2015 IEEE 34th International Performance Computing and Communications Conference (IPCCC) (2015)
Dec. 14, 2015 to Dec. 16, 2015
Jehan-Francois Paris , Department of Computer Science, University of Houston, TX, USA 77204-3010
Darrell D. E. Long , Department of Computer Science, University of California, Santa Cruz, USA 95064
Raft is a new distributed consensus algorithm that is easier to understand than the older Paxos algorithm. Raft's major drawback is its high energy footprint: as it relies on static quorums for deciding when it can commit updates, it requires five participants to protect against two simultaneous failures. We propose to reduce this footprint by replacing the static quorums that Raft currently uses by quorums that vary according to the number of currently available participants. We present first a modified dynamic-linear voting protocol that disables single-server updates and show that a Raft cluster with four participants managed by this protocol would be almost as available as a conventional Raft cluster with five participants and always tolerate the irrecoverable failure of any single participant without any data loss. In addition, we show a Raft cluster with three participants and a witness managed by an unmodified dynamic-linear voting protocol would be more available than a conventional Raft cluster with five participants and could still tolerate most irrecoverable failures of any single participant while maintaining recoverability.
Raft algorithm, Distributed computing, Fault-tolerant computing, Green computing, Distributed consensus
J. Paris and D. D. Long, "Pirogue, a lighter dynamic version of the Raft distributed consensus algorithm," 2015 IEEE 34th International Performance Computing and Communications Conference (IPCCC), Nanjing, China, 2015, pp. 1-8.