Structure and Functions of Operating Systems

Abstract

The operation of a modern computer cannot be imagined without the employment of an operating system. Even in small real-time computers dedicated to a single task some general parts independent of the specific application can be identified. These auxiliary parts assist in bridging the gap between the mostly rather uncomfortable hardware level and the needs of higher levels induced by the application environments. Furthermore, in many systems there exists the necessity for an additional task. Modern computers perform very fast, much faster than is needed for most applications especially for those with interactive controlling. In order to efficiently use the computer’s power we have to organize the concurrent execution of many more or less independent courses of events. Hence, a number of objectives arises for which solutions have to be offered by the operating system. Some of the major topics can be identified as follows:

• Accepting sets of self-contained units capable of concurrent execution

• Organizing a multiplexed usage of processors

• Supplying facilities for interaction between execution units

• Organizing the competition for system resources

• Organizing access to remote recources (this hints at distributed systems)