UGC NET 2020 | Given memory access time as p nano…
Given memory access time as p nanoseconds and additional q nanoseconds for handling the page fault. What is the effective memory access time if a page fault occurs once for every 100 instructions?
Answer:Option I Solution:Given,
Memory Access Time = P nanoseconds,
Page Fault Service Time = q nanoseconds,
one page fault occurs for every 100 instructions
Formula used,
Effective Memory Access Time (EMAT)= Page fault rate * Page fault service time + (1-Page fault rate)* Memory Access time
Calculation,
page fault rate = 1/100 {since,1 page fault occurs for every 100 instructions}
EMAT = 1/100 * q + (1-1/100)* p
= q/100 + p - p/100
= p + q/100 {since, p/100 is too small, we can neglect it}
So, Option(I)is correct.
