MadeEasy Test Series: Operating System - Virtual Memory

Question

Certain computer with paged virtual memory has 4KB pages, a 32 bit byte addressable virtual address space and 30 bit byte addressable physical address space. The system manages an inverted page table. Where each entry includes page number plus 12 overhead bits. What is size of basic inverted page table including page number and overhead bits is?

Answer 1

LA = 32 Bits 

PA = 30 Bits

page size = 4KB = 2^12 

-----------------------------------------LA--------------------------------------------------------------------

20

12

--------------------------------------------PA------------------------------------------------------------------

18

12

page table entry size = 20bits + 12 overhead bits = 32 bits = 4Bytes

in inverted page table , #f entries in PAS = #f entries in Page table

Page table size = 2^18 * 4B = 1MB