Page replacement algorithms (FIFO, LRU, Optimal) in Operating Systems - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to identify the page replacement algorithm that removes the oldest page first.

Operating Systems

algorithm = "[1]"  # This algorithm replaces the oldest page in memory first.

Drag options to blanks, or click blank then click option'

ARandom

BLRU

CFIFO

DOptimal

Attempts:

3 left

💡 Hint

Common Mistakes

Confusing FIFO with LRU which removes least recently used pages.

Choosing Optimal which requires future knowledge.

FIFO stands for First-In-First-Out. It replaces the oldest page in memory first, regardless of how often or recently it was used.

2fill in blank

medium

Complete the code to identify the algorithm that replaces the page which will not be used for the longest time in the future.

Operating Systems

algorithm = "[1]"  # This algorithm requires future knowledge of page references.

Drag options to blanks, or click blank then click option'

AOptimal

BFIFO

CLRU

DClock

Attempts:

3 left

💡 Hint

Common Mistakes

Choosing LRU which uses past usage, not future.

Confusing with FIFO which uses arrival order.

Optimal page replacement algorithm replaces the page that will not be used for the longest time in the future. It is theoretical and requires future knowledge.

3fill in blank

hard

Fix the error in the description of the algorithm that replaces the least recently used page.

Operating Systems

algorithm = "[1]"  # This algorithm replaces the page that was used the longest time ago.

Drag options to blanks, or click blank then click option'

AFIFO

BLRU

COptimal

DRandom

Attempts:

3 left

💡 Hint

Common Mistakes

Confusing LRU with FIFO which removes oldest loaded page.

Choosing Optimal which requires future knowledge.

LRU stands for Least Recently Used. It replaces the page that has not been used for the longest time.

4fill in blank

hard

Fill both blanks to complete the sentence describing FIFO and LRU algorithms.

Operating Systems

The [1] algorithm replaces pages in the order they were loaded, while the [2] algorithm replaces pages based on least recent usage.

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AFIFO

BOptimal

CLRU

DClock

Attempts:

3 left

💡 Hint

Common Mistakes

Mixing up FIFO and LRU in the sentence.

Choosing Optimal which is not described here.

FIFO replaces pages in the order they were loaded (oldest first). LRU replaces pages based on least recent usage.

5fill in blank

hard

Fill all three blanks to complete the dictionary that maps algorithm names to their key characteristics.

Operating Systems

algorithms = {"FIFO": "[1]", "LRU": "[2]", "Optimal": "[3]"}

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Aremoves oldest page

Bremoves least recently used page

Cremoves page not used for longest future time

Dremoves random page

Attempts:

3 left

💡 Hint

Common Mistakes

Mixing up the descriptions of LRU and Optimal.

Choosing random page removal which is not part of these algorithms.

This dictionary maps each algorithm to its main page replacement strategy: FIFO removes the oldest page, LRU removes the least recently used page, and Optimal removes the page not used for the longest time in the future.