Question

In the context of operating systems, which of the following statements is/are correct with respect to paging?

• A. Paging helps solve the issue of external fragmentation.
• B. Page size has no impact on internal fragmentation.
• C. Paging incurs memory overheads.
• D. Multi-level paging is necessary to support pages of different sizes.

Hint:

Paging removes external fragmentation but introduces internal fragmentation and page table overheads.

Answer 1

The Correct Option is A, C

Step 1: External fragmentation.
Paging divides memory into fixed-size frames and processes into pages of the same size. Since any page can be placed into any free frame, paging eliminates external fragmentation. Hence, statement (A) is correct.

Step 2: Internal fragmentation.
Internal fragmentation depends on page size. Larger page sizes may lead to more unused space in the last page of a process. Therefore, page size does affect internal fragmentation, making statement (B) incorrect.

Step 3: Memory overhead.
Paging requires page tables to store address mappings. These page tables occupy memory, resulting in memory overheads. Hence, statement (C) is correct.

Step 4: Multi-level paging.
Multi-level paging is used to reduce page table size, not to support multiple page sizes. Therefore, statement (D) is incorrect.

Final Answer: (A), (C)