Consider a memory system with the following parameters Tc 1

Consider a memory system with the following parameters:

T_c = 100 ns

T_m = 1200 ns

C_c = 10^-4 $/bit

C_m = 10^-5 $/bit

If the effective access time is 10% greater than the cache access time, what is the hit ratio of H?

Solution

Effect Access Time is Te = H x Tc + (1 - H)(Tm + Tc),

In our problem,

Tc = 10ns

Te = 1/1 x Tc

Tm = 1200ns.

Substituting the values in the formula we get,

(1.1) x (10) = H x 10 + (1 – H) (1200 + 10)

11 = 10H + 1210 – 1210H

11 = 1210  – 1200H

1200H = 1210  – 11

H = 1199/1200

H = 0.999999 is the hit ratio of H.