CIS343|510                              Chapter Two Review

As an interface between the user and the computer hardware, the operating sytem can be thought of as having three objectives:

1-3.

4. As a user/computer interface, in which of these areas are services not typically provided by the operating system:

a. Mail merge                                      d. User fingerprinting

b. Program creation                             e. Error detection and response

c. Controlled access to files                  f. Design and analysis of algorithms

Identify these services provided by the operating system:

5. Collect usage statistics; monitor performance parameters.

6. Takes care of the details of corresponding with "the outside world".

7. Give user access to programs for editing and debugging programs.

8. Control access to all the resources of the system; provide protection; resolve conflicts for resource contention.

9. Respond to error conditions by clearing the condition with the least amount of impact on running applications.

10. Perform the tasks, such as loading a program into memory, needed in order to run user programs.

11. Handle the details of reading from & writing to files; provide protection mechanisms for these files.

12. A computer system can be thought of as a _____ for movement, storage and processing of data and for the control of these functions.

13. And the chief task of an operating system can defined as _____.

14-15. The above describes the operating system as a control mechanism. In what two ways does the OS differ from most other control mechanisms?

16. The portion of the OS which contains the most frequently-used functions and which resides in main memory is known as the...

17. Which of these are not reasons why major OSs evolve over time?

a. New software purchased by user                d. Hardware upgrades

b. New services desired by user            e. Fixes of bugs in the OS

c. Non-von-Neumann architectures                f. New types of hardware

Identify the stage in the evolution of OSs described below:

18. Jobs are run in batches, but memory holds several jobs at a time.

19. A piece of software called the monitor handles the running of jobs submitted by users.

20. Programmer interacts directly with the computer hardware. Basically, there is no OS.

21. Many users interact with running programs.

22. Match the type of OS in Section A with typical problems / advantages / hardware-software requirements in Section B.

Section A::

          Time-Sharing System

          Serial Processing

          Multiprogrammed Batch Systems

          Simple Batch Systems

Section B::

memory protection

setup time

memory management

contention for resources

job control language

privileged instructions

sign-up sheets to reserve machine time

Identify these hardware features which are desireable for modern operating systems.

23. Facilitates the OS relinquishing and regaining control of the processor.

24. Can be used to prevent a single job from monopolizing the system.

25. Detect attemps by user program to write to OS area of memory.

26. Does not allow user program to execute the full set of machine instructions.

What are the 5 major intellectual achievements in the development of OSs?

27-31.

32. Give a definition of process.

Identify the three major lines of computer system development which gave rise to problems in timing and synchronization, which, in turn, gave rise to the concept of a process.

33. Processor is switched among various programs residing in memory.

34. Support many users simultaneously.

35. Online entry of queries and updates against a database.

Identify these errors in system software which occurred in early attempts to coordinate the various activities mentioned above.

36. Signals needed to coordinate events and routines are lost or duplicate signals are received.

37. Two or more programs make use of a resource which can only be used sequentially (not simultaneously).

38. Unexpected interaction between programs in a shared system, interfering with the operation of one or the other or both.

39. Two or more programs cannot proceed until the other does.

40. Name the three components that comprise a process

With respect to Figure 2.8:

41. Which process is currently executing? Give two ways this answer can be determined.

42. What is the value "b" that is found in the base register?

43. What is the value "h" that is found in the limit register?

44. In what way did a change in hardware provide the solution for a system software problem? What was the software problem? How was the problem solved by hardware?

Identify these principal storage management responsibilities:

45. Programmers should be able to create & destroy modules and alter their size dynamically.

46. Prevent independent processes from interfering with each other.

47. Store information for extended periods of time.

48. Allocate memory across the hierarchy without burden to the programmer.

49. Allow sharing of memory while preventing inappropriate access.

Identify these goals of a resource allocation and scheduling policy

50. Maximize throughput, minimize response time, accommodate as many users as possible.

51. Give all processes approximately equal access to resources.

52. Discriminate among different classes of jobs with different service requirements.