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Suppose the following disk request sequence (track numbers) for a disk with 100 tracks is given: 45, 20, 90, 10, 50, 60, 80, 25, 70. Assume that the initial position of the R/W head is on track 50. The additional distance that will be traversed by the R/W head when the Shortest Seek Time First (SSTF) algorithm is used compared to the SCAN (Elevator) algorithm (assuming that SCAN algorithm moves towards 100 when it starts execution) is____________ tracks.
    Correct answer is '10'. Can you explain this answer?
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    Suppose the following disk request sequence (track numbers) for a disk...
    Shortest Seek Time First (SSTF) Algorithm vs SCAN (Elevator) Algorithm

    Given Disk Request Sequence: 45, 20, 90, 10, 50, 60, 80, 25, 70
    Initial Head Position: 50
    Total Tracks: 100

    SSTF Algorithm
    - In SSTF algorithm, the R/W head moves to the request closest to its current position.
    - It selects the request with the shortest seek time from the current position of the head.
    - In the given sequence, the R/W head will move in the following sequence: 50, 45, 25, 20, 10, 70, 60, 80, 90.
    - Total distance traversed: 195 tracks.

    SCAN (Elevator) Algorithm
    - In SCAN algorithm, the R/W head moves in one direction (towards 100 in this case) until it reaches the last request in that direction, and then it moves in the opposite direction until it reaches the last request in that direction.
    - In the given sequence, the R/W head will move in the following sequence: 50, 60, 70, 80, 90, 100, 10, 20, 25, 45.
    - Total distance traversed: 195 tracks.

    Additional Distance Traversed by R/W Head
    - The additional distance traversed by the R/W head when the SSTF algorithm is used compared to the SCAN algorithm can be calculated by subtracting the total distance traversed in the SCAN algorithm from the total distance traversed in the SSTF algorithm.
    - Additional distance traversed: 195 - 185 = 10 tracks.

    Therefore, the additional distance traversed by the R/W head when the Shortest Seek Time First (SSTF) algorithm is used compared to the SCAN (Elevator) algorithm (assuming that SCAN algorithm moves towards 100 when it starts execution) is 10 tracks.
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    Suppose the following disk request sequence (track numbers) for a disk with 100 tracks is given: 45, 20, 90, 10, 50, 60, 80, 25, 70. Assume that the initial position of the R/W head is on track 50. The additional distance that will be traversed by the R/W head when the Shortest Seek Time First (SSTF) algorithm is used compared to the SCAN (Elevator) algorithm (assuming that SCAN algorithm moves towards 100 when it starts execution) is____________ tracks.Correct answer is '10'. Can you explain this answer?
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    Suppose the following disk request sequence (track numbers) for a disk with 100 tracks is given: 45, 20, 90, 10, 50, 60, 80, 25, 70. Assume that the initial position of the R/W head is on track 50. The additional distance that will be traversed by the R/W head when the Shortest Seek Time First (SSTF) algorithm is used compared to the SCAN (Elevator) algorithm (assuming that SCAN algorithm moves towards 100 when it starts execution) is____________ tracks.Correct answer is '10'. Can you explain this answer? for GATE 2024 is part of GATE preparation. The Question and answers have been prepared according to the GATE exam syllabus. Information about Suppose the following disk request sequence (track numbers) for a disk with 100 tracks is given: 45, 20, 90, 10, 50, 60, 80, 25, 70. Assume that the initial position of the R/W head is on track 50. The additional distance that will be traversed by the R/W head when the Shortest Seek Time First (SSTF) algorithm is used compared to the SCAN (Elevator) algorithm (assuming that SCAN algorithm moves towards 100 when it starts execution) is____________ tracks.Correct answer is '10'. Can you explain this answer? covers all topics & solutions for GATE 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for Suppose the following disk request sequence (track numbers) for a disk with 100 tracks is given: 45, 20, 90, 10, 50, 60, 80, 25, 70. Assume that the initial position of the R/W head is on track 50. The additional distance that will be traversed by the R/W head when the Shortest Seek Time First (SSTF) algorithm is used compared to the SCAN (Elevator) algorithm (assuming that SCAN algorithm moves towards 100 when it starts execution) is____________ tracks.Correct answer is '10'. Can you explain this answer?.
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