4 way set associative cache of 64 KB is used in a system with 32 bits address.…
2026
4 way set associative cache of 64 KB is used in a system with 32 bits address. The 32 bits address is subdivided into TAG, INDEX and BLOCK OFFSET. No. of bits in TAG is:
- A.
19
- B.
18
- C.
20
- D.
21
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Correct answer: B
Cache size is 64 KB (2^16 bytes) with 4-way associativity. Address bits are 32.
Index bits + Offset bits = log2(Cache Size) - log2(Associativity) = 16 - 2 = 14 bits.
Tag bits = Address - (Index + Offset) = 32 - 14 = 18 bits.