GATE CSE 2020 | Question: 12

Question

Consider the following statements about process state transitions for a system using preemptive scheduling.

1. A running process can move to ready state.
2. A ready process can move to running state.
3. A blocked process can move to running state.
4. A blocked process can move to ready state.

Which of the above statements are TRUE?

• A. I, II, and III only
• B. II and III only
• C. I, II, and  IV only
• D. I, II, III and IV  only

Comments

Same question without any change in word or options was asked in BARC 2020.

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Similar question: https://gateoverflow.in/1318/gate2009-32

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Add process-scheduling tag.

Answer 1

A blocked process cannot go to running state directly. Except (III), every option is viable.

Answer-(C)

Comments

@Shubham The question didn't mention "directly". It just says "can" it move or not

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Caption

but iitgatedelhi in there key  has given it answer as B option

2 and 3 option ,i have choosen option c

 

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@Warlord No, iit gate delhi has same answer as here (and same as you have marked), Check again.

Answer 2

As we can see a blocked process cannot be move to running state. It can either go to suspend wait or ready state from blocked state. Hence $III.$ is false.

$\therefore$ Option $C.$ is correct answer

Answer 3

Whenever the blocked process has to run again...first it has to move to ready state then to run state.

Therefore only (III) is wrong

Ans: (C)  I,II,IV are correct

Answer 4

All processes, upon entering into the system, are stored in the Job Queue.

Processes in the Ready state are placed in the Ready Queue.

Processes waiting for a device to become available are placed in Device Queues. There are unique device queues available for each I/O device.

A new process is initially put in the Ready queue. It waits in the ready queue until it is selected for execution(or dispatched). Once the process is assigned to the CPU and is executing, one of the following several events can occur:

The process could issue an I/O request, and then be placed in the I/O queue.

The process could create a new subprocess and wait for its termination.

The process could be removed forcibly from the CPU, as a result of an interrupt, and be put back in the ready queue..