Question

Of these two types of programs:a. I/O -bound b. CPU -bound which is more likely to have voluntary context switches, and which is more likely to have nonvoluntary context switches? Explain your answer.

Answer 1

Answer:

For I/O-bound we require voluntary context switches.

For CPU-bound we require non-voluntary context switches.

Explanation:

A voluntary context switches occurs when process has given up control of the CPU because it requires a resource that is currently unavailable(such as blocking for I/O). It happen frequently in normal system operation. Voluntary context switching initiated with a call to the sleep() routine.

A non-voluntary context switches occurs when the CPU has taken away from a process, such as when it's time slice has expired or it has been preempted by a high-priority process. It is forced by direct invocation of the low-level context-switching mechanism embodied in the mi_switch() and setrunnable() routines.