latency of the GS application is minimized with minimum network resources utilization. To further increase the performance, we propose a router architecture using a shared-buffer implementation scheme. The approach is formulated using integer linear programming (ILP). We applied our algorithm on real applications and experimental results show that significant improvement on the overall execution time and link utilization can be achieved.