Suppose after analyzing a new cache design, you discover that the cache has far too many conflict misses and this needs to be resolved. You know that you must increase associativity in order to decrease the number of cache misses. What are the implications of increasing associativity?
Answers
Answer:
D
Explanation:
If we are going to increase associativity, in the sense we are going to increase the number of lines in given set, so if we are not fixing block size then bits required to represent block size will be increased.
The second thing is if we are fixing block size, we are increasing the number of lines in block size, then the number of sets will decrease, this effect will go on the number of tag bits required, these bits will increase.So Number of tag bits will increase.
The third thing is, on increasing associativity., already said above, that number of sets will decrease, So in order to search a set, it will not much time., but within the set, there will be more lines because of increasing associativity, to search block request in the worst case, we might end up to search the whole set. This will create an impact on cache access time.
Answer:
Implications of increasing associativity are as follows:
(a) Slower cache access time
(b) Increase index bits
(c) Increase block size
Explanation:
If we are moving to expand associativity, in the sense we are moving to expand the number of lines in a given set, so if we are not specifying block size then bits needed to describe block size will be improved.
The second thing exists if we are setting block size, we are expanding the number of lines in block size, then the number of sets will decline, this effect will go on the number of tag bits needed, and these bits will grow. So the Number of tag bits will increase.
The third thing exists, on improving associativity, as already stated above, the number of sets will decline, So to searching a set, will not much time, but within the set, there will be more lines because of increasing associativity, to explore block requests in the worst case, we might finish up exploring the entire set. This will make an effect on cache access time.
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