Consider a paging hardware with a TLB. Assume that the entire

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Consider a paging hardware with a TLB. Assume that the entire page table and all the pages are in the physical memory. It takes 10 milliseconds to search the TLB and 80 milliseconds to access the physical memory. If the TLB hit ratio is 0.6, the effective memory access time (in milliseconds) is ___________.

1. 21 ms
2. 72 ms
3. 12 ms
4. 122 ms

Correct Option: D

T_ave = H₁ × (T_TLB + T_M) + (1 – H₁) × (T_TLB + 2 × T_M)
T_TLB = 10 ms
T_M = 30 ms
H₁ = 0.6
T_ave = 0.6 X (10 + 80) + (1 – 0.6) (10 + 2X80) = 0.6 X 90 + 0.4 X 170 = 122 ms