1. We can characterize the behavior of an individual process by listing the

sequence of instructions that execute for that process. Such a listing is

referred to as a _____ of the process.

trace

2. Draw the diagram of a 5-state process model, labeling all the arcs.

3. Briefly state a reason for swapping (moving part or all of a process from

main memory to disk).

Because processor is so much faster than I/O it will be common for

all processes in memory to be waiting for I/O.

4. With the use of swapping, one other state must be added to the 5-state

model, namely the _____ state.

suspend

5. The process cannot execute until some event occurs.

Blocked

6. The process is in secondary memory and is available for execution (as

soon as it is loaded into main memory).

Ready, suspend

7. The process has been released from the pool of executable processes.

Exit

8. The process is currently being executed.

Running

9. The process has been created but has not yet been admitted to the pool of

executable processes.

New

10. The process is in secondary memory and awating an event.

Blocked, suspend

11. The process is prepared to execute.

Ready

12. The process attempts to use an instruction reserved for the OS.

privileged instruction

13. The process is terminated by its parent process.

parent request

14. The process executes an OS service call to indicate that it has completed

running.

normal completion

15. The process attempts a prohibited computation (e.g., divide by zero).

arithmetic error

16. A piece of data is of the wrong type, or is not initialized.

data misuse

17. The process has run longer than the specified total time limit.

time limit exceeded

18. The parent process terminates.

parent temination

19. The process attempts to use a resource or file it is not allowed to use, or

to use it in an improper fashion.

protection error

20. The process is teminated by the operator or the OS.

operator or OS intervention

21. The process has waited longer than specified maximum for a certain event

time overrun

22. The process attempts to execute a nonexistent instruction.

invalid instruction

23. The process attempts to access memory location it is not allowed to

access.

bounds violation

24. An error occurs during input or output.

I/O failure

25. The process requires more memory than the system can provide.

memory unavailable

It is an action that OS would not normally take

(see Stallings, p. 123)

27. Which of the states in Figure 3.8(b) represent processes which have been

allocated main memory?

Ready, Running, Blocked

28. Which represent processes currently in secondary memory?

Blocked, suspend & Ready, suspend

29. What is the advantage of the process models of Figure 3.8(a) or (b) over the model of Figure 3.5?

Processes do not sit on memory that they cannot use

31. T/F: The use of virtual memory eliminates the need for swapping (use of the suspend state(s)). Why?

False; virtual memory can collapse if there are too many active

processes

32. The data needed by the OS to control a process is contained in the ...

process control block

33. List the typical elements of a process image.

user data, user program, system stack, pcb

34. List the 3 categories of information contained in the process control

block.

process identification, processor state information,

process control information

35. List the 4 categories of functions performed by the OS kernel.

process mgmt, memory mgmt, i/o mgmt, support functions

36. List 3 mechanisms for interrupting the execution of a process.

interrupt, trap, supervisor call

37. List 3 examples of interrupts.

clock interrupt, i/o interrupt, memory fault

38. List 3 approaches to OS execution.

nonprocess kernel, execution within user process,

process-based OS