Asynchronous Consensus Quorum Read: Pioneering Read Optimization for Asynchronous Consensus Protocols

Abstract

In the era of cloud computing, the reliability and efficiency of distributed systems, particularly in cloud-based databases and applications, are important. State Machine Replication (SMR), underpinning these distributed architectures, commonly utilizes consensus protocols to ensure linearizable operations. These protocols are critical in cloud environments as they maintain data consistency across geographically dispersed data centers. However, the inherent latency in cloud infrastructures poses a challenge to the performance of consensus-based systems, especially for read operations that do not alter the system state and are frequently executed. This paper addresses this challenge by proposing “Asynchronous Consensus Quorum Read” (ACQR), a novel read optimization method specifically designed for asynchronous consensus protocols in cloud computing scenarios. We have incorporated ACQR into Rabia, an advanced asynchronous consensus protocol, to show its effectiveness. The experimental results are encouraging, they demonstrate that ACQR improves Rabia’s performance, achieving up to a 1.7× increase in throughput and a 40% reduction in optimal latency. This advancement represents a critical step in enhancing the efficiency of read operations in asynchronous consensus protocols within cloud computing environments.