Bissoy.com
Doctors Medicines MCQs Q&A

Consider the 3 processes, P1, P2 and P3 shown in the table. Process Arrival time Time unit Required P1 0 5 P2 1 7 P3 3 4   The completion order of the 3 processes under the policies FCFS and RR2 (round robin scheduling with CPU quantum of 2 time units) are

Consider the 3 processes, P1, P2 and P3 shown in the table. Process Arrival time Time unit Required P1 0 5 P2 1 7 P3 3 4   The completion order of the 3 processes under the policies FCFS and RR2 (round robin scheduling with CPU quantum of 2 time units) are Correct Answer <strong>FCFS:</strong> P1, P2, P3 <strong>RR2:</strong> P1, P3, P2

The correct answer is "option 3".

CONCEPT:

FCFS is a scheduling algorithm in which the process that scheduled first will execute first completely.

FCFS stands for First Come First Serve.

Round Robin is a scheduling algorithm in which the process executes for a fixed CPU quantum time then the next process gets executed then the next process and goes on.

CALCULATION:

The GANTT chart for the FCFS scheduling algorithm is:

[ alt="F1 Raju S 19.5.21 Pallavi D7" src="//storage.googleapis.com/tb-img/production/21/05/F1_Raju%20S_19.5.21_Pallavi_D7.png" style="width: 283px; height: 55px;">

The completion order for the FCFS scheduling algorithm is: P1 P2 P3

The GANTT chart for the RR scheduling algorithm is:

[ alt="F1 Raju S 19.5.21 Pallavi D8" src="//storage.googleapis.com/tb-img/production/21/05/F1_Raju%20S_19.5.21_Pallavi_D8.png" style="width: 409px; height: 63px;">

The completion order for the RR scheduling algorithm is: P1 P3 P2

Hence, the correct answer is "option 3".

Related Questions

Let processes are scheduled on a system using round robin scheduling; assume that there is only one process of r time units. Round robin time quantum is q time units and process switch time is s time units. If s < q < r, then process switch over head units are
Consider four processes P, Q, R, and S scheduled on a CPU as per round-robin algorithm with a time quantum of 4 units. The processes arrive in the order P, Q, R, S, all at time t = 0. There is exactly one context switch from S to Q, exactly one context switch from R to Q, and exactly two context switches from Q to R. There is no context switch from S to P. Switching to a ready process after the termination of another process is also considered a context switch. Which one of the following is NOT possible as CPU burst time (in time units) of these processes?  
An operating system uses the Banker’s algorithm for deadlock avoidance when managing the allocation of three resource types X, Y, and Z to three processes P0, P1, and P2. The table given below presents the current system state. Here, the Allocation matrix shows the current number of resources of each type allocated to each process and the Max matrix shows the maximum number of resources of each type required by each process during its execution.   Allocation Max   X Y Z X Y Z P0 0 0 1 8 4 3 P1 3 2 0 6 2 0 P2 2 1 1 3 3 3   There are 3 units of type X, 2 units of type Y and 2 units of type Z still available. The system is currently in a safe state. Consider the following independent requests for additional resources in the current state: REQ1: P0 requests 0 units of X, 0 units of Y and 2 units of Z REQ2: P1 requests 2 units of X, 0 units of Y and 0 units of Z Which one of the following is TRUE?
Which of the following statements are true? I. Shortest remaining time first scheduling may cause starvation II. Preemptive scheduling may cause starvation III. Round robin is better than FCFS in terms of response time
Raw material purchased:
1st January, 600 units @ Rs. 12 per unit
12th January, 500 units @ Rs. 14 per unit
21st January, 300 units @ Rs. 13 per unit
Raw material issued for manufacture:
3rd January 300 units
5th January 124 units
15th January 250 units
16th January 300 units
Raw material returned to stores from manufacturing department on 14th January, 50 units. The material is issued on First-in-First out method.
The value of material remaining in store on 21st January will be:
The rate of electricity in the rural area is given below: i) up to 25 units - Rs 5 per unit ii) up to 75 units - Rs 7 per units iii) up to 100 units - Rs 9 per units iv) After 100 units - Rs 13 per units Additional charge after 100 units = Rs. 50 The consumption of the electricity of the household is 120 units. How much electricity bill he has to pay?
One of the Scheduling method is also known as Shortest-­next­-CPU­-burst algorithm, because scheduling through this method depends on the length of the next CPU burst of a process rather than its total length. Which of the following scheduling method is being discussed here?
A product 'A' comprises of 2 units of B and 3 units of C. Each unit of B requires 2 unit of D and one unit of E. Each unit of C needs 2 units of E and one unit of F. How many number of end units of E are required for producing 2 units of A ?
Suppose a system contains n processes and system uses the round-robin algorithm for CPU scheduling then which data structure is best suited ready queue of the processes  
There are 10 different processes running on a workstation. Idle processes are waiting for an input event in the input queue. Busy processes are scheduled with the Round-Robin time sharing method. Which out of the following quantum times is the best value for small response times, if the processes have a short runtime, e.g. less than 10ms?