Issue No. 05 - May (1972 vol. 21)
E.G. Mallach , Emulation Department, Honeywell Information Systems Inc.
An aerospace guidance computer organization, consisting of multiple processors and memory units attached to a central time-multiplexed data bus, is described. A job mix for this type of computer is obtained by analysis of Apollo mission programs. Multiprocessor performance is then analyzed using: 1) queuing theory, under certain "limiting case" assumptions; 2) Markov process methods; and 3) system simulation. Results of the analyses indicate: 1) Markov process analysis is a useful and efficient predictor of simulation results; 2) efficient job execution is not seriously impaired even when the system is so overloaded that new jobs are inordinately delayed in starting; 3) job scheduling is significant in determining system performance; and 4) a system having many slow processors may or may not perform better than a system of equal power having few fast processors, but will not perform significantly worse.
Aerospace applications, computer system simulation, guidance computers, Markov processes, multiprocessors, queuing theory.
E. Mallach, "Job-Mix Modeling and System Analysis of an Aerospace Multiprocessor," in IEEE Transactions on Computers, vol. 21, no. , pp. 446-454, 1972.