A computer system implements 8 kilobyte pages and a 32-

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A computer system implements 8 kilobyte pages and a 32- bit physical address space. Each page table entry contains a valid bit, a dirty bit, three permission bits, and the translation. If the maximum size of the page table of a process is 24 megabytes, the length of the virtual address supported by the system is ______ bits.

1. 16
2. 6
3. 64
4. 36

Correct Option: D

Given page size = 8 kb
PAS = 32 – bit

∴ Number of pages =	PAS	=	2³²	= 2¹⁹ frames
	P.S		2¹³

So, it is given that each page table entry contains a valid bit, a dirty bit, 3 permission bits. ⇒ 5 bits are reserved.
∴ It means one entry requires 19 + 5 = 24 bits
∴ Page Table size = n × e
24 × 2²⁰ × 3 = n × (24)

⇒ n =	24 × 2²⁰ × 8	= 2²³ pages
	24

Length of the virtual address = 23 + 13 = 36 bits