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    Question

    In I/O scheduling, which of the following algorithms

    minimizes seek time but may lead to starvation of requests at the ends of the disk? 
    A First-Come, First-Served (FCFS) Correct Answer Incorrect Answer
    B Shortest Seek Time First (SSTF) Correct Answer Incorrect Answer
    C SCAN (Elevator Algorithm) Correct Answer Incorrect Answer
    D C-SCAN (Circular SCAN) Correct Answer Incorrect Answer
    E LOOK Scheduling Correct Answer Incorrect Answer

    Solution

    The SCAN (Elevator Algorithm) moves the disk arm in one direction, servicing requests in that direction until it reaches the end of the disk, and then reverses direction. While this minimizes seek time by servicing requests in the current direction, it can cause starvation for requests located at the far ends of the disk, particularly if new requests continuously arrive closer to the middle of the disk. This behavior leads to longer wait times for the requests at the extreme ends of the disk. Why Other Options are Incorrect: A) FCFS: FCFS is a simple algorithm that services requests in the order they arrive, without consideration of seek time, and thus avoids starvation but does not minimize seek time. B) SSTF: SSTF selects the closest request to the current position, reducing seek time but also potentially causing starvation for requests far from the current position. D) C-SCAN: C-SCAN operates similarly to SCAN but only moves in one direction, avoiding starvation by providing equal treatment to all disk regions. E) LOOK Scheduling: LOOK is a variant of SCAN that stops moving when there are no more requests in the current direction, reducing the risk of starvation.

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