CARM: Congestion Adaptive Routing Method for On Chip Networks

Network-on-Chip (NoC) has emerged as a long-term and efficient on-chip communication solution for MCSoC and CMP micro-architectures to overcome bottleneck of traditional bus-based interconnects. Performance of NoC is highly dependent on routing algorithm we choose. In this paper, we present a highly adaptive and deadlock free routing algorithm for 2D mesh topology to mitigate congestion. Proposed algorithm provides a high degree of adaptive ness by allowing cycles in channel dependency graph and using one additional virtual channel along the Y dimension only. It uses all available minimal/non-minimal paths between source and destination nodes. A packet is routed along the non-minimal path only when minimal paths get congested at the neighboring nodes. Results show that proposed congestion-aware routing algorithm improves network performance by routing packets through non-congested areas.