Improved Server Architecture for Highly Efficient Message Mediation

Enterprise Service Bus facilitates message-based communication between modular software components in a SOA application. In addition to message routing, the ESB communication abstraction includes filtering and transformation capabilities that enable composing separate software modules quickly, with minimal code changes. For this reason, this richer communication capability is often termed "mediation". Mediation is an important tool used in systems built by aggregating many components together, and it is considered to be a key element of SOA. Typically, each message mediated by an ESB undergoes several parse and copy operations thereby incurring a severe performance penalty. This paper presents several optimizations to ESB design that enable lower-overhead message mediation by reducing processing requirements, eliminating buffer copies, and facilitating network-level data transfers. We also detail the performance gains that we have been able to achieve -- close to two orders of magnitude in some cases -- in a redesign of a popular implementation.