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.