MIDTERM Examination #1

MIDTERM Examination #1

operating system concepts

03-60-330-01 Winter 2010

University of Windsor

School of Computer Science

Please read carefully before you start

1.  This is a CLOSED book test; no notes, textbooks, calculators or computer aids are allowed.
2.  PRINT your name legibly and clearly with your Student ID in the spaces indicated on the Scantron sheet.
3.  You will be asked to sign your name once before leaving the exam room (sign-out). By doing so you state agreement to the terms below
I agree to the above terms and will neither receive nor give unauthorized help on this exam.
4.  All questions are multiple choice. Circle the single response which best answers each question.
5.  Place all responses on the approved Scantron marking sheet using PENCIL.
6.  You are not allowed to give or receive unauthorized help with your test. Any misconduct, as outlined by the Senate bylaw 31 article I, will be reported accordingly.
7.  You have 75 minutes to complete this test.
8.  You may keep this question paper following the examination. A photocopy of your Scantron sheet will be returned to you.
9.  The maximum mark is 64.
Good Luck!

ANSWER SHEET

All questions are Multiple Choice or True/False. In each Multiple Choice question, 4 responses are provided – you are to choose only one response which best answers the question. Use the Scantron sheet provided to indicate your answers. Circle the letter A, B, C or D (one only). For True/False types of questions, circle either A or B. If an error is made you must carefully erase the error and then fill in the circle you intend to choose.

