130+ Embedded Real Time Operating System Solved MCQs

101.

Preemptive, priority based scheduling guarantees ____________

A. hard real time functionality
B. soft real time functionality
C. protection of memory
D. none of the mentioned
Answer» B. soft real time functionality
102.

What is Event latency?

A. the amount of time an event takes to occur from when the system started
B. the amount of time from the event occurrence till the system stops
C. the amount of time from event occurrence till the event crashes
D. the amount of time that elapses from when an event occurs to when it is serviced.
Answer» D. the amount of time that elapses from when an event occurs to when it is serviced.
103.

Real time systems need to __________ the interrupt latency.

A. minimize
B. maximize
C. not bother about
D. none of the mentioned
Answer» A. minimize
104.

The amount of time required for the scheduling dispatcher to stop one process and start another is known as ______________

A. event latency
B. interrupt latency
C. dispatch latency
D. context switch
Answer» C. dispatch latency
105.

The most effective technique to keep dispatch latency low is to ____________

A. provide non preemptive kernels
B. provide preemptive kernels
C. make it user programmed
D. run less number of processes at a time
Answer» B. provide preemptive kernels
106.

Antilock brake systems, flight management systems, pacemakers are examples of

A. safety critical system
B. hard real time system
C. soft real time system
D. safety critical system and hard real time system
Answer» D. safety critical system and hard real time system
107.

In real time operating system ____________

A. all processes have the same priority
B. a task must be serviced by its deadline period
C. process scheduling can be done only once
D. kernel is not required
Answer» B. a task must be serviced by its deadline period
108.

In a real time system the computer results ____________

A. must be produced within a specific deadline period
B. may be produced at any time
C. may be correct
D. all of the mentioned
Answer» A. must be produced within a specific deadline period
109.

. If there are a total of T = 100 shares to be divided among three processes, A, B and C. A is assigned 50 shares, B is assigned 15 shares and C is assigned 20 shares.B will have ______ percent of the total processor time.

A. 20
B. 15
C. 50
D. none of the mentioned
Answer» B. 15
110.

Earliest deadline first algorithm assigns priorities according to ____________

A. periods
B. deadlines
C. burst times
D. none of the mentioned
Answer» B. deadlines
111.

A process P1 has a period of 50 and a CPU burst of t1 = 25, P2 has a period of 80 and a CPU burst of 35. The total CPU utilization is ____________

A. 0.90
B. 0.74
C. 0.94
D. 0.80
Answer» C. 0.94
112.

A process P1 has a period of 50 and a CPU burst of t1 = 25, P2 has a period of 80 and a CPU burst of 35., the priorities of P1 and P2 are?

A. remain the same throughout
B. keep varying from time to time
C. may or may not be change
D. none of the mentioned
Answer» B. keep varying from time to time
113.

A process P1 has a period of 50 and a CPU burst of t1 = 25, P2 has a period of 80 and a CPU burst of 35., can the two processes be scheduled using the EDF algorithm without missing their respective deadlines?

A. Yes
B. No
C. Maybe
D. None of the mentioned
Answer» A. Yes
114.

Using EDF algorithm practically, it is impossible to achieve 100 percent utilization due to __________

A. the cost of context switching
B. interrupt handling
C. power consumption
D. all of the mentioned
Answer» A. the cost of context switching
115.

If there are a total of T = 100 shares to be divided among three processes, A, B and C. A is assigned 50 shares, B is assigned 15 shares and C is assigned 20 shares.A will have ______ percent of the total processor time.

A. 20
B. 15
C. 50
D. none of the mentioned
Answer» C. 50
116.

If there are a total of T = 100 shares to be divided among three processes, A, B and C. A is assigned 50 shares, B is assigned 15 shares and C is assigned 20 shares.C will have ______ percent of the total processor time.

A. 20
B. 15
C. 50
D. none of the mentioned
Answer» A. 20
117.

If there are a total of T = 100 shares to be divided among three processes, A, B and C. A is assigned 50 shares, B is assigned 15 shares and C is assigned 20 shares.If a new process D requested 30 shares, the admission controller would __________

A. allocate 30 shares to it
B. deny entry to D in the system
C. all of the mentioned
D. none of the mentioned
Answer» B. deny entry to D in the system
118.

In a safety critical system, incorrect operation ____________

A. does not affect much
B. causes minor problems
C. causes major and serious problems
D. none of the mentioned
Answer» C. causes major and serious problems
119.

The amount of memory in a real time system is generally ____________

A. less compared to PCs
B. high compared to PCs
C. same as in PCs
D. they do not have any memory
Answer» A. less compared to PCs
120.

What is the priority of a real time task?

A. must degrade over time
B. must not degrade over time
C. may degrade over time
D. none of the mentioned
Answer» B. must not degrade over time
121.

Memory management units ____________

A. increase the cost of the system
B. increase the power consumption of the system
C. increase the time required to complete an operation
D. all of the mentioned
Answer» D. all of the mentioned
122.

