ADA/UNIX COMPATIBILITY FOR REAL-TIME APPLICATIONS

ACHIEVING HIGH PERFORMANCE AND MEETING REAL-TIME REQUIREMENTS ARE AREAS OF MAJOR CONCERN IN IMPLEMENTING REAL-TIME SYSTEMS IN ADA ON TARGETS RUNNING UNIX OPERATING SYSTEM. STANDARD UNIX LACKS REAL-TIME FEATURES THAT CAN ENABLE AN ADA RUNTIME SYSTEM TO BE DESIGNED SO AS TO ACHIEVE HIGH PERFORMANCE SIMILAR TO THAT OF BARE TARGET ADA IMPLEMENTATIONS. USE OF REAL-TIME UNIX FEATURES SUCH AS PREEMPTIVE SCHEDULING, ASYNCHRONOUS I/O, REAL-TIME TIMERS, MINIMUM AND BOUNDED INTERRUPT LATENCIES, ETC.) WILL IMPROVE THE PERFORMANCE AS WELL AS SIMPLIFY IMPLEMENTATION OF MANY AREAS OF AN ADA RUNTIME SYSTEM. THESE AREAS INCLUDE SCHEDULING, TASKING, INTERRUPTS, MEMORY MANAGEMENT, CHAPTER 13, AND I/O. THIS PROPOSAL ADDRESSES THE METHODS AND TECHNIQUES TO BE USED DURING PHASE I TO IMPLEMENT THE DESIGN OF AN ADA RUNTIME SYSTEM UTILIZING REAL-TIME UNIX/POSIX EXTENSIONS. AN EXISTING ADA RUNTIME SYSTEM IMPLEMENTATION ALONG WITH AN EXISTING REAL-TIME UNIX IMPLEMENTATION WILL BE USED TO DETERMINE THE FEASIBILITY OF THE PROPOSED TECHNIQUES.