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Which type of process spends more time doing I/O than computations and has many short CPU bursts?
Which type of process spends more time doing I/O than computations and has many short CPU bursts?
What is the main concern when it comes to CPU burst distribution?
What is the main concern when it comes to CPU burst distribution?
Which scheduler selects which process should be executed next and allocated the CPU?
Which scheduler selects which process should be executed next and allocated the CPU?
Which scheduler selects which processes should be brought into the ready queue?
Which scheduler selects which processes should be brought into the ready queue?
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Which scheduler controls the degree of multiprogramming?
Which scheduler controls the degree of multiprogramming?
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Which type of process spends more time doing computations and has few very long CPU bursts?
Which type of process spends more time doing computations and has few very long CPU bursts?
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Which scheduler is invoked frequently and must be fast?
Which scheduler is invoked frequently and must be fast?
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Which scheduler is invoked infrequently and may be slow?
Which scheduler is invoked infrequently and may be slow?
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What is the objective of the long-term scheduler?
What is the objective of the long-term scheduler?
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What is the objective of the short-term scheduler?
What is the objective of the short-term scheduler?
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Which scheduling algorithm is considered fair but has a poor average waiting time?
Which scheduling algorithm is considered fair but has a poor average waiting time?
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Which scheduling algorithm is not fair and has a poor average waiting time?
Which scheduling algorithm is not fair and has a poor average waiting time?
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Which scheduling algorithm minimizes the average waiting time assuming accurate prediction of the next CPU burst length, but can lead to starvation?
Which scheduling algorithm minimizes the average waiting time assuming accurate prediction of the next CPU burst length, but can lead to starvation?
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Which scheduling algorithm is an approximation of SJF and uses multiple queues?
Which scheduling algorithm is an approximation of SJF and uses multiple queues?
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In SJF scheduling, what is the average waiting time for the following burst times: P1: 3, P2: 16, P3: 9, P4: 0?
In SJF scheduling, what is the average waiting time for the following burst times: P1: 3, P2: 16, P3: 9, P4: 0?
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In preemptive SJF scheduling with varying arrival times, what is the average waiting time for the following burst times and arrival times: P1: 1 (arrival: 0), P2: 5 (arrival: 1), P3: 2 (arrival: 2), P4: 4 (arrival: 3)?
In preemptive SJF scheduling with varying arrival times, what is the average waiting time for the following burst times and arrival times: P1: 1 (arrival: 0), P2: 5 (arrival: 1), P3: 2 (arrival: 2), P4: 4 (arrival: 3)?
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In priority scheduling, which process will be executed first if the priority numbers are as follows: P1: 3, P2: 1, P3: 4, P4: 5, P5: 2?
In priority scheduling, which process will be executed first if the priority numbers are as follows: P1: 3, P2: 1, P3: 4, P4: 5, P5: 2?
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In round robin scheduling with a time quantum of 4, what is the average waiting time for the following burst times: P1: 24, P2: 3, P3: 3?
In round robin scheduling with a time quantum of 4, what is the average waiting time for the following burst times: P1: 24, P2: 3, P3: 3?
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In round robin scheduling, if there are 4 processes and the time quantum is 5, how many time units will each process get at most?
In round robin scheduling, if there are 4 processes and the time quantum is 5, how many time units will each process get at most?
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In round robin scheduling, what is the maximum waiting time for a process if there are 5 processes and the time quantum is 10?
In round robin scheduling, what is the maximum waiting time for a process if there are 5 processes and the time quantum is 10?
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Which process scheduling algorithm aims to keep the CPU as busy as possible?
Which process scheduling algorithm aims to keep the CPU as busy as possible?
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What is the waiting time for process P2 in the FCFS scheduling algorithm if the process burst times are P1=24, P2=3, P3=3 and the processes arrive in the order P1, P2, P3?
What is the waiting time for process P2 in the FCFS scheduling algorithm if the process burst times are P1=24, P2=3, P3=3 and the processes arrive in the order P1, P2, P3?
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Which scheduling algorithm is optimal and gives the minimum average waiting time for a given set of processes?
Which scheduling algorithm is optimal and gives the minimum average waiting time for a given set of processes?
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What is the context-switch time in an operating system?
What is the context-switch time in an operating system?
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Which scheduling decision is nonpreemptive?
Which scheduling decision is nonpreemptive?
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What is the formula for calculating waiting time in nonpreemptive scheduling algorithms?
What is the formula for calculating waiting time in nonpreemptive scheduling algorithms?
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What is the formula for calculating turnaround time in preemptive scheduling algorithms?
What is the formula for calculating turnaround time in preemptive scheduling algorithms?
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What is the goal of CPU scheduling?
What is the goal of CPU scheduling?
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What is the average waiting time for the FCFS scheduling algorithm if the processes arrive in the order P2, P3, P1 and the process burst times are P1=24, P2=3, P3=3?
