IBM OS/VS1
Thomas F. Wheeler · 1973
A brief study of IBM OS/VS1 (Operating System/Virtual Storage 1) will reveal a system providing many faceted growth capabilities at all levels of user-system interaction. Additional meaningful function is provided on a stabilized base to assure this growth capability. It can be further seen that installation growth is achieved through new application work and not by a continual rework of existing programs. To assure the users ability to move to new work almost immediately, OS/VS1 is built on an IBM OS/MFT (Operating System/Multiprogramming with a Fixed Number of Tasks) base. Compatibility is defined to extend to most object programs, source programs, data and libraries from OS/MFT to OS/VS1, thus assuring a normal movement of existing programs to the virtual environment. Figure 1 graphically represents the areas of change between MFT and VS1.