New RBI Grade B 2025 Notification will come Soon! Enroll Here

    Question

    Which of the following page replacement algorithms is

    considered optimal and aims to minimize the number of page faults? 
    A First-In, First-Out (FIFO) Correct Answer Incorrect Answer
    B Least Recently Used (LRU) Correct Answer Incorrect Answer
    C Optimal Page Replacement Correct Answer Incorrect Answer
    D Second Chance Correct Answer Incorrect Answer
    E Clock Correct Answer Incorrect Answer

    Solution

    The Optimal Page Replacement algorithm is recognized as the best theoretical page replacement strategy as it aims to minimize page faults by replacing the page that will not be used for the longest period in the future. This algorithm requires knowledge of future requests, making it impractical for real-world use, but it serves as a benchmark against which other algorithms are compared. In essence, the optimal algorithm reduces the number of page faults to a minimum because it makes decisions based on the best possible future outcome. In situations where a system employs this strategy, it effectively reduces overhead caused by frequent page faults, enhancing the overall performance of memory management. While it is ideal for academic discussions and theoretical models, its impracticality stems from the necessity of predicting future requests, which is often unfeasible in dynamic and unpredictable real-world environments. Option A (FIFO) - FIFO is simple and easy to implement, but it does not necessarily minimize page faults effectively. It replaces the oldest page regardless of its future usage. Option B (LRU) - Least Recently Used is a practical alternative that approximates optimal replacement by replacing the least recently accessed pages; however, it may still lead to more page faults than the optimal algorithm. Option D (Second Chance) - This algorithm gives pages that have been used recently another chance before they are replaced but does not guarantee the least number of page faults compared to the optimal method. Option E (Clock) - The Clock algorithm is a variation of Second Chance and improves on FIFO's shortcomings, but it similarly does not achieve the optimality that the optimal page replacement algorithm does.

    Practice Next

    Relevant for Exams: