An example of non-preemptive scheduling is

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Kerala PSC Common Preliminary Exam (GRADUATE LEVEL) PYP - 096/21

Answer 1

The correct answer is First Come First Served

Key Points

First Come First Served (FCFS) is the simplest CPU scheduling algorithm.
In FCFS, the process that requests the CPU first is allocated the CPU first.
It is a non-preemptive scheduling algorithm, meaning that once the CPU is allocated to a process, it cannot be taken back until the process completes.
This scheduling method is easy to implement and follows a first-in-first-out (FIFO) queue structure.

Important Points

FCFS is not ideal for systems where processes with shorter execution times are delayed by longer processes.
It may lead to the "convoy effect," where shorter processes have to wait for longer processes to finish.

Additional Information

Round Robin (Option 2): It is a preemptive scheduling algorithm where each process is assigned a fixed time slice (quantum). After the time slice expires, the process is preempted, and the CPU is assigned to the next process in the queue.
Last In First Out (Option 3): It is not a commonly used CPU scheduling algorithm. It implies processing the most recently added process first, which may lead to starvation of older processes.
Shortest Job First (Option 4): It is a scheduling algorithm that selects the process with the smallest execution time next. It can be either preemptive or non-preemptive, depending on the implementation.
Non-Preemptive Scheduling: In non-preemptive scheduling, once a process is given the CPU, it cannot be interrupted until it finishes execution. Examples include First Come First Served (FCFS) and non-preemptive Shortest Job First (SJF).