Scheduling Criteria

operating-systems scheduling

Definition

Scheduling Criteria

Scheduling criteria are dimensions used to select a scheduling algorithm, categorised by user vs. system focus and performance vs. qualitative nature.

Category	Performance-Related	Other (Qualitative)
User-Oriented	Response Time: Delay for user input Turnaround Time: Time to finish Deadlines: Completion constraints	Predictability: Consistency of response times
System-Oriented	Throughput: Processes per hour Processor Utilisation: CPU busy time	Fairness: Equal CPU share Resource Balance: Busy I/O devices Priorities: Importance levels

Trade-offs

User vs. System

Minimising response time (e.g., Round Robin with small quanta) may decrease throughput due to high context switch overhead.

Fairness vs. Throughput

FCFS is fair by arrival order but can cause poor throughput via the convoy effect when long processes block I/O-bound ones.

Predictability vs. Performance

Real-time systems often sacrifice absolute performance to ensure predictable execution and deadline compliance.