Monoprogramming and multiprogramming are two different memory and CPU utilization strategies for running programs in an operating system.
Monoprogramming
In monoprogramming, only one program can run in the main memory at a time. All system resources, including CPU and memory, are dedicated solely to that single program until it finishes execution.
Characteristics:
- Simple: Only one program runs, making memory and process management straightforward.
- Low CPU Utilization: While the program waits (e.g., for I/O operations), the CPU remains idle, leading to inefficient utilization.
- Single Tasking: Only one task can be processed by the CPU at any given time.
Example: Early operating systems (such as DOS) and very simple microcontrollers often use monoprogramming, as they only handle one process or application at a time.
Multiprogramming
In multiprogramming, multiple programs reside in memory simultaneously. The operating system manages the CPU to switch between programs, ensuring efficient use of system resources.
Characteristics:
- Efficient CPU Utilization: When one program is waiting for I/O operations, the CPU can switch to another program, thus maximizing CPU usage.
- Concurrent Execution: Programs appear to run concurrently, though, in reality, the CPU switches rapidly between them.
- Resource Sharing: Memory and CPU are shared among multiple programs, improving throughput and system efficiency.
Example: Modern operating systems like Windows, Linux, and macOS are multiprogramming environments, allowing users to run several applications at the same time.
Comparison Monoprogramming vs Multi- programming
