What is uniprogramming
Uniprogramming means one program sits in main memory at a time. Uniprogramming was used in old computers and mobiles. When the computer starts then operating system and application programs are loaded into main memory. We only count user programs running in RAM. RAM is also called main memory.
In old operating systems (OS) only one program runs on the computer at a time. Either of the browser, calculator or word processor runs at a time. These type of operating systems in which one program runs at a time are known as Uniprogramming operating systems.
What is multiprogramming
In multiprogramming, multiple programs reside in main memory (RAM) at a time. OS which handles multiple programs at a time is known as multiprogramming operating system. One processor or CPU can only run one process at a time. OS use context switching in main memory for running multiple programs. Context switching is to switch programs so all programs are given a suitable amount of time. OS can handle only a limited number of programs. If we run many programs on the computer or mobile then the computer becomes very slow or unresponsive.
Uniprogramming vs multiprogramming
In Uniprogramming only one program sits in main memory so it has a small size. But in the case of multiprogramming main memory needs more space. Uniprogramming system runs smoothly as only one task is run at a time. The slow processor can also work well in Uniprogramming but in multiprogramming processor needs to be fast. In multiprogramming large space of RAM is needed. Fixed size partition is used in Uniprogramming. Both fixed and variable size partition can be used in multiprogramming systems.
Example of uniprogramming
- Batch processing in old computers and mobiles
- The old operating system of computers
- Old mobile operating system
Example of multiprogramming
- Modern operating systems like Windows XP and Windows 7,8,10