A process P1 has a period of 50 and a CPU burst of t1 = 25, P2 has a period of 80 and a CPU burst of 35. Can the processes be scheduled without missing the deadlines?

A. Yes
B. No
C. Maybe
D. None of the mentioned
Answer» B. No
123.

Type of processor in which single task of a particular application is process is termed as Select one:

A. real time processor
B. dedicated processor
C. applicant processor
D. one task processor
Answer» B. dedicated processor
124.

Calculate the idle time of the processor with 3 periodic tasks whose execution times are given as 1, 1, and 3, and their periods are 3, 4, and 10. Select one: 17% 12% 88%

A. 0.17
B. 0.12
C. 0.88
D. 1
Answer» B. 0.12
125.

In rate monotonic scheduling algorithm Select one:

A. shorter duration job has higher priority,
B. longer duration job has higher priority
C. priority does not depend on the duration of the job
D. none of the mentioned
Answer» B. longer duration job has higher priority
126.

Tasks whose execution would begin randomly and within the interval of arrival times of consecutive tasks is known as

A. Periodic Task
B. Aperiodic Task
C. Sporadic Task
D. none of the mentioned
Answer» C. Sporadic Task
127.

What is True for a task vis-à-vis a process?

A. Tasks are complex compared to processes
B. Tasks represent only a single sequence of instructions
C. Processes can spawn threads but tasks cannot spawn tasks Tasks and processes are one and the same thing
D. Tasks and processes are one and the same thing
Answer» B. Tasks represent only a single sequence of instructions
128.

What does the utilization rate tells us? Select one:

A. If it is larger or equal to 1, the system is not feasible
B. If it is smaller than 1, the system is feasible
C. If it is exactly 1, the system is feasible
D. if there is no context switch overhead If it is 0, the system is absolutely feasible
Answer» A. If it is larger or equal to 1, the system is not feasible
129.

if jobs have unpredictable release times, a task is termed :

A. aperiodic
B. sporadic periodic.
C. both
D. None of these
Answer» A. aperiodic
130.

What is TRUE for an aperiodic task and a sporadic task:

A. A sporadic task and an aperiodic task are one and the same thing
B. An aperiodic task occurs randomly and has hard real time requirements
C. A sporadic task occurs randomly and has hard real time requirements
D. A sporadic task becomes aperiodic when it is executed with a periodic task
Answer» C. A sporadic task occurs randomly and has hard real time requirements
131.

State whether the following statements are True or False for the features of real time operating system.
i) fast process or thread switch
ii) ability to respond to external interrupts quickly.
iii) minimization of intervals during which interrupts are enabled.
iv) preemptive scheduling based on priority

A. i, ii and iii only
B. ii, iii and iv only
C. i, ii and iv only
D. All i, ii, iii and iv
Answer» C. i, ii and iv only
132.

Effective release time of a job without the predecessors is equal to its given …………….

A. release time
B. Deadline
C. both
D. None of these
Answer» A. release time
133.

Effective release time of a job with predecessors is equal to the maximum value among, its…………and…………..

A. deadline time and effective release time of all of the predecessors.
B. release time and effective release time of all of the predecessors.
C. both
D. None of these
Answer» B. release time and effective release time of all of the predecessors.
134.

Effective deadline of job without the successor is equal to its given ……………

A. release time
B. Deadline
C. both
D. None of these
Answer» B. Deadline
135.

Effective deadline of job with successor is equal tothe minimum value among its deadlines and …………………………

A. only deadline of job
B. Release time of all the successors
C. deadlines of all the successors
D. None of these
Answer» C. deadlines of all the successors
136.

LRT schedules all the job backward from …………………... of all the job in priority driven manner to the current time.

A. Earliest deadline
B. latest deadline
C. latest releasetime
D. None of these
Answer» B. latest deadline
137.

In on-line scheduling, scheduler make the schedule ……………………... that will be released in future.

A. with the knowledge of the jobs
B. without the knowledge of the jobs
C. both
D. None of these
Answer» B. without the knowledge of the jobs
138.

In which scheduling certain amount of CPU time is allocated to each process ?

A. earliest deadline first scheduling
B. roportional share scheduling
C. equal share scheduling
D. none of the mentioned
Answer» B. roportional share scheduling
139.

Scheduling of tasks is a very important consideration in RTOS. Which of the following best described the scheduling policy design:

A. The scheduler must follow a pre-emptive policy
B. The scheduler must not use pre-emptive policy option
C. The scheduler must not only use pre-emptive policy options with the priority considerations.
D. The scheduler must not use pre-emptive policy option, but must employ priority consideration.
Answer» D. The scheduler must not use pre-emptive policy option, but must employ priority consideration.
Tags
Question and answers in Embedded Real Time Operating System, Embedded Real Time Operating System multiple choice questions and answers, Embedded Real Time Operating System Important MCQs, Solved MCQs for Embedded Real Time Operating System, Embedded Real Time Operating System MCQs with answers PDF download