Porting and Enhancements of a Real-time Object-Oriented Operating System

This paper describes our experiences in porting a distributed object oriented real-time operating system called Apertos1 to a new RISC platform, and some enhancements made to improve its performance. Apertos employs an objectmetaobject hierarchy to facilitate object heterogeneity. This meta-hierarchy is intended to support various objects with different requirements such as real-time constraints. As such a system grows, satisfying differing object requirements via the meta-hierarchy with its related communication overheads is orthogonal to achieving real-time response performance. To address this, we introduce preemptive scheduling and a hierarchical scheduling solution.