USE PENCIL ONLY ON THE SCANTRON SHEET

1. / A circular queue is the most appropriate data structure for ______scheduling.
A) / RR
B) / FCFS
C) / SJF
D) / Multi-level
2. / Turnaround time refers to the amount of time ______.
A) / that CPU utilization is minimized
B) / needed to execute a particular process
C) / a process has been waiting in the ready queue
D) / it takes from when a request was submitted until the first action is produced
3. / ____ is the amount of time a process has been waiting to enter the running state.
A) / Wait time
B) / Response time
C) / Turnaround time
D) / None of these responses are correct.
4. / ____ is the amount of time it takes from when a request was submitted until the first response is produced.
A) / CPU utilization
B) / Response time
C) / Turnaround time
D) / Throughput
5. / ____ is the number of processes that are completed per time unit.
A) / CPU utilization
B) / Response time
C) / Turnaround time
D) / Throughput
6. / The major challenge in designing a layered operating system approach is ____.
A) / making sure each layer is easily converted to modules
B) / making sure that each layer hides certain data structures, hardware, and operations from higher-level layers
C) / appropriately defining the various layers
D) / debugging a particular layer
7. / In multiprocessor environments, two copies of the same data may reside in the local cache of each CPU. Whenever one CPU alters the data, the cache of the other CPU must receive an updated version of this data. This is called Cache ______.
A) / redundancy
B) / integrity
C) / coherency
D) / normalization
8. / Which of the following is considered a resource that may be allocated by an operating system?
A) / CPU
B) / bus
C) / file system
D) / Instruction register
9. / Two important design issues for cache memory are ____.
A) / speed and volatility
B) / size and replacement policy
C) / power consumption and reusability
D) / size and access privileges
10. / Most often, application programs access system resources using ______.
A) / system calls
B) / kernel threads
C) / user threads
D) / application program interfaces
11. / CPU registers are often used to ______.
A) / pass parameters to the operating system
B) / store values for reuse by other user programs
C) / save memory for storing programs
D) / All of the above responses are correct.
12. / The resource pyramid, with CPU registers and cache memories at one point of the pyramid and tape drive storage at an opposite point, reflects which of the following problems of computer design and operating system management?
A) / Resource Allocation
B) / Speed to Cost tradeoff
C) / Volatility to Cost tradeoff
D) / Both B and C responses are correct.
13. / Thread-specific data is data that ____.
A) / is not associated with any process
B) / has been modified by the thread but not yet updated to the parent process
C) / is copied and not shared with the parent process
D) / is generated by the thread independent of the thread's process
14. / The Producer-Consumer problem is related to ______.
A) / the allocation of resources to process states
B) / the scheduling of process states
C) / the handling of process control blocks
D) / All of these responses are correct.
15. / Which of the following is an operating system?
A) / Linux
B) / Solaris
C) / Windows Vista
D) / All of these responses are correct.
16. / Which of the following is an example of a systems program?
A) / command interpreter
B) / Web browser
C) / text formatter
D) / database system
17. / If a program terminates abnormally, a dump of memory may be examined by a ____ to determine the cause of the problem.
A) / module
B) / debugger
C) / shell
D) / control card
18. / In RR scheduling, the time quantum should be ______the context-switch time.
A) / small with respect to
B) / large with respect to
C) / the same size as
D) / irrelevant to
19. / Context switching between processes is carried out by the
A) / dispatcher
B) / short term scheduler
C) / interrupt handler
D) / thread manager
20. / An optimal job scheduling scheme is
A) / RR
B) / FCFS
C) / SJF
D) / Priority
21. / A microkernel is a kernel ____.
A) / that is stripped of all essential components
B) / that is compressed before loading in order to reduce its resident memory size
C) / that is compiled to produce the smallest size possible when stored to disk
D) / containing many components that are optimized to reduce resident memory size
22. / Which of the following pieces of information is least useful to the SYSGEN program of an operating system?
A) / the CPU being used
B) / amount of memory available
C) / what applications to install
D) / operating-system options such as buffer sizes or CPU scheduling algorithms
23. / A ____ circuit can be used to prevent a user program from never returning control to the operating system.
A) / portal
B) / program counter
C) / firewall
D) / timer
24. / Bootstrap programs must be provided using ______.
A) / volatile memory
B) / erasable-programmable memory
C) / non-volatile ROM devices
D) / special magnetic disk tracks
25. / Long-term scheduling is performed ______.
A) / typically on submitted jobs
B) / when processes must be moved from ready to waiting state
C) / on processes in the ready queue
D) / None of the above responses is correct.
26. / Which of the following is true of multilevel queue scheduling?
A) / Processes can move between queues.
B) / Each queue has its own scheduling algorithm.
C) / A queue cannot have absolute priority over lower-priority queues.
D) / It is the most general CPU-scheduling algorithm.
27. / In scheduling, the term Aging involves ______.
A) / higher priority processes preventing low-priority processes from ever getting the CPU.
B) / gradually increasing the priority of a process so that a process will eventually execute.
C) / processes that are ready to run but stuck waiting indefinitely for the CPU.
D) / processes being stuck in ready queues so long that they die.
28. / Medium-term scheduling is performed ______.
A) / typically on submitted jobs
B) / when processes must be moved from waiting to ready state
C) / on processes in the ready queue
D) / None of the above are correct.
29. / An I/O-bound process ______.
A) / spends equal time seeking I/O operations and doing computational work
B) / spends more of its time doing computational work than seeking I/O operations
C) / spends more of its time seeking I/O operations than doing computational work
D) / spends less of its time seeking I/O operations than doing computational work
30. / Processes are capable of ______.
A) / executing concurrently
B) / performing data transfer operations
C) / performing logic
D) / All of the above responses are correct
31. / ____ scheduling is approximated by predicting the next CPU burst with an exponential average of the measured lengths of previous CPU bursts.
A) / Multilevel queue
B) / RR
C) / FCFS
D) / SJF
32. / The ____ of a process contains temporary data such as function parameters, return addresses, and local variables.
A) / text section
B) / data section
C) / program counter
D) / stack
33. / The following are valid process states, including extensions to the 5-state basic model.
A) / Next, Running, Halting
B) / Terminating, Waiting, Threshing
C) / Running, Blocked, Waiting
D) / None of these responses is correct
34. / A CPU-bound process ______.
A) / infrequently requests I/O operations and spends more of its time performing computational work
B) / frequently requests I/O operations and spends more of its time performing computational work
C) / infrequently requests I/O operations and spends less of its time performing computational work
D) / frequently requests I/O operations and spends less of its time performing computational work
35. / A process control block ____.
A) / includes information on the process's state
B) / stores the address of the next instruction to be processed by a different process
C) / determines which process is to be executed next
D) / is an example of a process queue
36. / The lowest cost secondary storage device is ____.
A) / random access memory
B) / DVD ROM
C) / tape drive
D) / magnetic disk
37. / Which of the following is a property of peer-to-peer systems?
A) / Clients and servers are not distinguished from one another.
B) / Separate machines act as either the client of the server but not both.
C) / They do not offer any advantages over traditional client-server systems.
D) / They suffer from the server acting as the bottleneck in performance.
38. / A message passing model is ____.
A) / easier to implement than a shared memory model for inter-computer communication
B) / is faster than the shared memory model
C) / a network protocol and does not apply to operating systems
D) / is only useful for small simple operating systems
39. / An advantage to using a higher-level language to implement an operating system is ______.
A) / the system can be understood by all users
B) / modern computer science students do not learn machine language programming
C) / an operating system is far easier to port to some other hardware if it is written in a higher-level language
D) / Both A and B are correct responses
40. / For a single-processor system ______.
A) / processes spend long times waiting to execute
B) / there will never be more than one running process
C) / input-output always causes CPU slowdown
D) / process scheduling is always optimal
41. / In the context of operating systems, the term Policy ____.
A) / determines how to do something
B) / determines what will be done
C) / is not likely to change across places
D) / is not likely to change over time
42. / The most volatile form of computer storage is ____.
A) / random access memory
B) / CPU registers
C) / tape drive
D) / magnetic disk
43. / The most responsive, or fastest, category of computer storage is ____.
A) / random access memory
B) / CPU registers
C) / DVD/CD-ROM
D) / cache memory
44. / A thread control block ______.
A) / is managed by the parent process
B) / contains the same information as the process control block
C) / has the identical structure as the process control block
D) / does not include information about the parent process resource allocation
45. / The list of processes waiting for a particular I/O device is called a(n) ____.
A) / standby queue
B) / device queue
C) / wait queue
D) / interrupt queue
46. / In a(n) ____ temporary queue, the sender must always block until the recipient receives the message.
A) / zero capacity
B) / variable capacity
C) / bounded capacity
D) / unbounded capacity
47. / Marshalling refers to ______.
A) / packaging parameters in a form suitable for network transmission
B) / initiating a remote procedure call to a networked computer
C) / leading the packet train in TCP/IP messaging
D) / ordering processes in state queues
48. / A program file is ______.
A) / another name for a process
B) / an active entity
C) / a passive entity
D) / All of the above responses are correct.
49. / When a child process is created, which of the following is a possibility in terms of the execution or address space of the child process?
A) / The child process runs concurrently with the parent.
B) / The child process may outlive the parent.
C) / The child may acquire more resources than the parent.
D) / None of the above responses is correct.
50. / The ____ scheduling algorithm is designed especially for time-sharing systems.
A) / SJF
B) / FCFS
C) / RR
D) / Multilevel queue
51. / In a virtual machine, each program believes that it has ____.