Cache Memory: The Ultimate Guide for Operating Systems Students

Question 1

What primary factor influences the size of a cache?

Accepted Answer

Application requirements

Answer

Processor speed

Answer

Memory bandwidth

Answer

Main memory capacity

Question 2

What is the process called when a cache line is replaced with a new block of data from main memory?

Accepted Answer

Cache eviction

Answer

Cache coherence

Answer

Cache locking

Answer

Cache flushing

Question 3

What is the primary purpose of a write-back cache?

Accepted Answer

To minimize writes to main memory

Answer

To improve cache hit rate

Answer

To prevent data inconsistency

Answer

To increase cache capacity

Question 4

Which technique is commonly employed to reduce cache pollution?

Accepted Answer

Victim cache

Answer

Prefetching

Answer

Cache coherency

Answer

Non-uniform cache architecture

Question 5

What is the name of the cache located directly on the processor chip?

Accepted Answer

Level 1 cache

Answer

Level 2 cache

Answer

Level 3 cache

Answer

External cache

Question 6

Which of the following is NOT an advantage of a multi-level cache?

Accepted Answer

Reduced cost

Answer

Reduced cache misses

Answer

Improved performance

Answer

Lower power consumption

Question 7

What is the primary function of a Trace Cache in a processor?

Accepted Answer

Storing recently executed instructions

Answer

Reducing branch mispredictions

Answer

Improving cache hit rate

Answer

Enhancing data locality

Question 8

What is the primary purpose of a cache memory?

Accepted Answer

To provide rapid access to frequently used data and instructions

Answer

To store data that is not currently being processed

Answer

To enhance the overall capacity of the system memory

Answer

To eliminate the necessity for external storage devices

Question 9

Which cache organization method maps each cache line to a specific memory address?

Accepted Answer

Direct mapped

Answer

Set associative

Answer

Fully associative

Answer

None of the aforementioned

Question 10

Which cache replacement algorithm prioritizes the removal of cache lines that have been unused for the greatest amount of time?

Accepted Answer

Least Recently Used (LRU)

Answer

Most Recently Used (MRU)

Answer

First In First Out (FIFO)

Answer

Least Frequently Used (LFU)

Question 11

How does cache size typically affect system performance?

Accepted Answer

Larger caches generally result in improved performance

Answer

Smaller caches are consistently more efficient

Answer

Cache size has no substantial impact on performance

Answer

Larger caches can occasionally diminish performance due to increased latency

Question 12

True or False: In a write-through cache policy, both the cache and main memory are updated during every write operation.

Accepted Answer

True

Answer

False

Question 13

In a multi-level cache hierarchy, which level of cache is typically the largest and slowest?

Accepted Answer

Level 3 (L3) cache

Answer

Level 1 (L1) cache

Answer

Level 2 (L2) cache

Answer

External memory

Question 14

How does prefetching improve cache performance?

Accepted Answer

Prefetches data into the cache before it is requested by the processor, reducing latency and improving performance.

Answer

Replaces less frequently used data in the cache with more frequently used data.

Answer

Physically increases the size of the cache memory.

Question 15

In multiprocessor systems, cache coherency ensures consistency of data across multiple caches. Describe two distinct mechanisms utilized to maintain this coherency.

Accepted Answer

Snooping and Invalidation

Answer

Write-Through and Write-Back

Answer

First-In First-Out and Least Recently Used

Question 16

Which of the following is a benefit of cache memory?

Accepted Answer

Reduced access time

Answer

Improved battery life

Answer

Enhanced graphics processing

Answer

Increased storage capacity

Question 17

What is the role of a cache tag in cache memory?

Accepted Answer

To identify the corresponding main memory address

Answer

To store temporary data

Answer

To indicate whether the cache line is valid

Answer

To track cache usage statistics

Question 18

How does increasing the cache size generally affect the cache miss rate?

Accepted Answer

Reduces it

Answer

Has no effect

Answer

Increases it

Answer

Increases it initially, then decreases

Question 19

Which level of cache memory is typically the closest to the CPU?

Accepted Answer

Level 1 (L1)

Answer

External cache

Answer

Level 3 (L3)

Answer

Level 2 (L2)

Question 20

What is the purpose of a write-through cache?

Accepted Answer

To update main memory immediately upon data write

Answer

To improve data reliability

Answer

To store frequently written data separately

Answer

To reduce CPU overhead

Question 21

Which factors are crucial for optimizing cache performance?

Accepted Answer

Cache hit rate and latency

Answer

Power consumption

Answer

Network bandwidth

Answer

Storage capacity

Question 22

What is an advantage of using a set-associative cache compared to a direct-mapped cache?

Accepted Answer

Higher hit rate due to reduced conflict misses

Answer

Reduced cache miss penalty

Answer

Increased cache size

Answer

Lower power consumption

Question 23

Which metric is commonly used to evaluate cache efficiency?

Accepted Answer

Hit ratio

Answer

Latency

Answer

Bandwidth

Question 24

What is the key difference between a write-back and a write-through cache?

Accepted Answer

Timing of data updates to main memory

Answer

Size of the cache

Answer

Location of the cache

Answer

Purpose of the cache