Fast Raft Replication for Transactional Database Systems over Unreliable Networks

Raft, a consensus algorithm, has been widely used in many open source database systems to enhance the availability and to guarantee the consistency. However, due to the constraint of coherent log entries, the transactional database systems adopting Raft replication do not perform well in the case of unreliable network environment. This is because with the relatively frequent occurrence of network failures, the serial log replication—which is guaranteed by the log coherency—can block the commit of transactions. In this paper, we propose the fast Raft replication (FRaft) protocol. FRaft adopts the term coherency property, which has a good tolerance for the unstable networks. Meanwhile, FRaft can be implemented easily by extending the basic Raft. Our experimental results show that our replication scheme has better throughput.