Research On Adaptive Network-on-Chip Routing Algorithm Based On Torus Topology

With the development of semiconductor technology and the improvement of chip integration,the on-chip communication based on traditional bus architecture is unable to meet the requirement of communication between modules.Network on chip introduces the network communication to the on-chip communication architecture,using the packet-switch for communication,which dramatically improves the communication bandwidth and network scalability.Because of its superior performance,the topology,routing algorithm,exchange mechanism of network on chip has attracted many research institutions and universities.The routing algorithm as a key protocol of packet forwarding in network on chip has a very important influence on the overall performance of the network.Therefore,how to design an efficient and low power routing algorithm has become the focus of research.In this paper,the key technologies of the network on chip are analyzed,including topology structure,routing algorithm,routing structure and switching mode.The influence of different topology strategies and virtual channels on the performance of network on chip are simulated by open source simulation platform.According to the experimental results,the Torus topology is chosen as the topology of the routing algorithm,and the appropriate virtual channel number partitioning range is determined.According to the structural characteristics of Torus topology network,this paper presents a TD routing algorithm for 2D Torus topology and RTTD routing algorithm for 3D Torus topology.The two routing algorithms use the distance between the next hop alternate routing nodes and destination node to make the routing decision.When the distance between the next hop alternate routing node and the target node in the network are equal,the partially adaptive routing is used for the congestion of the next hot routing node.TD and RTTD use 6 virtual channels to avoid deadlock.The RTTD routing algorithm introduces the probability quadrant distribution according to the position relationship between source node and destination node.According to the structural characteristics of the 3D Torus network,the RTTD routing algorithm can achieve the goal of balancing the network load by randomly selecting the routing direction of the packet.In order to verify the validity of the routing algorithm,this paper simulates the routing algorithm on the Nirgam open source simulation platform and improves the platform structure to support the 3D Torus topology.The average delay and network power consumption in different network scale,uniform and hotspot flow mode are evaluated,and compared with XY,OE,XYZ and Dy XYZ routing algorithms.The experimental results show that TD and RTTD routing algorithm has better performance in hotspot traffic mode.The network packet delay time reduces more than 4%,while the average energy consumption reduces more than 8% in TD routing algorithm compared with the XY and OE routing algorithm.The network packet delay time reduces more than 2.4%,while the average energy consumption reduces more than 2.5% in RTTD routing algorithm compared with XYZ and Dy XYZ routing algorithm.This paper completes the design and implementation of adaptive routing algorithm based on 2D Torus topology and 3D Torus topology,which effectively improves the performance of network in hotspot traffic mode and reduces the power consumption of network communication.This paper provides some reference for further research and exploration of No C routing algorithm.