Load distribution with the proximity congestion awareness in a network on chip

This work proposes a proximity congestion awareness (PCA) technique, where switches use the load information of neighbouring switches, called stress values, for their own switching decisions, thus avoiding congested areas and the maximum tolerable load of the network.

Abstract

In networks on chip (NoC) very low cost and high performance switches are of critical importance. For a regular two-dimensional NoC, we propose a very simple, memoryless switch. In the case of congestion, packets are emitted in a non-ideal direction, also called deflective routing. To increase the maximum tolerable load of the network, we propose a proximity congestion awareness (PCA) technique, where switches use the load information of neighbouring switches, called stress values, for their own switching decisions, thus avoiding congested areas. We present simulation results with random traffic which show that the PCA technique can increase the maximum traffic load by a factor of over 20.