Clustering OSGI Applications Using Distributed Shared Memory

Modern applications are no longer monolithic and centralized, they have become distributed, modular and dynamic. The OSGi Service Platform is thus commonly used for building modularized and dynamic Java applications, but its distribution model however relies on communication protocols using remote invocation semantics. Distributed Shared Memories (DSM) pro- vide an unusual approach to ease distribution by transparently sharing the state of targeted objects in an application without changing the initial data access paradigm. This paper describes how DSM principles can be efficiently used in order to simplify the clustering of dynamic services. The proposed approach consists in transparently integrating DSM into the OSGi service model using containers and annotations. It has been implemented using the Apache Felix framework, the iPOJO component model and the Terracotta DSM, and has been validated in three use cases.