Flease - Lease Coordination Without a Lock Server.

Large-scale distributed systems often require scalable and fault-tolerant mechanisms to coordinate exclusive access to shared resources such as files, replicas or the primary role. The best known algorithms to implement distributed mutual exclusion with leases, such as Multipaxos, are complex, difficult to implement, and rely on stable storage to persist lease information. In this paper we present {\bf F}LEASE, an algorithm for fault-tolerant lease coordination in distributed systems that is simpler than Multipaxos and does not rely on stable storage. The evaluation shows that {\bf F}LEASE can be used to implement scalable, decentralized lease coordination that outperforms a central lock service implementation by an order of magnitude.