The cost of recovery in message logging protocols

Past research in message logging has focused on studying the relative overhead imposed by pessimistic, optimistic, and causal protocols during failure-free executions. We give the first experimental evaluation of the performance of these protocols during recovery. We discover that, if a single failure is to be tolerated, pessimistic and causal protocols perform best, because they avoid rollbacks of correct processes. For multiple failures, however, the dominant factor in determining performance becomes where the recovery information is logged (i.e. at the sender, at the receiver, or replicated at a subset of the processes in the system) rather than when this information is logged (i.e. if logging is synchronous or asynchronous).