Operating System MCQs

Round robin rotates through the ready queue and gives each process up to one time quantum.
It is widely used for time-sharing because it provides regular opportunities to run.

A very small quantum causes the processor to switch processes frequently.
The resulting overhead can consume a significant portion of CPU time.

Priority scheduling bases selection on a priority value rather than only arrival order or burst length.
It may be preemptive or nonpreemptive depending on the system design.

Starvation is indefinite postponement caused by repeatedly favoring other processes.
Priority scheduling can exhibit this problem without a fairness mechanism.

Aging raises the priority of a process as its waiting time increases.
Eventually, the process becomes important enough to receive CPU service.

Waiting time is the accumulated delay while a process is ready but not running.
It excludes time spent executing on the CPU or blocked for I/O.

Response time measures the delay from a request until the system produces the first observable response.
It is especially important for interactive and time-sharing systems.

Preemptive scheduling permits the kernel to interrupt a running process and reassign the processor.
This supports responsiveness and priority enforcement but adds synchronization and switching concerns.

A nonpreemptive scheduler does not forcibly remove the processor from a running process.
The scheduling decision is deferred until the process exits the CPU or enters a waiting state.

A CPU-bound process spends most of its time executing computations and has relatively long CPU bursts.
An I/O-bound process instead performs frequent I/O and usually has shorter CPU bursts.

CPU utilization indicates how effectively the processor is kept busy with productive execution.
It is a percentage rather than a per-process completion delay.

Throughput is the number of processes or jobs completed per unit of time.
It evaluates total system productivity rather than the delay of one particular job.