Predicting multiprocessing efficiency on the Cray multiprocessors in a (CTSS) time-sharing environment/application to a 3-D magnetohydrodynamics code

1 July 1988

journal article
Published by AIP Publishing in Computers in Physics

Vol. 2 (4) , 62-67
https://doi.org/10.1063/1.168304

Abstract

A formula is derived for predicting multiprocessing efficiency on Cray supercomputers equipped with the Cray Time-Sharing System (CTSS). The model is applicable to an intensive time-sharing environment. The actual efficiency estimate depends on three factors: the code size, task length, and job mix. The implementation of multitasking in a three-dimensional plasma magnetohydrodynamics (MHD) code, TEMCO, is discussed. TEMCO solves the primitive one-fluid compressible MHD equations and includes resistive and Hall effects in Ohm’s law. Virtually all segments of the main time-integration loop are multitasked. The multiprocessing efficiency model is applied to TEMCO. Excellent agreement is obtained between the actual multiprocessing efficiency and the theoretical prediction.

Keywords

This publication has 0 references indexed in Scilit: