Alternative Edge-Server Architectures for Enterprise JavaBeans Applications

Edge-server architectures are widely used to improve webapplication performance for non-transactional data. However, their use with transactional data is complicated by the need to maintain a common database that is shared among different edge-servers. In this paper we examine the performance characteristics of alternative edge-server architectures for transactional Enterprise JavaBeans (EJBs) applications. In one architecture, a remote database is shared among a number of edge-servers; in another, edge-servers maintain cached copies of transactionally-consistent EJBs. Importantly, the caching function is transparent to applications that use it. We have built a prototype system in which edge-servers are enhanced with an EJB caching capability. The prototype enables a realistic comparison of these architectural alternatives. We use a benchmark EJB application to drive a performance analysis of the architectures. We also compare these edge-server architectures to a classic clustered datacenter architecture.