Advanced Memory Management MCQs

1. Multi-level paging is used to:

a) Reduce page table size b) Increase page table size c) Reduce TLB misses d) None of the above

Correct Answer: a) Reduce page table size

Explanation:
Multi-level paging divides the page table into smaller pieces, storing only the actively needed portions in memory, significantly reducing memory usage for page tables.

2. In segmentation with paging, each segment is divided into:

a) Pages b) Frames c) Blocks d) None of the above

Correct Answer: a) Pages

Explanation:
This hybrid approach first divides memory into logical segments, then further divides each segment into fixed-size pages to combine the benefits of both techniques.

3. Inverted page tables are used to:

a) Reduce page table size b) Increase page table size c) Improve TLB performance d) None of the above

Correct Answer: a) Reduce page table size

Explanation:
Inverted page tables maintain one entry per physical frame rather than per virtual page, dramatically reducing table size (especially for 64-bit systems).

4. Which of the following is a hybrid approach?

a) Pure segmentation b) Pure paging c) Segmentation with paging d) None of the above

Correct Answer: c) Segmentation with paging

Explanation:
Segmentation with paging combines logical division (segments) with fixed-size allocation (pages) to get benefits of both approaches while minimizing their drawbacks.

5. Overlays are used when:

a) Memory is limited b) CPU speed is slow c) Disk space is limited d) None of the above

Correct Answer: a) Memory is limited

Explanation:
Overlays allow programs larger than physical memory to run by swapping code modules in/out of the same memory region as needed.

6. Overlays are managed by:

a) Operating System b) Compiler c) User d) None of the above

Correct Answer: c) User

Explanation:
Unlike modern virtual memory managed by the OS, overlay structures must be explicitly designed by programmers and implemented by compilers.

7. Which scheme allows dynamic loading of programs?

a) Overlays b) Swapping c) Paging d) None of the above

Correct Answer: a) Overlays

Explanation:
Overlays enable dynamic loading by allowing different program modules to occupy the same memory region at different times during execution.

8. The main disadvantage of overlays is:

a) Increased execution time b) Increased memory usage c) Increased disk I/O d) None of the above

Correct Answer: a) Increased execution time

Explanation:
Overlays slow down program execution due to frequent swapping of modules between memory and disk, though they enable running larger programs in limited memory.

9. Which of the following is not a page replacement algorithm?

a) FIFO b) LRU c) MRU d) None of the above

Correct Answer: c) MRU

Explanation:
While FIFO (First-In-First-Out) and LRU (Least Recently Used) are standard page replacement algorithms, MRU (Most Recently Used) is not typically used as it would replace actively used pages.

10. In demand paging, a page is loaded when:

a) It is first created b) It is referenced c) The system is idle d) None of the above

Correct Answer: b) It is referenced

Explanation:
Demand paging follows the principle of lazy loading - pages are only brought into memory when they're actually accessed (on first reference), not preemptively.

11. The working set model is used to prevent:

a) Deadlock b) Thrashing c) Fragmentation d) None of the above

Correct Answer: b) Thrashing

Explanation:
The working set model tracks the set of pages a process is actively using to ensure adequate memory allocation and prevent thrashing (excessive page faults).

12. The TLB (Translation Lookaside Buffer) is used to:

a) Speed up address translation b) Reduce page faults c) Increase memory size d) None of the above

Correct Answer: a) Speed up address translation

Explanation:
The TLB is a special cache that stores recent page table entries to avoid having to access the full page table in memory for every address translation.

13. Which of the following is a non-contiguous allocation technique?

a) Paging b) Segmentation c) Both a and b d) None of the above

Correct Answer: c) Both a and b

Explanation:
Both paging and segmentation allow a process's memory to be allocated in non-contiguous physical locations, unlike contiguous allocation schemes.

14. The optimal page replacement algorithm is:

a) Used in practice b) Used as a benchmark c) Not possible to implement d) None of the above

Correct Answer: b) Used as a benchmark

Explanation:
The optimal algorithm (OPT) is theoretical since it requires future knowledge of page references, but serves as an ideal standard to compare real algorithms against.

15. In multi-level paging, the page table is:

a) A single-level structure b) A hierarchical structure c) Stored in TLB d) None of the above

Correct Answer: b) A hierarchical structure

Explanation:
Multi-level paging creates a tree-like hierarchy of page tables, where outer page tables point to inner page tables, reducing memory usage by only storing active portions.

16. The main advantage of segmentation is:

a) No internal fragmentation b) Logical division of programs c) Faster execution d) None of the above

Correct Answer: b) Logical division of programs

Explanation:
Segmentation mirrors a program's natural structure (functions, arrays, etc.), making it easier to share code/data and implement protection at logical unit boundaries.

Advanced Memory Management MCQs

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