Operating Systems: Concurrent and Distributed Software Design

3.10. Summary

The hardware is one source of events, and therefore of concurrent activity, in a concurrent system. We have seen how the hardware may signal an event, such as the arrival of a unit of data, and how events are handled by software. Hardware events may be classified as those which are caused by (and must be handled synchronously with) a running program and those which are external and may be handled asynchronously.

Some concurrent systems may need to meet timing requirements. For such systems it is necessary to understand how events arrive and the mechanism for handling them. It is also important to realize that, although the hardware may be fast enough to meet timing requirements, software policies could make it impossible to guarantee ...