Question

1. Given the process state diagram, explain what might cause a process to change from Executing to Ready via an interruption?

2. Given the process state diagram, explain what the difference between waiting for a resource vx. waiting for I/O is?

3. What is the context switch?

4. Write an equation to represent the total time taken for a process to complete, including process time and I/O time?

Answer 1

Answer 1:

It Possible in three conditions

a. When Time quantum expires then process goes from running to ready state.

b. When a higher priority process comes then the process (Having low priority) which is currently running changes its state from running to ready.

c. Process is waiting for resource which is currently held by another process.

Answer 2:

Waiting for Resource means Process waiting for external resource which is held by another process and waiting for I/O means Process is completing its input or output operation.

Answer 3:

Storing the context or state of a process so that it can be reloaded when required and execution can be resumed from the same point as earlier is called as Context Switch. This is a feature of a multitasking operating system and allows a single CPU to be shared by multiple processes.

Answer 4:

Equation for Process completion

P_CT=Proc_(T)+I/O_(T)

Here, P_CT is Process completion time

Proc_(T) Process time.(Includes Context switching time and Waiting time)

I/O_(T) Total Input output time.