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This criterion also involves medium-term and long-term scheduling. That will underutilize stressed resources should be favored. The scheduling policy should keep the resources of the system busy. When processes are assigned priorities, the scheduling policy should favor In the absence of guidance from the user or other system-supplied guidance, processes should be treated the same, and no process should suffer starvation. In single-user systems and in some other systems, such as real-time systems, this criterion is less important than some of the others. Shared system, this is a significant criterion. This is the percentage of time that the processor is busy. This clearly depends on the average length of a process but is also influenced by the scheduling policy, which may affect utilization. This is a measure of how much work is being performed. The scheduling policy should attempt to maximize the number of processes completed per unit of time. It may signal a wide swing in system workloads or the need for system tuning to cure instabilities A wide variation in response time or turnaround time is distracting to users. When process completion deadlines can be specified, the scheduling discipline should subordinate other goals to that of maximizing the percentage of deadlines met.Ī given job should run in about the same amount of time and at about the same cost regardless of the load on the system.

Thus, this is a better measure than turnaround time from the user’s point of view Often a process can begin producing some output to the user while continuing to process the request. This is an appropriate measure for a batch job.įor an interactive process, this is the time from the submission of a request until the response begins to be received. Includes actual execution time plus time spent waiting for resources, including the processor. This is the interval of time between the submission of a process and its com- pletion.