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In a cache with 64-bytes cache lines, how many bits are used to determine which byte within a cache line an address points to?

In a cache with 64-bytes cache lines, how many bits are used to determine which byte within a cache line an address points to? Correct Answer 6

Concept:

The number of bits used to determine which byte within a cache line an address points to is given by:

N = log2 M

M = Size of the cache lines

Calculation:

log2 64 = 6

∴ The lower 6 bits of the address determine an address’s byte within a cache line

Remember:

The lower bits of the address determines which byte an address refers to within the line that contains it, and only the higher bits in the address need to be sent to the tag array to determine if a hit has occurred.

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