Multilevel queue scheduling in Operating Systems - Practice Problems & Coding Challenges

Challenge - 5 Problems

🧠 Conceptual

intermediate

Understanding the basic structure of multilevel queue scheduling

In multilevel queue scheduling, processes are divided into separate queues. Which statement best describes how these queues are managed?

A All queues share the same scheduling algorithm and processes can move freely between them.

B Each queue has its own scheduling algorithm, and processes do not move between queues.

C Processes are assigned to queues dynamically based on their CPU burst time during execution.

D There is only one queue, but it is divided into segments that change priority dynamically.

💡 Hint

Think about whether processes can switch queues once assigned.

In multilevel queue scheduling, each queue is assigned a fixed scheduling algorithm, and processes are permanently assigned to one queue based on their characteristics. They do not move between queues.

📋 Factual

intermediate

Priority handling in multilevel queue scheduling

Which of the following best describes how priority is handled in multilevel queue scheduling?

A Priority is assigned dynamically to each process regardless of its queue.

B Priority is ignored; processes are scheduled based on arrival time only.

C Queues are assigned fixed priorities, and higher priority queues are scheduled before lower priority ones.

D All queues have equal priority and are scheduled in a round-robin fashion.

💡 Hint

Consider how the system decides which queue to serve first.

In multilevel queue scheduling, each queue has a fixed priority level. The scheduler always selects processes from the highest priority queue first before moving to lower priority queues.

🔍 Analysis

advanced

Effect of starvation in multilevel queue scheduling

Consider a multilevel queue scheduling system where the highest priority queue is always busy. What is the most likely effect on processes in lower priority queues?

A Processes in lower priority queues will eventually get CPU time as the scheduler cycles through all queues equally.

B Lower priority queues will preempt higher priority queues to prevent starvation.

C Processes in lower priority queues will be promoted to higher priority queues automatically.

D Processes in lower priority queues may suffer starvation and wait indefinitely for CPU time.

💡 Hint

Think about what happens if the highest priority queue never becomes empty.

If the highest priority queue is always busy, lower priority queues may never get CPU time, causing starvation where their processes wait indefinitely.

❓ Comparison

advanced

Difference between multilevel queue and multilevel feedback queue scheduling

Which statement correctly distinguishes multilevel queue scheduling from multilevel feedback queue scheduling?

A Multilevel feedback queue scheduling allows processes to move between queues based on their behavior; multilevel queue scheduling assigns processes permanently to one queue.

B Multilevel queue scheduling uses dynamic priorities; multilevel feedback queue scheduling uses fixed priorities.

C Both scheduling types assign processes permanently to one queue without movement.

D Multilevel queue scheduling allows processes to move between queues; multilevel feedback queue scheduling does not.

💡 Hint

Focus on whether processes can change queues during execution.

Multilevel feedback queue scheduling allows processes to move between queues based on their CPU usage and behavior, while multilevel queue scheduling assigns processes permanently to a fixed queue.

❓ Reasoning

expert

Choosing scheduling algorithms for queues in multilevel queue scheduling

In a multilevel queue scheduling system with three queues: system processes, interactive processes, and batch processes, which combination of scheduling algorithms is most appropriate to optimize responsiveness and throughput?

A System processes: Priority Scheduling; Interactive processes: Round Robin; Batch processes: First-Come, First-Served

B System processes: Round Robin; Interactive processes: First-Come, First-Served; Batch processes: Priority Scheduling

C System processes: First-Come, First-Served; Interactive processes: Priority Scheduling; Batch processes: Round Robin

D System processes: Round Robin; Interactive processes: Priority Scheduling; Batch processes: Round Robin

💡 Hint

Consider which processes need quick response and which can tolerate delays.

System processes often require high priority and quick handling, so Priority Scheduling fits best. Interactive processes benefit from Round Robin to ensure responsiveness. Batch processes can use First-Come, First-Served as they are less time-sensitive.