Memory Hard 40

Study Flashcards Play Quiz

Questions and Answers

What is the main difference between DRAM and SRAM?

DRAM is slower and requires refreshing, while SRAM is faster and does not require refreshing.

Which type of memory is typically used for permanent or semi-permanent data storage?

ROM

What is the relationship between the speed and cost of memory in the memory hierarchy?

The speed and cost of memory are inversely proportional, with faster memory being more expensive.

Which type of RAM is typically used to build cache memory?

SRAM Signup and view all the answers

What is the primary purpose of virtual memory in a computer system?

To allow the system to run multiple programs concurrently by providing isolated memory spaces. Signup and view all the answers

Which of the following is a key characteristic of the memory hierarchy in a computer system?

The memory hierarchy is organized based on the speed and cost of different memory types. Signup and view all the answers

What is the primary purpose of cache memory in a computer system?

To improve the performance of the memory hierarchy by caching frequently accessed data. Signup and view all the answers

Which of the following is a key difference between DRAM and SRAM?

DRAM requires refreshing to maintain data, while SRAM does not require refreshing. Signup and view all the answers

What is the purpose of the tag, block, and offset fields in the mapping of main memory to cache?

To specify the location of the data in the cache Signup and view all the answers

What is the key difference between direct mapped cache and fully associative cache?

Direct mapped cache has a fixed mapping between main memory and cache blocks, while fully associative cache allows a block to be placed anywhere in the cache. Signup and view all the answers

What is the purpose of the offset field in the memory address format?

To specify the location of the data within a cache block Signup and view all the answers

How does the number of bits in the main memory address affect the cache design?

All of the above Signup and view all the answers

What is the key advantage of a fully associative cache over a direct mapped cache?

More efficient utilization of cache blocks Signup and view all the answers

What is the purpose of the special, costly hardware required in a fully associative cache?

To search all tags in parallel to retrieve data quickly Signup and view all the answers

How does the size of the cache blocks affect the cache design?

All of the above Signup and view all the answers

What is the purpose of the block field in the memory address format?

To map main memory blocks to specific cache blocks Signup and view all the answers

What is the purpose of a victim block in cache memory?

To determine which block to evict from the cache Signup and view all the answers

How does a fully associative cache differ from a direct mapped cache?

In a fully associative cache, each memory reference maps to a set of several cache blocks. Signup and view all the answers

Why is it impossible to implement an optimal replacement algorithm in cache memory?

Optimal replacement algorithms are based on future predictions which are not feasible. Signup and view all the answers

What does a set associative cache mapping allow in terms of memory references compared to direct mapped cache?

Memory references map to a set of several cache blocks. Signup and view all the answers

Why is temporal locality important when selecting a replacement policy for cache memory?

To optimize the efficiency of the cache memory. Signup and view all the answers

What characteristic distinguishes set associative cache from fully associative and direct mapped caches?

Mapping memory references to a set of several cache blocks Signup and view all the answers

Which type of caching involves devising an algorithm to determine which block to evict from the cache?

Fully associative caching Signup and view all the answers

'An optimal replacement policy would be able to look into the future to see which blocks won’t be needed for the longest period of time.' Why is this statement relevant in cache management?

'It helps optimize the efficiency of caching.' Signup and view all the answers

What is the Effective Access Time (EAT) for the given scenario?

$11ns$ Signup and view all the answers

What is the purpose of a victim cache?

To hold recently evicted blocks from the main cache Signup and view all the answers

What is a trace cache?

A variant of an instruction cache that holds decoded instructions for program branches Signup and view all the answers

What is the typical access time for Level 1 cache?

4ns Signup and view all the answers

What is the purpose of an inclusive cache?

To guarantee that all data in a smaller cache also exists at the next higher level Signup and view all the answers

What is the typical size range of Level 2 cache?

64KB to 2MB Signup and view all the answers

What is the purpose of an exclusive cache?

To permit only one copy of the data across all cache levels Signup and view all the answers

What is the typical access time for Level 2 cache?

15ns to 20ns Signup and view all the answers

What is the purpose of cache memory?

To store recently used data closer to the CPU Signup and view all the answers

Which of the following is not a form of locality?

Random locality Signup and view all the answers

In a direct mapped cache, how is the cache block Y determined from the main memory block X?

Y = X % N Signup and view all the answers

What is the purpose of the tag field in a direct mapped cache?

To identify the main memory block that maps to the cache block Signup and view all the answers

In the example with a 4-block main memory and a 2-block cache, which main memory blocks map to the same cache block?

Blocks 0 and 2 Signup and view all the answers

What is the key difference between cache memory and main memory?

Main memory is much larger than cache memory Signup and view all the answers

Which of the following is not a characteristic of the simplest cache mapping scheme, direct mapped cache?

The cache size is always larger than the main memory size Signup and view all the answers

What is the purpose of the offset field in a direct mapped cache address?

To identify the specific byte within a cache block Signup and view all the answers

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.