Database Proxies for Component-Based Real-Time Systems

We introduce the concept of database proxies capable of mitigating the gap between two disjoint productivity-enhancing techniques: Component Based Software Engineering (CBSE) and Real-Time Database Management Systems (RTDBMS). The coexistence of the two techniques is neither obvious nor intuitive since CBSE and RTDBMS promotes opposing design goals, CBSE promotes encapsulation and decoupling of component internals from the component environment, whilst RTDBMS provide mechanisms for efficient and predictable global data sharing. Database proxies decouple components from an underlying database residing in the component framework. This enables components to remain encapsulated and reusable, while providing temporally predictable access to data maintained in a database. We specifically target embedded systems with a subset of functionality with real-time requirements. Our implementation results show that the above benefits do not come at the expense of run-time overheads or less accurate timing predictions.