Day 01Part 16- Scheduling Queue in Operating System, Job Queue, Ready Queue and Device Queue
Here is a comprehensive breakdown of:
Contents
Day 01 โ Part 16: Scheduling Queues in Operating System
What are Scheduling Queues?
In an operating system, scheduling queues are used to manage processes during their life cycle. At any time, a process is in one of several queues depending on its state.
Types of Scheduling Queues
1โฃ Job Queue
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Contains all processes in the system.
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Includes processes that are:
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New (not yet admitted)
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Waiting for CPU
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Performing I/O
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Think of it as the master list of all jobs submitted to the OS.
2โฃ Ready Queue
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Holds all processes that are ready to execute but are waiting for CPU.
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Managed by the short-term scheduler.
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These are loaded into main memory (RAM).
3โฃ Device Queue (I/O Queue)
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Contains processes waiting for an I/O device (printer, disk, etc.).
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Each I/O device has its own queue.
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Handled by the device scheduler.
Process State Transitions and Queues:
Summary Table:
Queue | Managed by | Purpose |
---|---|---|
Job Queue | Long-term scheduler | Holds all processes |
Ready Queue | Short-term scheduler | Holds processes ready for CPU |
Device Queue | I/O scheduler | Holds processes doing I/O |
Quiz: Test Your Understanding
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A process is moved from the ready queue to CPU. What is this action called?
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A) Interrupt
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B) Dispatch
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C) Admit
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D) Block
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Which queue holds processes waiting for I/O?
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A) Job Queue
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B) Ready Queue
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C) Device Queue
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D) None
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GATE Tip:
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Questions often ask โWhich queue does a process move to after an I/O request?โ
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Answer: Device Queue
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Also expect diagrams, state transitions, and MCQs on scheduler types.
Would you like:
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A video explanation script? -
GATE-level MCQs PDF? -
Interactive flowchart or animation for learning?
Let me know how youโd like to continue!