Operating Systems: Concurrent and Distributed Software Design

4.9. Process abstraction and implementation

The above sections have shown the details of how processes may be implemented. Figure 4.13 shows two layers: the high-level process abstraction and the layer supporting the abstraction. The function of the support layer is to provide an environment in which concurrent processes may exist. The support layer can be thought of as being at a low level within an operating system, so that processes may be used to execute operating system functions, such as device handlers and the memory management subsystem. Figure 4.14 gives an alternative view of Figure 4.13, showing the process management module as an abstract data type, located within an operating system, see also Figure 4.6. The representation of processes ...