Performance monitoring and optimization in SCADA systems - Practice Problems & Coding Challenges

Challenge - 5 Problems

💻 Command Output

intermediate

Interpreting CPU Usage Command Output

You run the command top -b -n1 on a SCADA system to check CPU usage. Which line correctly shows the CPU idle percentage?

SCADA systems

top -b -n1
Cpu(s):  5.0%us,  3.0%sy,  0.0%ni, 90.0%id,  1.0%wa,  0.0%hi,  1.0%si,  0.0%st

A 90.0%id means CPU is 90% idle

B 5.0%us means CPU is 90% idle

C 3.0%sy means CPU is 3% idle

D 1.0%wa means CPU is 1% idle

💡 Hint

Look for the 'id' label which stands for idle time.

In the output, 'id' stands for idle CPU percentage. Here it is 90.0%, meaning CPU is mostly idle.

🧠 Conceptual

intermediate

Choosing the Right Metric for Network Latency

Which metric is best to monitor network latency in a SCADA system to detect delays in sensor data transmission?

A Round-trip time (RTT)

B Disk I/O wait time

C Packet loss percentage

D CPU usage percentage

💡 Hint

Latency measures the time it takes for data to travel back and forth.

Round-trip time (RTT) measures the time for a packet to go to a destination and back, which reflects network latency.

❓ Troubleshoot

advanced

Diagnosing High Memory Usage in SCADA

A SCADA system shows high memory usage causing slow response. Which command output indicates a memory leak?

SCADA systems

free -m
              total        used        free      shared  buff/cache   available
Mem:           2048        1900          50          10         98          30

A High 'shared' memory with high 'free' memory

B High 'buff/cache' memory with low 'used' memory

C High 'used' memory with very low 'free' and 'available' memory

D Low 'used' memory with high 'available' memory

💡 Hint

Memory leaks cause used memory to grow and free memory to shrink.

When 'used' memory is very high and 'free' and 'available' memory are very low, it suggests a memory leak or excessive memory consumption.

🔀 Workflow

advanced

Optimizing SCADA System Performance Workflow

What is the correct order of steps to optimize SCADA system performance after detecting high CPU usage?

A 2,1,3,4

B 1,2,3,4

C 1,3,2,4

D 3,1,2,4

💡 Hint

Start by finding the cause, then analyze, fix, and monitor.

First identify the CPU-heavy processes, then analyze if usage is expected, apply fixes, and finally monitor results.

✅ Best Practice

expert

Best Practice for Continuous Performance Monitoring

Which approach is best for continuous performance monitoring and alerting in a SCADA system?

A Manually run performance commands daily and check logs

B Rely on user reports to detect performance issues

C Restart the SCADA system weekly to prevent issues

D Use automated monitoring tools with threshold-based alerts and dashboards

💡 Hint

Automation helps catch issues early and reduces manual work.

Automated tools with alerts and dashboards provide real-time monitoring and quick response to performance problems.