4.6. Scheduling: General approaches
When a free processor is available the operating system must select a runnable process (if one exists) to run on it. The scheduling policy of the system deter mines which process is selected.
The mechanisms to effect this policy must be as efficient as possible since they are an overhead on every process, however urgent. The design of the data structures representing processes and the algorithms for inserting and removing processes into and out of them is therefore important. In this section, scheduling policies appropriate for meeting the requirements of systems of different types are discussed.
4.6.1. Unary, binary and general scheduling
In certain cases the selection of the next process to run can be simplified. ...