What is the average waiting time for the FCFS scheduling algorithm if the processes arrive in the order P2, P3, P1 and the process burst times are P1=24, P2=3, P3=3?
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Which scheduling algorithm may result in the convoy effect?
Which scheduling algorithm may result in the convoy effect?
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Which type of process spends more time doing computations and has few very long CPU bursts?
Which type of process spends more time doing computations and has few very long CPU bursts?
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Which scheduler is invoked frequently and must be fast?
Which scheduler is invoked frequently and must be fast?
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What is the formula for calculating turnaround time in preemptive scheduling algorithms?
What is the formula for calculating turnaround time in preemptive scheduling algorithms?
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Which process scheduling algorithm aims to keep the CPU as busy as possible?
Which process scheduling algorithm aims to keep the CPU as busy as possible?
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What is the formula for calculating waiting time in nonpreemptive scheduling algorithms?
What is the formula for calculating waiting time in nonpreemptive scheduling algorithms?
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Which scheduling algorithm minimizes the average waiting time assuming accurate prediction of the next CPU burst length, but can lead to starvation?
Which scheduling algorithm minimizes the average waiting time assuming accurate prediction of the next CPU burst length, but can lead to starvation?
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Which scheduler controls the degree of multiprogramming?
Which scheduler controls the degree of multiprogramming?
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Which scheduling algorithm is considered fair but has a poor average waiting time?
Which scheduling algorithm is considered fair but has a poor average waiting time?
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What is the average waiting time for the FCFS scheduling algorithm if the processes arrive in the order P2, P3, P1 and the process burst times are P1=24, P2=3, P3=3?
What is the average waiting time for the FCFS scheduling algorithm if the processes arrive in the order P2, P3, P1 and the process burst times are P1=24, P2=3, P3=3?
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What is the average waiting time for the following burst times in SJF scheduling: P1: 3, P2: 16, P3: 9, P4: 0?
What is the average waiting time for the following burst times in SJF scheduling: P1: 3, P2: 16, P3: 9, P4: 0?
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In round robin scheduling with a time quantum of 4, what is the average waiting time for the following burst times: P1: 24, P2: 3, P3: 3?
In round robin scheduling with a time quantum of 4, what is the average waiting time for the following burst times: P1: 24, P2: 3, P3: 3?
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Study Notes
Process Scheduling
- I/O-bound processes spend more time doing I/O than computations and have many short CPU bursts.
- CPU-bound processes spend more time doing computations and have few very long CPU bursts.
Schedulers
- Short-term scheduler selects which process should be executed next and allocated the CPU.
- Long-term scheduler selects which processes should be brought into the ready queue.
- Medium-term scheduler controls the degree of multiprogramming.
Scheduling Algorithms
- Short-term scheduler is invoked frequently and must be fast.
- Long-term scheduler is invoked infrequently and may be slow.
- The objective of the long-term scheduler is to control the degree of multiprogramming.
- The objective of the short-term scheduler is to select which process should be executed next.
Scheduling Algorithms' Properties
- First Come First Served (FCFS) is not optimal and can result in convoy effect.
- Shortest Job First (SJF) minimizes the average waiting time assuming accurate prediction of the next CPU burst length, but can lead to starvation.
- Priority scheduling is not fair and has a poor average waiting time.
- Round Robin (RR) is an approximation of SJF and uses multiple queues.
- Multilevel Feedback Queue (MFQ) aims to keep the CPU as busy as possible.
Calculating Waiting Time and Turnaround Time
- The formula for calculating waiting time in nonpreemptive scheduling algorithms is: Waiting Time = Burst Time of Previous Process.
- The formula for calculating turnaround time in preemptive scheduling algorithms is: Turnaround Time = Burst Time + Waiting Time.
Scheduling Goals
- The goal of CPU scheduling is to minimize the average waiting time.
Specific Scheduling Scenarios
- In SJF scheduling, the average waiting time for burst times P1: 3, P2: 16, P3: 9, P4: 0 is 11.
- In preemptive SJF scheduling with varying arrival times, the average waiting time for burst times P1: 1 (arrival: 0), P2: 5 (arrival: 1), P3: 2 (arrival: 2), P4: 4 (arrival: 3) is 4.
- In priority scheduling, the process with the highest priority number will be executed first.
- In round robin scheduling with a time quantum of 4, the average waiting time for burst times P1: 24, P2: 3, P3: 3 is 10.
- In round robin scheduling, if there are 4 processes and the time quantum is 5, each process will get at most 5 time units.
- In round robin scheduling, the maximum waiting time for a process if there are 5 processes and the time quantum is 10 is 40.
- The waiting time for process P2 in the FCFS scheduling algorithm if the process burst times are P1=24, P2=3, P3=3 and the processes arrive in the order P1, P2, P3 is 27.
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Description
Test your knowledge on CPU scheduling algorithms and evaluation criteria in operating systems. This quiz covers important concepts from Chapter 5 of the book "Operating System Concepts – 10th Edition" by Silberschatz, Galvin, and Gagne.
