1. What is the main purpose of concurrency control in real-time systems?
(A) To ensure correct and consistent access to shared resources by multiple tasks or transactions
(B) To reduce CPU idle time only
(C) To transfer files in batch mode
(D) To ignore task priorities
2. Which problem does concurrency control primarily address?
(A) Disk fragmentation only
(B) CPU idle exclusively
(C) Race conditions, deadlocks, and inconsistent data updates
(D) Batch file processing
3. Which of the following is a common concurrency control method?
(A) Disk scheduling exclusively
(B) Batch processing only
(C) Lock-based protocols
(D) CPU idle detection
4. In real-time systems, concurrency control must consider:
(A) Only memory optimization
(B) Task priorities and timing constraints
(C) Disk I/O exclusively
(D) Batch file execution
5. What is priority inversion?
(A) Batch task interference
(B) CPU idle time exceeding task deadlines
(C) Disk scheduling conflict
(D) A situation where a high-priority task is blocked by a lower-priority task holding a shared resource
6. Which protocol helps prevent priority inversion in real-time systems?
(A) FIFO disk scheduling exclusively
(B) Round-robin CPU scheduling only
(C) Priority Inheritance Protocol (PIP)
(D) Batch file locking
7. Another method to avoid priority inversion is:
(A) Priority Ceiling Protocol (PCP)
(B) CPU idle monitoring exclusively
(C) Disk-only scheduling
(D) Batch file serialization
8. Lock-based concurrency control can lead to:
(A) Batch processing delays
(B) CPU idle exclusively
(C) Memory leaks only
(D) Deadlocks if multiple tasks wait for each other’s resources
9. Optimistic concurrency control is suitable when:
(A) Only batch processing occurs
(B) Conflicts are constant
(C) Conflicts between tasks are rare
(D) CPU idle is unpredictable
10. In real-time databases, concurrency control must balance:
(A) Memory fragmentation
(B) CPU idle exclusively
(C) Disk batch transfer only
(D) Consistency, isolation, and timeliness of transactions
11. Timestamp ordering is a concurrency control method that:
(A) Serializes batch files
(B) Monitors CPU idle cycles exclusively
(C) Uses disk blocks only
(D) Ensures transactions execute in a timestamp-defined order
12. Two-phase locking (2PL) works by:
(A) CPU idle detection exclusively
(B) Acquiring all locks before releasing any to ensure serializability
(C) Disk scheduling only
(D) Batch file execution
13. Concurrency control in real-time systems differs from conventional systems because:
(A) It must respect task deadlines and timing constraints
(B) CPU idle exclusively
(C) Disk scheduling only
(D) Batch processing
14. Which type of deadlock occurs when two or more tasks are waiting for each other’s resources indefinitely?
(A) Batch processing deadlock
(B) Priority inversion only
(C) CPU idle deadlock exclusively
(D) Circular wait
15. Priority inheritance temporarily:
(A) Disk-only optimization
(B) Reduces CPU usage automatically
(C) Batch process scheduling only
(D) Boosts a lower-priority task holding a resource to the priority of the blocked high-priority task
16. A major goal of concurrency control in real-time systems is:
(A) Reducing memory exclusively
(B) Ensuring predictability and meeting task deadlines
(C) Disk batch optimization only
(D) CPU idle monitoring
17. Which problem does the Priority Ceiling Protocol solve?
(A) CPU idle exclusively
(B) Priority inversion and deadlocks
(C) Disk-only scheduling
(D) Batch file conflicts
18. Deadlock prevention techniques include:
(A) CPU idle detection exclusively
(B) Avoiding circular waits and enforcing resource ordering
(C) Disk-only batch processing
(D) Memory optimization
19. Optimistic methods in concurrency control typically:
(A) Disk-only serialization
(B) Always lock resources indefinitely
(C) CPU idle monitoring exclusively
(D) Execute without locks and validate before committing
20. The main advantage of proper concurrency control in real-time systems is:
(A) Disk optimization only
(B) Batch file execution only
(C) CPU idle monitoring exclusively
(D) Correct, consistent, and predictable execution of multiple tasks sharing resources