Question

Which data structure is used to implement priority scheduling?

• A. Stack
• B. Queue
• C. Priority queue
• D. Linked list

Hint:

Priority Queues are most commonly implemented using a Heap data structure (Binary Heap), which allows for efficient $O(\log n)$ insertion and deletion of the maximum/minimum element.

Answer 1

The Correct Option is C

Concept: Scheduling involves determining the order in which tasks or processes are executed.
• Standard Scheduling: Usually follows a First-Come-First-Served (FCFS) logic.
• Priority Scheduling: Tasks are assigned a priority value and are executed based on that value.

Step 1: Comparing Queue and Priority Queue.
A regular Queue serves elements purely based on their arrival time. A Priority Queue serves elements based on their associated importance.

Step 2: Defining Priority Queue behavior.
In this structure, the element with the highest priority is dequeued first. If two elements have the same priority, they are served according to their order in the queue.

Step 3: Identifying implementation in OS.
Operating systems use this for process management. High-priority tasks (like system interrupts) must be handled before low-priority tasks.