Galvin Edition 9 Exercise 8 Question 25 (Page No. 393)

Question

Consider a paging system with the page table stored in memory.

a. If a memory reference takes 50 nanoseconds, how long does a paged memory reference take ?

b. If we add $TLBs$, and 75 percent of all page-table references are found in the $TLBs$, what is the effective memory reference time ? (Assume that finding a page-table entry in the $TLBs$ takes 2 nanoseconds, if the entry is present.)

Answer 1

EMAT =  .75(2 + 50) + .25(2 +50 + 50) = 64.5 ns