Programming issues raised by a multiprocessor

As the cost of hardware decreases, it becomes attractive to interconnect multiple processors to form a powerful, cost-effective computer. The end product provided to users, however, is a combination of hardware and software. Because the cost of software development and maintenance dominates the cost of a deliverable system, cheaper hardware, which results in more expensive software, is not cost-effective. For an architecture to be cost-effective, programmers must be able to progrmn it conveniently and efficiently. The question, "Is it programmable?" must be asked for any proposed architecture. In this article we discuss the issues of building software for a multiprocessor, and in the light of these issues consider Cm^*, its operating system (StarOS), and a specific application.