Deck 13: Concurrency Control and Deadlock Prevention in Operating Systems

Question 1

Which is the process of invoking the wait

A)transaction
B)operation
C)function
D)all of the mentioned

Answer 1

transaction

Question 2

Write ahead logging is a way

A)to ensure atomicity
B)to keep data consistent
C)that records data on stable storage
D)all of the mentioned

Answer 2

all of the mentioned

Question 3

The system periodically performs checkpoints that consists of the following operation(s)___________

A)putting all the log records currently in main memory onto stable storage
B)putting all modified data residing in main memory onto stable storage
C)putting a log record onto stable storage
D)all of the mentioned

Answer 3

all of the mentioned

Question 4

A locking protocol is one that

A)governs how locks are acquired
B)governs how locks are released
C)governs how locks are acquired and released
D)none of the mentioned

Question 5

The two phase locking protocol consists of___________

A)growing & shrinking phase
B)shrinking & creation phase
C)creation & growing phase
D)destruction & creation phase

Question 6

The growing phase is a phase in which?

A)a transaction may obtain locks, but does not release any
B)a transaction may obtain locks, and releases a few or all of them
C)a transaction may release locks, but does not obtain any new locks
D)a transaction may release locks, and does obtain new locks

Question 7

What is a reusable resource?

A)that can be used by one process at a time and is not depleted by that use
B)that can be used by more than one process at a time
C)that can be shared between various threads
D)none of the mentioned

Question 8

Which of the following condition is required for a deadlock to be possible?

A)mutual exclusion
B)a process may hold allocated resources while awaiting assignment of other resources
C)no resource can be forcibly removed from a process holding it
D)all of the mentioned

Question 9

Which of the following concurrency control protocols ensure both conflict serializability and freedom from deadlock?

A)the system can allocate resources to each process in some order and still avoid a deadlock
B)there exist a safe sequence
C)all of the mentioned
D)none of the mentioned

Question 10

The circular wait condition can be prevented by___________

A)defining a linear ordering of resource types
B)using thread
C)using pipes
D)all of the mentioned

Question 11

Which one of the following is the deadlock avoidance algorithm?

A)banker's algorithm
B)round-robin algorithm
C)elevator algorithm
D)karn's algorithm

Question 12

What is the drawback of banker's algorithm?

A)in advance processes rarely know how much resource they will need
B)the number of processes changes as time progresses
C)resource once available can disappear
D)all of the mentioned

Question 13

For an effective operating system, when to check for deadlock?

A)every time a resource request is made
B)at fixed time intervals
C)every time a resource request is made at fixed time intervals
D)none of the mentioned

Question 14

A problem encountered in multitasking when a process is perpetually denied necessary resources is called___________

A)deadlock
B)starvation
C)inversion
D)aging

Question 15

Which one of the following is a visual ( mathematical ) way to determine the deadlock occurrence?

A)resource allocation graph
B)starvation graph
C)inversion graph
D)none of the mentioned

Question 16

To avoid deadlock___________

A)there must be a fixed number of resources to allocate
B)resource allocation must be done only once
C)all deadlocked processes must be aborted
D)inversion technique can be used

Question 17

The number of resources requested by a process___________

A)must always be less than the total number of resources available in the system
B)must always be equal to the total number of resources available in the system
C)must not exceed the total number of resources available in the system
D)must exceed the total number of resources available in the system

Question 18

The request and release of resources are

A)command line statements
B)interrupts
C)system calls
D)special programs

Question 19

For a deadlock to arise, which of the following conditions must hold simultaneously?

A)mutual exclusion
B)no preemption
C)hold and wait
D)all of the mentioned

Question 20

For non sharable resources like a printer, mutual exclusion___________

A)must exist
B)must not exist
C)may exist
D)none of the mentioned

Question 21

The disadvantage of a process being allocated all its resources before beginning its execution is___________

A)low cpu utilization
B)low resource utilization
C)very high resource utilization
D)none of the mentioned

Question 22

Each request requires that the system consider the___________  to decide whether the current request can be satisfied or must wait to avoid a future possible deadlock.

A)resources currently available
B)processes that have previously been in the system
C)resources currently allocated to each process
D)future requests and releases of each process

Question 23

A deadlock avoidance algorithm dynamically examines the___________      to ensure that a circular wait condition can never exist.

A)resource allocation state
B)system storage state
C)operating system
D)resources

Question 24

A state is safe, if___________

A)the system does not crash due to deadlock occurrence
B)the system can allocate resources to each process in some order and still avoid a deadlock
C)the state keeps the system protected and safe
D)all of the mentioned

Question 25

A system is in a safe state only if there exists a___________

A)safe allocation
B)safe resource
C)safe sequence
D)all of the mentioned