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Determine the number of page faults when references to pages occur is the order – 1, 2, 4, 5, 2, 1, 2, 4. Assume that the main memory can accommodate 3 pages and the main memory already has the pages 1 and 2, with page 1 having brought earlier than page 2. (assume LRU i.e. Least-Recently-Used algorithm is applied)

Determine the number of page faults when references to pages occur is the order – 1, 2, 4, 5, 2, 1, 2, 4. Assume that the main memory can accommodate 3 pages and the main memory already has the pages 1 and 2, with page 1 having brought earlier than page 2. (assume LRU i.e. Least-Recently-Used algorithm is applied) Correct Answer 4

Concept:

Least Recently Used (LRU) is a page replacement technique that replaces the least recently used page first from the frame in case of a page miss.

Explanation:

Page reference: 1, 2, 4, 5, 2, 1, 2, 4

Page replacement algorithm: Least Recently Used (LRU)

Frames

1

1

2

4

5

5

1

2

2

4

5

2

1

2

 

4

 5

2

1

2

4
    M M   M   M

LRU = 4 miss = 4-page faults

Related Questions

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