Question

Suppose the time to service a page fault is on the average 10 milliseconds, while a memory acces takes 1 mircosecond. Then a 99.99% hit ratio results in a average memory access time of

Answer 1

Average memory access time = [(% of page miss) *(time of service a page fault)+(% of page hit)* (memory access time )]/100

So, average memory access time in microseconds is

(99.99 * 1 + 0.01 * 10 * 1000)/100
= (99.99 + 100)/1000
= 199.99 /1000
= 1.9999 $\mu$ sec