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The
OS maintains a collection of process
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state
queues
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typically
one queue for each state – e.g., ready,
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waiting,
…
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each
PCB is put onto a state queue according to
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its
current state
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as a
process changes state, its PCB is unlinked
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from
one queue, and linked to another
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Process
state and the queues change in
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response
to events – interrupts, traps
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