OS Process Scheduling Q & A #5

Question: What are the different principles which must be considered while selection of a scheduling algorithm?

Answer: The objective/principle which should be kept in view while selecting a scheduling policy are the following −

1. Fairness − All processes should be treated the same. No process should suffer indefinite postponement.

2. Maximize throughput − Attain maximum throughput. The largest possible number of processes per unit time should be serviced.

3. Predictability − A given job should run in about the same predictable amount of time and at about the same cost irrespective of the load on the system.

4. Maximum resource usage − The system resources should be kept busy. Indefinite postponement should be avoided by enforcing priorities.

5. Controlled Time − There should be control over the different times −

   • Response time

   • Turnaround time

   • Waiting time

   The objective should be to minimize above mentioned times.