Why is set associative cache organization better than direct mapping and fully associative mapping?
Set associative caches generally have lower miss rates than direct mapped caches of the same capacity because they have fewer conflicts. However, set associative caches are usually slower and somewhat more expensive to build because of the output multiplexer and additional comparators.
What are the differences among direct mapping and associative mapping?
Direct mapping maps each block of main memory into only one possible cache line. Associative mapping permits each main memory block to be loaded into any line of the cache.
What are the differences between direct mapped and fully associative caches?
At one extreme is a fully associative cache, in which a new line can be placed at any location in the cache. At the other extreme is a direct mapped cache, in which each cache line has a unique location in the cache to which it will be assigned. Intermediate schemes are called n-way set associative.
Which cache mapping technique is better?
Set associative cache mapping combines the best of direct and associative cache mapping techniques. Usually, the cache memory can store a reasonable number of blocks at any given time, but this number is small compared to the total number of blocks in the main memory.
What is the difference between associative cache memory and content addressable memory?
The cache needs to be much faster than main memory. This approach is more economical than the use of fast memory devices to implement the entire main memory….Differences between associative and cache memory :
| S.No. | Associative Memory | Cache Memory |
|---|---|---|
| 1 | A memory unit access by content is called associative memory. | A fast and small memory is called cache memory. |
Why is a direct mapped cache faster than a fully associative cache?
These are two different ways of organizing a cache (another one would be n-way set associative, which combines both, and most often used in real world CPU). Direct-Mapped Cache is simplier (requires just one comparator and one multiplexer), as a result is cheaper and works faster.
What are the disadvantages of direct and associative cache memory mapping techniques?
Disadvantage of direct mapping: 1. Each block of main memory maps to a fixed location in the cache; therefore, if two different blocks map to the same location in cache and they are continually referenced, the two blocks will be continually swapped in and out (known as thrashing).
Which cache mapping technique is better and why?