Multilevel Feedback Queue Scheduling (MLFQ) CPU Scheduling
Multilevel Feedback Queue Scheduling (MLFQ) CPU Scheduling is like Multilevel Queue(MLQ) Scheduling but in this processes can move between the queues. And thus, much more efficient than multilevel queue scheduling.
Characteristics of Multilevel Feedback Queue Scheduling:
- In a multilevel queue-scheduling algorithm, processes are permanently assigned to a queue on entry to the system and processes are not allowed to move between queues.
- As the processes are permanently assigned to the queue, this setup has the advantage of low scheduling overhead,
- But on the other hand disadvantage of being inflexible.
Advantages of Multilevel Feedback Queue Scheduling:
- It is more flexible.
- It allows different processes to move between different queues.
- It prevents starvation by moving a process that waits too long for the lower priority queue to the higher priority queue.
Disadvantages of Multilevel Feedback Queue Scheduling:
- For the selection of the best scheduler, it requires some other means to select the values.
- It produces more CPU overheads.
- It is the most complex algorithm.