Very High - speed Computing Systems

Very high-speed computers may be clnssified as follows: 1) Single Jktmction Strdingle Data Stream (SISD) 2) S i l e Imbnctioa Stream-Multiple Data Stream (SIMD) 3) Multiple hstmcth StrePntSingle Data Stream (MSD) 4) Mnltiple Instroctioo Stream-Multiple Data Stream (”D). “Stream,” as nsed here, refers to the sequence of data or irstructiom as seen by the machine daring tbe execution of a program. m e coastitaeats of a system :storage, exeation, and htrudon bandhg (braoching) are dkcussd witb regard to recent developmen6 and/or systems Limitatim. The COlsMnents are dkcuwd m term of coocarrent SED Manuscript received June 30,1966; revised August 16,1966. This work was performed under the auspices of the U. S. Atomic Energy Commission. The author is with Northwestern University, Evanston, Ill., and Argonne National Laboratory, Argonne, Ill. systems (CDC 6600 series and, io particnlar, IBM Modd 90 series), since mnltiple stream organizations usually do not quire any more elaborate compooents. Representative organizations are s e l e c t e d from each class and the arrangement of the comtitwnts is shown.