Q. What is Multiprogramming?

Multiprogramming

• When two or more programs are in memory at the same instance, sharing the processor is referred to multiprogramming operating system. Multiprogramming presumes a single processor which is being shared. It increases CPU utilization by organizing jobs so that CPU always has one to execute.

• Fig. below displays the memory layout for a multiprogramming system.

• Operating system keeps many jobs in memory at a time. This set of jobs is a subset of the jobs kept in job pool. Operating system picks and begins to execute one of the job in memory.

• Multiprogrammed system provide an environment in that various system resources are utilized effectively though they don't provide for user interaction with the computer system.

• Jobs entering into the system are kept in the memory. Operating system picks the job and begins to execute one of the job in memory. Having many programs in memory at the same time needs some form of memory management.

• Multiprogramming operating system monitors the state of all active programs and system resources. This makes sure that CPU is never idle unless there aren't any jobs.