When a program closes, the operating system frees the main memory it was using.
Explain one reason why the operating system frees main memory when a program closes.
Mark scheme
Award up to two marks for a linked explanation such as:
- The memory can be reused/allocated to another program (1) so other programs have enough main memory to run (1)
- Freeing the memory stops main memory becoming full (1) so the computer can load/run new programs (1)
- The closed program's data is no longer needed (1) so keeping it would waste main memory (1)
- The operating system can give the freed memory to a program that needs more (1) so that program can continue to run (1)
For both marks, the expansion must follow/associate with the statement.
Do not accept 'to make the computer faster' on its own without saying how freeing memory helps.
Do not accept 'to delete the program' or 'to save the program' because closing a program does not remove it from secondary storage.
Example answers and how they were marked
The memory can be reused by another program, so other programs have enough main memory to run.
Why: Linked point (1) about reusing the memory and reason (1) that other programs then have enough memory.
So that the memory is free.
Why: Gives the point (1) but does not give a linked reason saying what the free memory is used for.
So the program is deleted from the computer.
Why: No creditworthy point; closing a program does not delete it from secondary storage.