Resource management for raft consensus protocol

Abstract

Protocols which solve agreement problems are essential building blocks for fault-tolerant distributed applications. Especially, many consensus protocols have been proposed in recent decades. Paxos is the most famous consensus protocol, but it is difficult to understand and even more to implement. The recently proposed raft consensus protocol is a leader based consensus protocol. It is a simple enough to understand itself. Given the popularity of cloud-based elastic environments, it should consider adapting such environments. This paper proposes a resource management mechanism for raft protocol. It realises a dynamic raft cluster by introducing the flexible resource management and the notion of suspended nodes. In this mechanism, a leader node arouses suspended nodes when some nodes failed, or nodes come up against a heavy load. It can realise an appropriate configuration on the number of nodes in a service. As a result, it can reduce energy consumption during execution. Then, we show the performance evaluation of the proposed protocol regarding the number of messages sent by nodes and the number of execution steps for consensus executions. We also show the message-efficiency and the cost for the resource management mechanism by comparing the proposed protocol with raft protocol.