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📝 LRU approximation page replacement

📖 From Operating System • 9. Virtual Memory • 21 questions available

Practice MCQs for LRU approximation page replacement. Test your knowledge with carefully crafted questions across easy, medium, and hard difficulty levels.

🔄 Last updated: 2026-07-26

6
Easy Questions
8
Medium Questions
7
Hard Questions

📝 Sample Questions

Q1. What does the valid bit indicate when it is set to “valid” in a demand‑paging system?

🔹 A. The page is illegal and resides on disk
🔹 B. The page is legal and currently in memory
🔹 C. The page is illegal but cached
🔹 D. The page is free and can be allocated

💡 Difficulty: easy | ✅ Correct: B

Q2. Which hardware structure is commonly used to track recent page references for LRU approximation?

🔹 A. Translation Lookaside Buffer (TLB)
🔹 B. Reference (or use) bit in the page‑table entry
🔹 C. Interrupt Descriptor Table
🔹 D. Stack Pointer Register

💡 Difficulty: medium | ✅ Correct: B

Q3. In the second‑chance (clock) algorithm, what is the purpose of the reference bit?

🔹 A. To indicate whether the page has been modified since it was loaded
🔹 B. To record the time of the last write operation
🔹 C. To show if the page has been accessed recently, allowing the algorithm to give it another chance before eviction
🔹 D. To store the physical frame number of the page

💡 Difficulty: hard | ✅ Correct: D

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🔗 Related Topics

📝 Basic concepts of Demand Paging📝 Performance of demand paging📝 Copy on Write in virtual Memory📝 Basic page replacement in virtual Memory📝 FIFO page replacement
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