Question

Given the following word addresses: 3, 180, 43, 2,191, 88, 190, 14, 181, 44, 186, 253

Answer 1

Answer:

A. index bits = 2, tag bits = 2, block offset bits = 1, it is a miss.

B. index bits = 2, tag bits = 1, block offset bits = 0, it is a hit

C. the miss rate is 0

Explanation:

a. number of blocks = 12

number of blocks per set = 3

number of set = number of blocks / number of blocks per set = 12/3 = 4

word size = 24

block size = 2

the block offset = $log_{2}$ block size

   = $log_{2}$ 2 = 1

the index bits = $log_{2}$ number of set = $log_{2}$ 4 = 2

the tag bits = ($log_{2}$ word size) - offset - index = ($log_{2}$ 24) -2 - 1 = 5 -2 - 1 = 2

b. word size = 8

block size = 1

the block offset = $log_{2}$ block size

   = $log_{2}$ 1 = 0

the index bits = $log_{2}$ number of set = $log_{2}$ 4 = 2

the tag bits = ($log_{2}$ word size) - offset - index = ($log_{2}$ 8) -2 - 1 = 3 - 0- 2= 1