Dynamic content web applications: Crash, failover, and recovery analysis

This work assesses how crashes and recoveries affect the performance of a replicated dynamic content web application. RobustStore is the result of retrofitting TPC-W's on-line bookstore with Treplica, a middleware for building dependable applications. Implementations of Paxos and Fast Paxos are at the core of Treplica's efficient and programmer-friendly support for replication and recovery. The TPC-W benchmark, augmented with faultloads and dependability measures, is used to evaluate the behaviour of RobustStore. Experiments apply faultloads that cause sequential and concurrent replica crashes. RobustStore's performance drops by less than 13% during the recovery from two simultaneous replica crashes. When subject to an identical faultload and a shopping workload, a five-replicas RobustStore maintains an accuracy of 99.999%. Our results display not only good performance, total autonomy and uninterrupted availability, they also show that it is simple to develop efficient recovery-oriented applications using Treplica.