Multi-Ring Paxos

This paper addresses the scalability of group communication protocols. Scalability has become an issue of prime importance as data centers become commonplace. By scalability we mean the ability to increase the throughput of a group communication protocol, measured in number of requests ordered per time unit, by adding resources (i.e., nodes). We claim that existing group communication protocols do not scale in this respect and introduce Multi-Ring Paxos, a protocol that orchestrates multiple instances of Ring Paxos in order to scale to a large number of nodes. In addition to presenting Multi-Ring Paxos, we describe a prototype of the system we have implemented and a detailed evaluation of its performance.