Consider a cache with 32-bit addresses, 768 blocks, and a block size of 128…
Consider a cache with 32-bit addresses, 768 blocks, and a block size of 128 bytes. Tags are 17 bits. How many sets are there, and what is the associativity of the cache?
Answer: B. 256 sets, 3-way set associativity. — Tag = 17 bits Block size = 2^7 bytes i.e. 7 bits for word offset Index bits = Total address bits - (Tag bits + Word offset bits) =32-(17+7) = 8 bits Hence,…
- A.
128 sets, 6-way set associativity.
- B.
256 sets, 3-way set associativity.
- C.
128 sets, 8-way set associativity.
- D.
Data inadequate
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Correct answer: B
Tag = 17 bits
Block size = 2^7 bytes
i.e. 7 bits for word offset
Index bits = Total address bits - (Tag bits + Word offset bits) =32-(17+7) = 8 bits
Hence, Number of sets = 2^8 sets = 256 sets
And, Total 768 blocks makes 768/256 = 3 way set associative.