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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?

(a) Slower cache access time (b) Increase index bits
(c) Increase block size (d) All of these
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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.

So according to me, option D will be correct...

plz, correct me if  I  m wrong...
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it's just misprint...

no need to rethink..

increasing associativity meaning increasing tag bits (we assume block size fixed as nothing given).

now suppose its k way set associative and no. of tag bits is T..

so we need k comparators each T bits..

now more bits to compare meaning more time

so increase in cache access time.

remember: all k comparators will compare simultaneously

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