High Quality Content by WIKIPEDIA articles! In the history of IBM mainframe operating systems, multiprogramming with a fixed number of tasks (MFT) was one of the three available configurations of the OS/360's control program. In turn, OS/360 was an operating system for the IBM System/360 line of computers. MFT was intended to serve as a stop-gap until Multiprogramming with a Variable number of Tasks (MVT), the intended "target" configuration of OS/360, became available in 1967. Early versions of MVT had many problems, so simpler MFT continued to be used for many years. After introducing new System/370 machines with virtual memory, the MFT was developed in 1972 into OS/VS1, the last system of this particular line.