GATE CSE 2009 | Question: 10

Question

The essential content(s) in each entry of a page table is / are

• A. Virtual page number

• B. Page frame number

• C. Both virtual page number and page frame number

• D. Access right information

Comments

Notice It is Page frame number. It is not just Frame Number because in multiple level page table using Frame Number may be little bit confusing.

Refer -> https://gateoverflow.in/490/gate2008-67

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A page table entry contains

 frame number ,Present bit ,Modify bit,valid bit, proaction bit 
Other control bits And, page number is used to index this table.

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what is present bit and proaction bit ,
did you mean protection in place of proaction?

Answer 1

It is (B).

The page table contains the page frame number essentially.

Comments

page number is an index, and index is not stored, just like array index is not stored in array data, its simply implied by its location

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What about virtual page number?

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only frame numbers are essential because virtual page numbers are used as indices of each page table entry..

Answer 2

A page table entry contains

Present bit

Modify bit

Other control bits

And frame number.

And, page number is used to index this table.

Hence, B) is essential anytime.

Comments

page no index to map with corresponding frame no where and how it is stored???

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Both virtual page number and page frame number---------> why it is wrong?

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there is nothing called virtual page number that is saved in page table entry that's why it is wrong @amitqy.