Question: Can SJF Cause Starvation?

Is Round Robin better than FCFS?

The FCFS is better for a small burst time.

The SJF is better if the process comes to processor simultaneously.

The last algorithm, Round Robin, is better to adjust the average waiting time desired.

Round Robin quantum time will set it towards more SJF or FCFS value..

What is starvation OS?

Starvation is the problem that occurs when high priority processes keep executing and low priority processes get blocked for indefinite time. In heavily loaded computer system, a steady stream of higher-priority processes can prevent a low-priority process from ever getting the CPU.

What are the disadvantages of FCFS scheduling?

Disadvantages: This scheduling method is nonpreemptive, that is, the process will run until it finishes. Because of this nonpreemptive scheduling, short processes which are at the back of the queue have to wait for the long process at the front to finish.

Is starvation possible in FCFS?

In fcfs everyone gets chance to execute based on there arrival. so no starvation in FCFS.

Which scheduling algorithm causes starvation?

As the Shortest remaining time first scheduling is a preemptive version of shortest job scheduling. It may cause starvation as shorter processes may keep coming and a long CPU burst process never gets CPU. … In FIFO how starvation not possible, as if first process takes longer time then last process can cause starvation.

What are the disadvantages of SJF scheduling algorithm?

Here are some drawbacks/cons of SJF algorithm:Job completion time must be known earlier, but it is hard to predict.It is often used in a batch system for long term scheduling.SJF can’t be implemented for CPU scheduling for the short term. … This algorithm may cause very long turnaround times or starvation.More items…•

What is the difference between FCFS and SJF?

First Come First Served (FCFS) executes the processes in the order in which they arrive i.e. the process that arrives first is executed first. Shortest Job First (SJF) executes the processes based upon their burst time i.e. in ascending order of their burst times. FCFS is non preemptive in nature.

Can a system detect starvation?

Q. 7.12 Can a system detect that some of its processes are starving? … Answer: Detection of starvation requires future knowledge since no amount of record-keeping statistics on processes can determine if it is making ‘progress’ or not. However, starvation can be prevented by ‘aging’ a process.

Is starvation possible in round robin?

As the term is generally used, time slices (also known as time quanta) are assigned to each process in equal portions and in circular order, handling all processes without priority (also known as cyclic executive). Round-robin scheduling is simple, easy to implement, and starvation-free.

What are the two steps of a process execution?

As shown in Figure 5.2, a process instance has three main stages during its lifetime: (1) process instantiation, (2) process execution and (3) process termination.

Does FIFO cause starvation?

Yes, pre-emptive scheduling may cause starvation. Let’s see Longest remaining time first scheme. It is pre-emptive scheduling. At any point of time, if any process having larger execution time or larger remaining time arrives, processor will switched to that process pausing current ongoing process.

What is starvation give an example?

An example is maximum throughput scheduling. Starvation is normally caused by deadlock in that it causes a process to freeze. Two or more processes become deadlocked when each of them is doing nothing while waiting for a resource occupied by another program in the same set.