# What is shortest job first scheduling in operating system?

## What is shortest job first scheduling in operating system?

Shortest job first (SJF) or shortest job next, is a scheduling policy that selects the waiting process with the smallest execution time to execute next. SJN is a non-preemptive algorithm. Shortest Job first has the advantage of having a minimum average waiting time among all scheduling algorithms.

**What is shortest job next SJN algorithm?**

Shortest job next (SJN), also known as shortest job first (SJF) or shortest process next (SPN), is a scheduling policy that selects for execution the waiting process with the smallest execution time. SJN is a non-preemptive algorithm. Shortest remaining time is a preemptive variant of SJN.

**Which data structure is most appropriate for shortest time first CPU scheduler?**

Circular queue is the best data structure for round-robin CPU scheduling algorithm . In round-robin CPU scheduling if the timer goes off first, then the process is swapped out of the CPU and moved to the back end of the ready queue.

### Which scheduling policy has the shortest average waiting time?

SJF is a full form of (Shortest job first) is a scheduling algorithm in which the process with the shortest execution time should be selected for execution next. This scheduling method can be preemptive or non-preemptive. It significantly reduces the average waiting time for other processes awaiting execution.

**Why is the shortest job first optimal?**

SJF is a scheduling algorithm that assigns to each process the length of its next CPU burst/execution time. SJF is provably optimal, in that for a given set of processes and their CPU bursts/execution times it gives the least average waiting time for each process.

**Is shortest job first and shortest job next same?**

Shortest job next (SJN), also known as shortest job first (SJF) or shortest process next (SPN), is a scheduling policy that selects for execution the waiting process with the smallest execution time. SJN is a non-preemptive algorithm.

#### What is shortest job first preemptive?

Shortest Job First – Preemptive Scheduling Algorithm is an algorithm in which the processor is allocated to the job having minimum CPU burst time, but the job can be preempted (Replaced) by a newer job with shorter burst time.

**Which of the following statement is true for shortest job first scheduling?**

Discussion Forum

Que. | 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 terns of response time |
---|---|

b. | i and iii only |

c. | ii and iii only |

d. | i, ii and iii |

Answer:i, ii and iii |

**What is non-preemptive shortest job first?**

Non-preemptive shortest job first The algorithm removes processes with minimum arrival time from the waiting queue and executes them until the process is completed. The process then shifts the CPU to other processes in the waiting queue.

## Which scheduling algorithm gives lesser waiting time?

Shortest Job First (SJF) is an algorithm in which the process having the smallest execution time is chosen for the next execution. This scheduling method can be preemptive or non-preemptive. It significantly reduces the average waiting time for other processes awaiting execution.

**What is first come first serve scheduling?**

First come first serve (FCFS) scheduling algorithm simply schedules the jobs according to their arrival time. The job which comes first in the ready queue will get the CPU first. The lesser the arrival time of the job, the sooner will the job get the CPU.

**What is shortest job first scheduling?**

What is Shortest Job First Scheduling? Shortest Job First (SJF) is an algorithm in which the process having the smallest execution time is chosen for the next execution. This scheduling method can be preemptive or non-preemptive. It significantly reduces the average waiting time for other processes awaiting execution.

### What is shortest job first in Java?

Shortest Job First (SJF) is an algorithm in which the process having the smallest execution time is chosen for the next execution. This scheduling method can be preemptive or non-preemptive.

**What is SJF (shortest job first)?**

Shortest job first (SJF) or shortest job next, is a scheduling policy that selects the waiting process with the smallest execution time to execute next. SJN is a non-preemptive algorithm.

**What is preemptive shortest job first?**

Pre-emptive Shortest Job First. In Preemptive Shortest Job First Scheduling, jobs are put into ready queue as they arrive, but as a process with short burst time arrives, the existing process is preempted or removed from execution, and the shorter job is executed first.