RTES - 3 - Quiz 1

1. A Flight Control System is a Real Time System

• True
• False

2. Real-Time correctness requires what?

• Resource margins greater than 30%
• Periodic processing of service requests with no jitter and no drift
• Servicing requests as fast and efficiently as possible
• High throughput, bandwidth and a small memory footprint
• Functionally correct output prior to a deadline relative to request for all services

3. All embedded systes are real-time systems

• False
• True

4. Interference time is best described as what?

• Time during which a thread/task is preempted by another with higher priority
• An inversion in priority
• When a thread/task is dispatched but has insufficient memory
• Level-1 cache misses the reduce execution efficiency
• Stalls in the microprocessor pipeline during execution

5. Which of the following are attributes of a Linux process?

• A process provides a protected address space, which can’t be corrupted by bad code running in a separate process
• A process is a kenel space execution context mapped onto a user space task
• A process is a user space excution context and it is mapped onto a task in kernel space in Linux
• The Linux kernel is just a process
• The Linux process is the best way to implement a real-time service.

Answers

1. True
2. Functionally correct output prior to a deadline relative to request for all services
3. False
4. Time during which a thread/task is preempted by another with higher priority
5. A process provides a protected address space, which can’t be corrupted by bad code running in a separate process
   A process is a user space excution context and it is mapped onto a task in kernel space in Linux