Some Types of Parallel Algorithms

Along with the progress of the micro-electronics technology, various types of multi-processor systems have been developed experimentally, and various types of representations of parallel algorithms have been adopted on trial. In this paper, we attempt to classify the types of parallel algorithms from the viewpoint of the composition of actions executable in parallel (we call them parallel actions in short). Three types of them are as follows. 1) the number of parallel actions is known from the source program. 2) some parallel actions are created or deleted depending on the execution of one action. 3) the number of the parallel actions is changeable dynamically depending on some processing in the past. From this classification we can derive some suggestion concerning the programming language suitable to parallel algorithms and the multi-processor system being able to execute these algorithms