GATE CSE 2020 Q22: Valid process state transitions under preemptive scheduling
- Operating System
- 1 mark
- MCQ
- −1/3 if wrong
Question
Consider the following statements about process state transitions for a system using preemptive scheduling.
I. A running process can move to ready state.
II. A ready process can move to running state.
III. A blocked process can move to running state.
IV. A blocked process can move to ready state.
Which of the above statements are TRUE?
Try it: multiple choice: exactly one correct option
Show answer and explanation
Answer: C (official GATE 2020 final answer key)
Concept used: Process state diagram: a blocked process must become ready before it can be dispatched.
First step: Preemption gives running → ready; dispatch gives ready → running; I/O completion moves blocked to ready, never straight to running.
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Source: official GATE 2020 CS question paper and final answer key, organised by IIT Delhi. Question paper · Answer key
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