Chapter 4

Question 1

Limiting the number of threads helps avoid exhausting system resources is a benefit of ………….

Answer 1

Thread pool

Question 2

In one-to-one model, Multiple threads can run in parallel on multi-core systems (T/F)

Answer 2

True

Question 3

A thread comprises a thread ID, a PC, a …………, and a stack

Answer 3

register set

Question 4

In …………, Each task is mapped to a separate thread using the many-to-many model

Answer 4

implicit threading

Question 5

Process threads share code section, ……….. , and resources

Answer 5

data section

Question 6

Most operating systems use the ………….. model

Answer 6

one-to-one

Question 7

……………: Thread creation has less overhead than process creation
(Benefits of Multithreaded Programs)

Answer 7

Economy

Question 8

Process threads share ………, data section, and resources

Answer 8

code section

Question 9

Cancellation of a target thread can be asynchronous or deferred
(T/F)

Answer 9

True

Question 10

In Many-to-Many model, Multiple threads can run in parallel on multi-core systems
(T/F)

Answer 10

True

Question 11

Does not suffer from the drawback of the many-to-one model is an advantage of Many-to-Many Model
(T/F)

Answer 11

True

Question 12

Implicit fork-join is a synchronous version of the ……….

Answer 12

Thread pool

Question 13

In Many-to-one model, The entire process will block if a thread makes a blocking system call (T/F)

Answer 13

True

Question 14

……………: Threads can run in parallel on a multiprocessor machine
(Benefits of Multithreaded Programs)

Answer 14

Scalability

Question 15

Distribution of data across multiple cores

Answer 15

Data parallelism

Question 16

………………: Ensure that these tasks perform equal work of equal value
(Multi-core Programming
Challenges)

Answer 16

Balance

Question 17

In …………, When the server receives a request, it submits it to the pool

Answer 17

Thread pool

Question 18

In one-to-one model, When a thread makes a blocking system call, another thread cannot run (T/F)

Answer 18

False

Question 19

In …………, A library manages the creation of threads and assigns tasks to those threads

Answer 19

Implicit fork-join

Question 20

In one-to-one model, multiple threads can access the kernel at a given time
(T/F)

Answer 20

True

Question 21

………… is a synchronous version of the thread pool

Answer 21

Implicit fork-join

Question 22

In Many-to-Many model, only one thread can access the kernel at a given time
(T/F)

Answer 22

False

Question 23

In ………….., If the pool has a thread, the request is served immediately

Answer 23

Thread pool

Question 24

In ………….., Once a thread completes serving the request, it returns to the pool

Answer 24

Thread pool

Question 25

In asynchronous cancellation, One thread immediately terminates the target thread (T/F)

Answer 25

True

Question 26

A traditional process has a ........ thread of control

Answer 26

single

Question 27

.............. Helps developing modern applications with hundreds of threads

Answer 27

implicit threading

Question 28

.............. are managed without OS support

Answer 28

user threads

Question 29

Developers identify tasks and the library maps them to ........... threads (User / kernel)

Answer 29

Kernel

Question 30

In Many-to-one model, Threads can run in parallel on multi-core systems (T/F)

Answer 30

False

Question 31

A .............. can adjust the number of threads in the pool

Answer 31

dynamic thread pool

Question 32

In ................, If the pool is empty, the task is queued until a thread becomes free

Answer 32

Thread pool

Question 33

In ............., checking whether the target should terminate allows the target thread to terminate itself in an orderly fashion

Answer 33

Deferred cancellation

Question 34

In .............., Threads are not constructed but parallel tasks are designated

Answer 34

Implicit fork-join

Question 35

A ............ process can perform one task at a time

Answer 35

single-threaded

Question 36

In two-level model, No need to limit the number of kernel threads on modern multicore systems (T/F)

Answer 36

True

Question 37

..............: A blocked thread doesn’t block the process (Benefits of Multithreaded Programs)

