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7. Scheduling Algorithms (2)

Priority Scheduling

Unlike the Round Robin approach, priority scheduling is trying to take account of the relative priority of the jobs in the queue

Consider two of the jobs sitting in the READY queue: Process 1 and Process 4.

Consider the two Process Control Blocks below for Process 1 and Process 4 that are sitting in the READY queue

With a priority scheduling algorithm, Process 1 would be the next to run because it has a higher priority than Process 4

This approach is very good for making sure that the most vital jobs get to run first, However, it must also deal with low-priority jobs, otherwise they may never get a look-in. In this case the scheduler may start to bump up the priority of lower jobs to ensure they will eventually run.