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The
operating system is responsible for using
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hardware
efficiently — for the disk drives, this
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means
fast access time and large disk bandwidth.
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Access
time has two major components
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Seek
time is the time for the disk to move the heads to
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the
cylinder containing the desired sector.
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Rotational
latency is the additional time waiting for the
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disk
to rotate the desired sector to the disk head.
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Minimize
seek time
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Seek
time ~ seek distance
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