MadeEasy Test Series: CO & Architecture - Cache Memory

Question

Assume that for a certain processor, main memory access time is 100 nanoseconds and cache memory access time is 20 nanoseconds. Suppose while running a program, it was observed that 25% of the processor’s requests result in a cache miss. What is the average access time in nanoseconds?

A) 75

B) 80

C) 40

D) 45

Comments

option D?

solve using fundamental rule..for finding AAT

Answer 1

option d

avg access time (T)= Time for cache + (miss of cache * time for main memory)

                               = 20ns + (0.25*100ns)

                               =45 ns