Performance consequences of inconsistent client-side membership information in the open group model

In a distributed fault-tolerant server system realized according to the open group model, inconsistency will (temporarily) arise between the dynamic membership of the replicated service and its client-side representation in the event of server failures and recoveries. The paper proposes techniques for maintaining this consistency and discuss their performance implications in failure/recovery scenarios where clients load balance requests on the servers. Comparative performance measurements is carried out for two of the proposed techniques. The results indicate that the performance impact of lacking consistency is easily kept small, and that the cost of the technique is small.