Thread Scheduling Strategies: Preemptive vs Cooperative Quiz

Explore the differences between preemptive and cooperative thread scheduling with this quiz, covering key concepts, behaviors, and scenarios. Gain clarity on multi-threading strategies, resource management, and scheduling mechanisms in computing environments.

  1. Identifying Preemptive Scheduling

    Which thread scheduling strategy allows the operating system to interrupt and switch threads even if the thread does not yield control voluntarily?

    1. Preemptive Scheduling
    2. Passive Scheduling
    3. Thread Pooling
    4. Cooperative Scheduling

    Explanation: Preemptive scheduling allows the operating system to forcibly switch between threads, ensuring fair use of resources. Cooperative scheduling relies on threads yielding control, which is not the case here. Passive scheduling is not a recognized thread scheduling strategy, and thread pooling refers to a resource management technique, not scheduling.

  2. Need for Voluntary Yield

    In which thread scheduling strategy must each thread explicitly yield control to allow other threads to run?

    1. Context Pooling
    2. Preemptive Scheduling
    3. Cooperative Scheduling
    4. Aggressive Scheduling

    Explanation: In cooperative scheduling, a thread keeps running until it voluntarily yields control, which can lead to issues if a thread never yields. Preemptive scheduling does not rely on threads yielding. Aggressive scheduling is not a standard term in this context, and context pooling is unrelated to thread scheduling.

  3. Potential for Starvation

    Which thread scheduling method is more prone to a single thread causing starvation if it fails to yield?

    1. Synchronous Scheduling
    2. Cooperative Scheduling
    3. Preemptive Scheduling
    4. Round Robin Scheduling

    Explanation: Cooperative scheduling is vulnerable to a thread monopolizing CPU time if it doesn't yield, potentially starving others. Preemptive scheduling can prevent this by forcibly switching threads. Round robin is a type of preemptive scheduling, while synchronous scheduling is not a standard scheduling strategy.

  4. Context Switch Timing

    If a system needs to perform a context switch immediately when a thread with higher priority becomes ready, which scheduling strategy is required?

    1. Preemptive Scheduling
    2. Deferred Scheduling
    3. Cooperative Scheduling
    4. Single-Threaded Scheduling

    Explanation: Preemptive scheduling enables immediate context switches based on priority, as the scheduler can interrupt threads as needed. Deferred and single-threaded scheduling are not appropriate here. Cooperative scheduling depends on the running thread to yield, which may not allow immediate context switches.

  5. Impact on System Responsiveness

    Which scheduling strategy tends to provide better system responsiveness, especially in systems with many interactive users or tasks?

    1. Cooperative Scheduling
    2. Silent Scheduling
    3. Preemptive Scheduling
    4. Manual Scheduling

    Explanation: Preemptive scheduling helps maintain consistent responsiveness by allowing the system to interrupt threads and serve new tasks promptly. Cooperative scheduling can lead to delays if threads delay yielding. Silent and manual scheduling are not standard terms in this context.

  6. Programming Responsibility

    Which scheduling strategy places more responsibility on programmers to ensure fair resource sharing between threads?

    1. Dynamic Scheduling
    2. Cooperative Scheduling
    3. Preemptive Scheduling
    4. Time-Shared Scheduling

    Explanation: In cooperative scheduling, programmers must ensure that threads yield regularly, or else some threads may never run. Preemptive scheduling manages fairness at the system level. Dynamic and time-shared scheduling are not thread strategies directly tied to this specific programming responsibility.

  7. Effect on Multithreading Bugs

    Which scheduling approach is more likely to mask concurrency bugs, since threads only yield at predictable places in the code?

    1. Priority Scheduling
    2. Hybrid Scheduling
    3. Cooperative Scheduling
    4. Preemptive Scheduling

    Explanation: Cooperative scheduling can hide concurrency issues, as thread switches only occur at known points, making bugs less apparent. Preemptive scheduling often exposes these bugs by causing unpredictable thread interactions. Hybrid and priority scheduling describe different scheduling focuses that do not specifically address bug masking in this way.

  8. Example Scenario: Deadlock Risk

    If one thread holds a shared resource and refuses to yield in a scheduling strategy, which approach is most likely to result in a deadlock or system freeze?

    1. Cooperative Scheduling
    2. Edge-Based Scheduling
    3. Preemptive Scheduling
    4. Token Scheduling

    Explanation: With cooperative scheduling, a non-yielding thread can prevent other threads from accessing resources, potentially causing a freeze or deadlock. Preemptive scheduling allows forcing switches to avoid such problems. Edge-based and token scheduling are not standard thread scheduling strategies.

  9. Power Consumption Impact

    Which scheduling strategy can potentially help reduce CPU power consumption by minimizing unnecessary context switches?

    1. Cooperative Scheduling
    2. Serial Scheduling
    3. Active Scheduling
    4. Preemptive Scheduling

    Explanation: Cooperative scheduling can minimize context switches, as threads voluntarily yield less frequently, reducing CPU overhead and potentially saving power. Preemptive scheduling may introduce more context switches due to automatic interruptions. Active and serial scheduling do not specifically address power consumption in this way.

  10. Suitability for Real-Time Systems

    Which scheduling strategy is often preferred in real-time systems that require strict timing guarantees and swift task preemption?

    1. Cooperative Scheduling
    2. Semi-Cooperative Scheduling
    3. Intersecting Scheduling
    4. Preemptive Scheduling

    Explanation: Preemptive scheduling is suitable for real-time systems as it allows high-priority tasks to interrupt ongoing threads, meeting timing requirements. Cooperative scheduling cannot guarantee immediate responsiveness. Intersecting and semi-cooperative scheduling are not common strategies in real-time contexts.