
252 Chapter 4 Processes and Operating Systems
results suggest the situation in a single-processor system. They generated 100
random task graphs and generated schedules for each. They varied two design
parameters: the time of the interrupt service time and the context-switching
time. They also adjusted the deadlines of the tasks to provide varying amounts
of slack: no slack, 10% slack, 20% slack, and 40% slack. The results are shown
in Figure 4-15. In each plot, the system rapidly changes from highly schedulable
in the region with small interrupt service and context-switching times, to
unschedulable in the region with large interrupt service and co