Question

Choose the TRUE statement(s) from the following. There can be multiple answers.

1. Paging enables developers to store non-contiguous virtual memory using contiguous physical memory pages.
2. Paging helps eliminate internal fragmentation but suffers from external fragmentation.
3. Page Fault occurs when the valid bit=0 for any given Virtual Page Number (VPN) in the Page Table.
4. Write-through strategy helps improve performance than compared to the Write-back strategy when updating data between main memory and disk.

Answer 1

True statements are that paging maps non-contiguous virtual memory to contiguous physical memory and that a page fault occurs when the valid bit is 0. False statements are that paging eliminates external fragmentation entirely and that write-through is more performant than write-back.

Step-by-step explanation:

The student asked to choose the TRUE statement(s) from the given options:

1. Paging enables developers to store non-contiguous virtual memory using contiguous physical memory pages.
2. Paging helps eliminate internal fragmentation but suffers from external fragmentation.
3. Page Fault occurs when the valid bit=0 for any given Virtual Page Number (VPN) in the Page Table.
4. Write-through strategy helps improve performance compared to the Write-back strategy when updating data between main memory and disk.

The correct answers are:

• Statement 1 is TRUE: Paging allows non-contiguous virtual memory to be mapped to contiguous physical memory pages.
• Statement 3 is TRUE: A Page Fault is indeed an event that occurs when the valid bit in the page table entry is 0, indicating that the page is not currently in physical memory.

However, statements 2 and 4 are FALSE. Paging reduces external fragmentation but may still suffer from internal fragmentation. Moreover, the Write-through strategy is generally less performant than Write-back because it writes directly to main memory each time, which is slower than writing to a cache.