Some problems in distributing real-time Ada programs across machines

摘要

The Ada Research Group of the Robotics Research Laboratory at The University of Michigan is currently developing a real-time distributed computing capability based upon the premises that real-time distributed languages provide the best approach to real-time distributed computing and, given the focus on the language level, that Ada offers an excellent candidate language. The first phase of the group's work was on analysis of real-time distributed computing. The second, and current, phase is the development of a pretranslator which translates an Ada program into n Ada programs, each being targeted for one of a group of processors and each having required communication support software automatically created and attached by the pre-translator. This paper describes the pretranslator being developed and a number of issues which have arisen with regard to the distributed execution of a single Ada program, including language semantics, objects of distribution and their mutual access, network timing, and execution environments.