A Guide to Parallel Computation and Some Cray-1 Experiences

Publisher Summary This chapter discusses parallel computation and some Cray-1 experiences. A slowdown in the rate of growth of computing power available from a single processor and a dramatic decrease in the hardware cost of executing an arithmetic operation have stimulated users and developers of large-scale computers to investigate the feasibility of parallel computation. The chapter discusses the principles of parallel processing and the experiences with the Cray-1 vector computer. It provides an account of taxonomy of parallel computers that contains existing parallel computers, as well as some under development. The chapter describes hardware modeling. Concerning complexity, a distinction is required between the algorithms suited for sequential processing and those suited for parallel processing. In sequential processing, the time required to process an algorithm is correlated with its complexity, whereas for parallel processing, the time required is to be determined by the number of parallel steps, that is, parallel complexity needed to implement a given algorithm. The chapter focuses on the problems that cannot be coded optimally in FORTRAN.