Bidirectional Chain Replication for Higher Throughput Provision

Abstract

Provision of higher throughput without sacrificing consistency guarantees in replication systems is a critical problem. In this paper, we propose a novel approach called Bidirectional Chain Replication (BCR) to improve throughput in traditional Chain Replication (CR) through better utilization of computing and communication resources of the chain. Unlike CR where the whole replicated data store is treated as a single unit, in BCR the replicated shared data at each server in the chain is split into two disjoint Logical Partitions (LP 1 , LP 2). This forms two chains running concurrently on the same hardware in two opposite directions; the first chain (CR 1) exclusively manipulates data objects in LP 1 , while the second chain (CR 2) exclusively manipulates data objects in LP 2 , therefore, conflict is avoided and concurrency is guaranteed. The simultaneous employment of these two chains results in better utilization of hardware in the sense that the two chains can evenly share the workload, hence, throughput can be improved without sacrificing consistency. Experimental results showed an improvement of approximately 85% in throughput of BCR over CR.