Answers to

Quiz - Chapter Three

CIS343

(1-7) Identify the process states described below:

1. The process cannot execute until some event occurs.

Blocked

2. The process is in secondary memory and is available for execution (as soon as it is loaded into main memory).

Ready, suspend

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

Exit

4. The process is currently being executed.

Running

5. The process has been created but has not yet been admitted to the pool of executable processes.

New

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

Blocked, suspend

7. The process is prepared to execute.

Ready

(8-18) Identify the types of events which lead to the state transitions listed.

8. Null Þ New

A new process is created to execute a program

9. New Þ Ready

OS is prepared to take on an additional process

10. Ready Þ Running

time to select a new process to run

11. Ready Þ Exit

child process is terminated by parent process

12-14. Running Þ Ready (3 answers)

process voluntarily gives up the processor

process’s quantum has expired

OS preempts a process for one of higher priority

15. Running Þ Blocked

process requests something it must wait for

16. Running Þ Exit

process has completed or it aborts

17. Blocked Þ Exit

child process is terminated by parent process

18. Blocked Þ Ready

event process is waiting for occurs

(19-23) Identify these reasons for process termination.

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

privileged instruction

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

running.

normal completion

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

arithmetic error

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

access.

bounds violation

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

memory unavailable

24. Which of the states in Figure 3.8(b) (the 7-state process model) represent processes which have been allocated main memory?

Ready, Running, Blocked

25. Which represent processes currently in secondary memory?

Blocked/Suspend

Ready/Suspend

New

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

process control block

(27-29) Identify these mechanisms for interrupting the execution of a process:

27. An error or exception condition is generated by the process

trap

28. Process requests on OS service

supervisor call

29. Due to an event, such as completion of I/O operation, that is external

to the process

interrupt

30-35. Draw the diagram of the 5-state process model, labeling all the nodes and arcs.

{Use letters from the Word Bank for labeling}

See Stallings Fig. 3.5, p. 115

New

Ready

Running

Exit

Blocked

Admit

Dispatch

Time-out

Release

Event Wait

Event Occurs