ABSTRACT

Although Ada is now ten years old, there are still not firm guidelines as to how the distribution of an Ada program onto multiprocessors should be organised, specified and implemented. There is considerable effort being expended on identifying and solving problems associated with distributed Ada, and the first aim of this paper is to set out where the work is being done, and how far it has progressed to date. In addition to work of a general nature, there are now nearly ten completed distributed Ada implementations, and a second aim of the paper is to compare these briefly, using a method developed as part of the Stadium project at the University of Southampton. Much of Southampton's motivation for getting involved in distributed Ada has been the interest from the strong concurrent computing group, which has for several years taken a lead in parallel applications on transputers. The paper concludes with a classification of parallel programs and a description of how the trends in distributed Ada will affect users in the different groups.

COLLECTIVE WORK ON DISTRIBUTED ADA

The major forums where work on distributed Ada is progressing are Ada UK's International Real-Time Issues Workshop, the Ada 9X Project, SIGAda ARTEWG and AdaJUG CARTWG. Reports of these meetings appear regularly in Ada User (published quarterly by Ada UK) and Ada Letters (published bi-monthly by ACM SIGAda). The status of their activities is summarised here.