Multi-programming OS

Multi-programming OS: 

Multi-programming is the interleave execution of two or more processes be a single CPU computer system. Here, jobs are broadly classified into the following two types:

1. CPU-bound jobs.
2. I/O-bound jobs.

Requirements of multi-programming system:

1. Large memory
2. Memory protection
3. Job status preservation
4. Proper job mix
5. CPU scheduling

Example: UNIX, IBM VM

Figure: Multi-programming OS