Performance Measures of the ADA Rendezvous

The Ada Programming Language ADA, was designed to meet the need for a standard computer programming language. Ada has the ability to take advantage of multiprocessor environments. One feature, known as the rendezvous, allows tasks to synchronize in such a environment. In this paper, we will look at the performance of the Ada rendezvous in a two-processor system. In a distributed Ada system, the rendezvous provides synchronized communication between asynchronous tasks. A system of this sort would consist of at least two processors, each serving various tasks. Presently, the performance behavior of tasks which synchronize and possibly communicate are not widely known. Developers of concurrent Ada systems will need to perform sensitivity studies of the Ada tasking environment to develop efficient time-critical programs. Therefore, we will discuss Rendezvous Response Time from the point of view of a sensitivity study. We will show generalized performance curves of the rendezvous along with commentary on their performance elbows or bottlenecks. Rendezvous Response Time will be defined as the amount of time one task must wait until its rendezvous request to another task is completed. The discussion will be based on two separate computer simulations of a two-processor system. The tools to be used to build these simulations are ELSIR and APOSL.