An operating system carries out process management.
Explain one reason why an operating system needs to manage processes.
Mark scheme
Award up to two marks for a linked explanation such as:
- The CPU can only execute one process at a time (1) so the operating system must decide which process runs next (1)
- Each process needs CPU time (1) so the operating system must share the CPU between processes (1)
- One process could use the CPU for too long (1) so the operating system must give other processes a turn (1)
- A process may be waiting for a resource or user input (1) so the operating system can run another process that is ready (1)
- The user wants to run more than one program (1) so the operating system must manage which process uses the CPU and when (1)
For both marks, the expansion must follow/associate with the statement.
Allow 'program' for 'process'.
Do not accept 'to manage processes' / 'so processes are managed' without a reason.
Do not accept answers about managing files, memory or peripherals.
Example answers and how they were marked
The CPU can only run one process at a time, so the operating system must decide which process gets the CPU and for how long.
Why: Linked point (1) and reason (1).
The operating system decides which process runs next.
Why: A correct point (1) but no linked reason.
So that files can be saved in the right place.
Why: This is file management, not process management, so no creditworthy point.