Question

Explain the differences in the degree to which the following scheduling

algorithms discriminate in favor of short processes:
a. FCFS
b. RR
c. Multilevel feedback queues

Answer 1

FCFS, RR, and Multilevel Feedback Queues scheduling algorithms differ in their discrimination towards short processes.

Step-by-step explanation:

FCFS (First-Come, First-Served) Scheduling Algorithm:

This algorithm does not discriminate in favor of short processes. It works on the principle of serving the processes in the order they arrive. If a long process arrives first, it will be executed before any shorter processes.

RR (Round Robin) Scheduling Algorithm:

This algorithm also does not discriminate in favor of short processes. It allocates a fixed time quantum to each process and switches between processes in a circular manner. Each process is given an equal opportunity to execute, regardless of its length.

Multilevel Feedback Queues Scheduling Algorithm:

This algorithm discriminates in favor of short processes. It assigns different priority levels to processes based on their characteristics. Short processes are assigned higher priority, allowing them to be executed sooner. Longer processes may be delayed as they are assigned lower priority levels.

Answer 2

The degree to which scheduling algorithms discriminate in favor of short processes varies:

The Differences

a. FCFS (First-Come, First-Served): FCFS doesn't prioritize shorter processes. It schedules tasks based on their arrival time, favoring the first process in the queue.

b. RR (Round Robin): RR treats all processes equally, offering each process an equal time slice for execution. While it doesn't inherently favor short processes, it ensures fair access to CPU time by providing smaller time slices, allowing shorter processes to complete within their allotted time.

c. Multilevel feedback queues: This algorithm discriminates in favor of short processes by dynamically prioritizing shorter jobs. It uses multiple queues, allowing shorter processes to move to higher-priority queues for faster execution, ensuring responsiveness for short tasks.