Memory Management — Practice MCQs for CCAT

Correct Answer: B — External fragmentation

Paging eliminates external fragmentation (may have internal).

Correct Answer: B — Logical divisions of program

Segmentation divides memory based on logical units (code, data, stack).

Correct Answer: C — Optimal (Belady's)

Optimal algorithm replaces page not needed for longest time (theoretical).

Correct Answer: B — Translation Lookaside Buffer

TLB is a cache for page table entries to speed up address translation.

Correct Answer: B — Uses smallest sufficient hole

Best fit finds smallest hole that is big enough.

Correct Answer: B — Uses first sufficient hole

First fit allocates first hole that is large enough.

Correct Answer: B — Fixed partitioning/Paging

Fixed size partitions cause internal fragmentation (unused space within partition).

Correct Answer: B — Virtual page to physical frame

Page table translates virtual page numbers to physical frame numbers.

Correct Answer: B — Only when needed

Demand paging loads pages into memory only when accessed.

Correct Answer: C — FIFO

FIFO can have more page faults with more frames (Belady's anomaly).

Correct Answer: B — Programs larger than physical memory to run

Virtual memory allows execution of programs larger than available physical memory.

Correct Answer: B — Required page is not in memory

Page fault occurs when the required page is not found in main memory.

Correct Answer: B — System spends more time paging than executing

Thrashing occurs when excessive paging reduces CPU utilization dramatically.

Correct Answer: B — Determine optimal page allocation

Working set model determines the set of pages a process actively uses.

Correct Answer: B — Reduce external fragmentation

Compaction combines free memory fragments into one contiguous block.

Correct Answer: B — Virtual address

Logical address (virtual address) is generated by CPU; mapped to physical address.

Correct Answer: A — Memory Management Unit

MMU (Memory Management Unit) translates virtual addresses to physical addresses.

Correct Answer: D — Equal to frame size and fixed

Page size equals frame size and is fixed, typically a power of 2 (e.g., 4KB).

Correct Answer: B — Replaces least recently used page

LRU replaces the page that has not been used for the longest time.

Correct Answer: B — Moving entire process between memory and disk

Swapping moves entire processes between main memory and disk.