ON THE SUITABILITY OF ADA MULTITASKING FOR EXPRESSING PARALLEL ALGORITHMS

This paper examines the suitability of the Ada multitasking model, for supporting parallel algorithms . The algorithms we consider include both SIMD (single instruction multiple data) and MIMD (multiple in struction multiple data) algorithms ([7]) . These algorithms are typically used in numerical and other computation- intensive programs, where the ability to take advantage of parallelism available in the supporting hardware, is critical for a program's performance. The multitasking facilities of Ada are shown to lack an assential property necessary to support psrallel algorithms : the sbillty to express parallel evaluation and distribution of parameters to the respective tasks . The resulting serial bott leneck could in certa in situations offset the gain from parallelization. Constructs which support parallele valuation and distribution of parameters to parallel tasks are proposed.