Question

Replacements policies for different pages is required when.

• A. There is no unused page frames in main memory
• B. Allocation of new incoming item
• C. Both $\left(1\right)$ and $\left(2\right)$
• D. None of these

Answer 1

The correct option is C Both $\left(1\right)$ and $\left(2\right)$

Replacement policies for different pages is required when there is no unused page frames in main memory and allocation of new item. In a computer operating system that uses paging for virtual memory management, page replacement algorithms decide which memory pages to page out, sometimes called swap out, or write to disk, when a page of memory needs to be allocated. A page replacement algorithms looks at the limited information about accesses to the pages provided by hardware, and tries to guess which pages should be replaced to minimize the total number of pages misses.