Answer 37

Responsiveness

Question 38

It is very easy to implement the many-to-many model (T/F)

Answer 38

False

Question 39

In ..............., Run-time libraries (not programmers) create and manage threads

Answer 39

implicit threading

Question 40

In .................., Programmers identify tasks (not threads) that can run in parallel

Answer 40

implicit threading

Question 41

In ............., The target thread periodically checks whether it should terminate

Answer 41

Deferred cancellation

Question 42

............... works well for asynchronous (independent) tasks

Answer 42

Thread pool

Question 43

.................: Threads share the resources of the process (Benefits of Multithreaded Programs)

Answer 43

Resource sharing

Question 44

A ..... comprises a thread ID, a PC, a register set, and a stack

Answer 44

thread

Question 45

................ works well for tasks that are synchronous (cooperating)

Answer 45

Fork-join

Question 46

In traditional ..............., the main parent thread create one or more child threads

Answer 46

Fork-Join

Question 47

In ................., The number of threads that can be created has no upper bound

Answer 47

explicit threading

Question 48

In Many-to-Many Model, Increasing the number of user threads does not affect system performance (T/F)

Answer 48

True

Question 49

Distribution of tasks across multiple cores

Answer 49

Task parallelism

Question 50

In ......... threading, the server creates a thread for each request

Answer 50

Explicit

Question 51

In Many-to-one model, Thread management is done in OS space by a thread library not user (T/F)

Answer 51

False

Question 52

...........: Testing a program with many execution paths (Multi-core Programming Challenges)

Answer 52

Testing and debugging

Question 53

In traditional ..............., the main parent thread wait for the created threads (children) to terminate

Answer 53

Fork-Join

Question 54

In ..................., The programmer writes a task as a function

Answer 54

implicit threading

Question 55

...............: Divide data between tasks that run on separate cores (Multi-core Programming Challenges)

Answer 55

Data splitting

Question 56

...............: Examine data to find dependencies between tasks (Multi-core Programming Challenges)

Answer 56

Data dependency

Question 57

A .......... is a single sequence of execution

Answer 57

Thread

Question 58

In ..........., Each new request requires creating a new thread

Answer 58

explicit threading

Question 59

In Many-to-one model, Only ........ user thread can access the kernel at a time

Answer 59

one

Question 60

In Many-to-Many model, OS creates a set of kernel threads (less than or equal to user threads) (T/F)

Answer 60

True

Question 61

In one-to-one model, OS creates a kernel thread per user thread (can burden performance) (T/F)

Answer 61

True

Question 62

In ...................., The thread is discarded once it has completed its work

Answer 62

explicit threading

Question 63

A ........ is the basic unit of CPU

Answer 63

thread

Question 64

In ....................., Too many threads that work concurrently can exhaust system resources

Answer 64

explicit threading

Question 65

............. are supported and managed directly by the OS

Answer 65

Kernel threads

Question 66

In Many-to-Many model, When a thread makes a blocking system call, another thread can run (T/F)

Answer 66

True

Question 67

.............: divide program into tasks that can run in parallel (Multi-core Programming Challenges)

Answer 67

Identifying tasks

Question 68

Serving a request with an existing thread is faster than creating a thread is a benefit of ..............

Answer 68

Thread pool

Question 69

Does not suffer from the drawback of the one-to-one model is a disadvantage of Many-to-Many Model (T/F)

Answer 69

False

Question 70

A thread comprises a thread ID, a PC, a register set, and a .........

Answer 70

stack

Question 71

Refers to terminating a thread before it has completed

Answer 71

Thread Cancellation

Question 72

In ............., One thread immediately terminates the target thread

Answer 72

Asynchronous cancellation

Question 73

In traditional ..............., the main parent thread join the threads, at which point it can retrieve and combine their results

Answer 73

Fork-Join

Question 74

Modern concurrency libraries use the .............. model

Answer 74

many-to-many

Question 75

A ........ process can perform multiple tasks at a time

Answer 75

multi-threaded