Consistent hashing with bounded loads and virtual nodes-based load balancing strategy for proxy cache cluster

Abstract

Response time and bandwidth occupancy of backbone network are greatly affected by load balancing and cache hit ratio in proxy cache cluster (PCC). A novel load balancing strategy is proposed to improve the homogeneous and heterogeneous PCC performance. By combining with the different performance parameters, performance ratio can be formulated with independent information data fluctuation weighting method, and the virtual nodes (VNs) attached to every cache node (CN) can be generated by a random function. The greatest common divisor m of the number of VNs attached to every CN can be calculated and the hash ring is cut into m arcs, and the VNs are mapped proportionally to arcs of the hash ring by the MD5 function. Requests are assigned to VNs based on the forwarding rule of consistent hashing with bounded loads, and the CN in correspondence with the VNs will be selected to provide services. Simulation results show that the strategy can significantly improve the load balancing in homogeneous and heterogeneous PCC, effectively reduce bandwidth occupancy of backbone network and PCC response time.