COLLECTION ORDERING FOR REPLICATED STATE MACHINES

摘要

A replicated state machine with N replica servers may be configured to tolerate a count of F faults. A first operation (of a first ordering type) executes when a first quorum of correctly functioning replicas is available. A second operation (also of the first operation type) executes when a second quorum of correctly functioning replicas is available. A third operation (of a second ordering type) executes when a third quorum of correctly functioning replicas are available. The operations are executed by the replicated state machine such that: (1) the replicated state machine does not guarantee operational ordering between the first operation and the second operation; (2) the replicated state machine guarantees ordering between the first operation and the third operation; and (3) the replicated state machine guarantees ordering between the second operation and the third operation.