CPU scheduling: what is the strategy called when the operating system temporarily suspends logically runnable processes to allocate CPU time fairly or meet responsiveness goals?

Introduction / Context:Schedulers decide which process runs on the CPU at a given moment. Systems that must remain responsive or share the CPU among many tasks often interrupt a running process and switch to another ready process. Understanding this policy is critical for real time design, interactive systems, and general purpose OS behavior.

Given Data / Assumptions:

• Processes are logically runnable, meaning they are in the ready state.
• The OS may suspend a running process before it blocks or finishes.
• We need the term for this class of scheduling policies.

Concept / Approach:

Preemptive scheduling allows the OS to interrupt and switch out a running task, giving the CPU to another ready task. Time slicing and priority based preemption are common mechanisms. Non preemptive policies let a process run until it voluntarily yields, blocks, or completes, which can hurt responsiveness.

Step-by-Step Solution:

Verification / Alternative check:

Classic OS textbooks describe Unix like and modern Windows schedulers as preemptive, using time quanta and priorities to interrupt running processes.

Why Other Options Are Wrong:

• non preemptive: the opposite behavior; no forced suspension.
• shortest job first / first come first served: specific algorithms; SJF can be either, but the described suspension is characteristic of preemption.

Common Pitfalls:

• Assuming preemptive implies unfairness; in fact, it enables fairness and responsiveness when correctly tuned.

Final Answer:

preemptive scheduling.