Operating Systems: Concurrent and Distributed Software Design

4.5. The process data structure

The operating system must handle many processes and will maintain a data structure holding their descriptors. This could be set up in a number of ways. The aim is that the operating system should be able to choose and run the highest-priority process as quickly as possible. Selecting a process to run on a processor is called process scheduling. The selection policy determines which process will be selected and is effected by the scheduling algorithm. Setting up a process state in the processor's registers is called dispatching. Figure 4.7 shows one possible data structure: an array or table of process descriptors; many alternatives are possible.

Figure 4.7. A possible process structure.