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Module 6: I/O & File Management

20239m

Suppose that a disk drive has 5000 cylinders, numbered 0 to 4999. The drive is currently serving a request at cylinder 2150, and the previous request was at cylinder 1805. The queue of pending requests, in FIFO order, is:
2069; 1212; 2296; 2800; 544; 1618; 356; 1523; 4965; 3681.
Starting from the current head position, what is the total distance (in cylinders) that the disk arm moves to satisfy all the pending requests for FCFS, SCAN and C-SCAN disk-scheduling algorithms? Draw the head movement diagram also.

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