Part 2: W11-1 System Testing Performance

Question 1

What is the objective of system testing?

Answer 1

Verifying the implementation conforms to quality requirements on system level

Question 2

What sort of environment is System Testing performed on?

Answer 2

Emulated environment (similar to production)

Question 3

List 5 common performance problems.

Answer 3

• Poor response time
• Long load time
• Bottlenecking
• Poor scalability
• Disk usage
• Operation system limitations
• Poor network configuration
• Memory utilization
• CPU utilization
• Insufficient hardware resources
• Software configuration issues

Question 4

List 5 common parameters that are monitored.

Answer 4

• Processor usage
• Memory usage
• Disk time
• Bandwidth
• Disk queue length
• Network output queue length
• Response time
• Throughput
• Amount of connection pooling
• Maximum active sessions
• Garbage collection
• Committed memory
• Memory pages/second
• Page faults/second
• CPU interrupts/second
• Network bytes total/second
• Hit ratios
• Hits per second
• Rollback segment
• Database locks
• Top waits
• Thread counts

Question 5

What does processor usage measure?

Answer 5

Time processor spends executing non-idle threads

Question 6

What does disk time measure?

Answer 6

Amount of time disk is reading or writing.

Question 7

What does page faults/second measure?

Answer 7

of times a process requires code outside working set

Question 8

What is a hit ratio?

Answer 8

of SQL statements handled by cache

Question 9

What are the types of performance testing?

Answer 9

1. Load testing
2. Stress testing
3. Scalability testing

Question 10

What is the difference between load testing and stress testing?

Answer 10

Load testing measures operation under full load

Stress testing measure operation under EXTREME load

Question 11

What are the approaches to Performance testing?

Answer 11

1. Benchmarking - measuring absolute performance of application
2. Profiling - measures relative system stats

Question 12

What are ways to implement profiling performance testing?

Answer 12

1. Insertion - placing profiling code in program directly

2. Sampling - monitoring component, saving snapshot of CPU