Introduction

Abstract

Supercomputers of any given period are, by definition, the fastest computers available in that period. There is a heavy and steadily increasing demand for supercomputers in a wide range of applications that involve huge amounts of data and require enormous computing power. These application areas include meteorology, defense, nuclear energy, petroleum, aerospace, and general scientific research. The parallel processing era started with the realization that sequential computers were reaching their limit because of restrictions imposed by the laws of physics; all supercomputers today use parallel processing in some form. Parallel processing consists in the exploitation of parallelism at one or more levels (i.e., at job, program, subroutine, loop, statement, or instruction level), and its use is not limited to supercomputers alone.