Deck 22: Thread Management and Synchronization in Operating Systems

Question 1

If one thread opens a file with read privileges then___________        

A)other threads in the another process can also read from that file
B)other threads in the same process can also read from that file
C)any other thread can not read from that file
D)all of the mentioned

Answer 1

other threads in the same process can also read from that file

Question 2

The time required to create a new thread in an existing process is___________        

A)greater than the time required to create a new process
B)less than the time required to create a new process
C)equal to the time required to create a new process
D)none of the mentioned

Answer 2

less than the time required to create a new process

Question 3

When the event for which a thread is blocked occurs?

A)thread moves to the ready queue
B)thread remains blocked
C)thread completes
D)a new thread is provided

Answer 3

thread moves to the ready queue

Question 4

The jacketing technique is used to

A)convert a blocking system call into non blocking system call
B)create a new thread
C)communicate between threads
D)terminate a thread

Question 5

Termination of the process terminates

A)first thread of the process
B)first two threads of the process
C)all threads within the process
D)no thread within the process

Question 6

Which one of the following is not a valid state of a thread?

A)running
B)parsing
C)ready
D)blocked

Question 7

The register context and stacks of a thread are deallocated when the thread?

A)terminates
B)blocks
C)unblocks
D)spawns

Question 8

Thread synchronization is required because___________        

A)all threads of a process share the same address space
B)all threads of a process share the same global variables
C)all threads of a process can share the same files
D)all of the mentioned

Question 9

A thread is also called___________        

A)light weight process(lwp)
B)heavy weight process(hwp)
C)process
D)none of the mentioned

Question 10

A thread shares its resources(like data section, code section, open files, signals) with

A)other process similar to the one that the thread belongs to
B)other threads that belong to similar processes
C)other threads that belong to the same process
D)all of the mentioned

Question 11

Resource sharing helps___________        

A)share the memory and resources of the process to which the threads belong
B)an application have several different threads of activity all within the same address space
C)reduce the address space that a process could potentially use
D)all of the mentioned

Question 12

Multithreading on a multi - CPU machine

A)has multiple threads of execution___________        
B)has a single thread of execution
C)can have multiple or a single thread for execution
D)none of the mentioned

Question 13

A process having multiple threads of control implies___________        

A)it can do more than one task at a time
B)it can do only one task at a time, but much faster
C)it has to use only one thread per process
D)none of the mentioned

Question 14

The kernel is___________of user threads.

A)a part of
B)the creator of
C)unaware of
D)aware of

Question 15

Because the kernel thread management is done by the Operating System itself

A)kernel threads are faster to create than user threads
B)kernel threads are slower to create than user threads
C)kernel threads are easier to manage as well as create then user threads
D)none of the mentioned

Question 16

If a kernel thread performs a blocking system call,___________

A)the kernel can schedule another thread in the application for execution
B)the kernel cannot schedule another thread in the same application for execution
C)the kernel must schedule another thread of a different application for execution
D)the kernel must schedule another thread of the same application on a different processor

Question 17

Which of the following is FALSE?

A)context switch time is longer for kernel level threads than for user level threads
B)user level threads do not need any hardware support
C)related kernel level threads can be scheduled on different processors in a multiprocessor system
D)blocking one kernel level thread blocks all other related threads

Question 18

The model in which one kernel thread is mapped to many user-level threads is called

A)many to one model
B)one to many model
C)many to many model
D)one to one model

Question 19

The model in which one user-level thread is mapped to many kernel level threads is called___________        

A)many to one model
B)one to many model
C)many to many model
D)one to one model

Question 20

In the Many to One model, if a thread makes a blocking system call___________        

A)the entire process will be blocked
B)a part of the process will stay blocked, with the rest running
C)the entire process will run
D)none of the mentioned

Question 21

In the Many to One model, multiple threads are unable to run in parallel on multiprocessors because of___________        

A)only one thread can access the kernel at a time
B)many user threads have access to just one kernel thread
C)there is only one kernel thread
D)none of the mentioned

Question 22

The One to One model allows

A)increased concurrency___________        
B)decreased concurrency
C)increased or decreased concurrency
D)concurrency equivalent to other models

Question 23

Which of the following is the drawback of the One to One Model?

A)increased concurrency provided by this model
B)decreased concurrency provided by this model
C)creating so many threads at once can crash the system
D)creating a user thread requires creating the corresponding kernel thread

Question 24

When is the Many to One model at an advantage?

A)when the program does not need multithreading
B)when the program has to be multi- threaded
C)when there is a single processor
D)none of the mentioned

Question 25

In the Many to Many model true concurrency cannot be gained because

A)other threads are strictly prohibited from running
B)other threads are allowed to run
C)other threads only from other processes are allowed to run
D)none of the mentioned