"Performance measurements with Java Microbenchmark Harness (JMH)" at Eclipse Demo Camp 2017 by Vadym Kazulkin

1. by Vadym Kazulkin, ip.labs GmbH
Performance measurements
with Java Microbenchmarking Harness (JMH) Framework in your IDE

2. Contact
Vadym Kazulkin, ip.labs GmbH:
Email : v.kazulkin@iplabs.de
Xing : https://www.xing.com/profile/Vadym_Kazulkin
Twitter: @VKazulkin

3. Java Microbenchmarking Harness (JMH) Framework by Vadym Kazulkin, ip.labs GmbH
ip.labs GmbH

4. Java Microbenchmarking Harness (JMH) Framework by Vadym Kazulkin, ip.labs GmbH
Purpose of benchmarking
• Compare different implementations of code the same logic and choose the most
performant one.
• Identify bottlenecks in a suspected area of code

5. Java Microbenchmarking Harness (JMH) Framework by Vadym Kazulkin, ip.labs GmbH
Performance Measurement
this.initializeAndFillMyCollection();
final long start=System.nanoTime();
Collections.sort(myCollection);
final long end=System.nanoTime();
System.out.prinltn(“ “ +end-start);
First naive attempt

6. Java Microbenchmarking Harness (JMH) Framework by Vadym Kazulkin, ip.labs GmbH
Performance Measurement
public void measure(final int iterations)
{
for(int i=0; i<iterations; i++)
{
this.initializeAndFillMyCollection();
final long start=System.nanoTime();
Collections.sort(myCollection);
final long end=System.nanoTime();
}
System.out.prinltn(“average time “ +(end-start)/iterations);
}
Second naive attempt

7. Java Microbenchmarking Harness (JMH) Framework by Vadym Kazulkin, ip.labs GmbH
Multiply Performance Measurement
JMH Solution

8. Java Microbenchmarking Harness (JMH) Framework by Vadym Kazulkin, ip.labs GmbH
Multiply Performance Measurement
Corrected JMH Solution

9. Java Microbenchmarking Harness (JMH) Framework by Vadym Kazulkin, ip.labs GmbH
Log Performance Measurement
JMH Solution

10. Java Microbenchmarking Harness (JMH) Framework by Vadym Kazulkin, ip.labs GmbH
Collection Performance Measurement 1
JMH Solution

11. Java Microbenchmarking Harness (JMH) Framework by Vadym Kazulkin, ip.labs GmbH
Collection Performance Measurement 2
JMH Solution

12. Java Microbenchmarking Harness (JMH) Framework by Vadym Kazulkin, ip.labs GmbH
Just-In-Time Compiler Optimizations
• Dead code elimination
• Constant folding
• Loop unrolling
• Devirtualization
• Method inlining
• ….

13. Java Microbenchmarking Harness (JMH) Framework by Vadym Kazulkin, ip.labs GmbH
@CompilerControl

14. Java Microbenchmarking Harness (JMH) Framework by Vadym Kazulkin, ip.labs GmbH
Performance Measurement
pom.xml dependencies

15. Java Microbenchmarking Harness (JMH) Framework by Vadym Kazulkin, ip.labs GmbH
Performance Measurement
pom.xml maven compiler

16. Java Microbenchmarking Harness (JMH) Framework by Vadym Kazulkin, ip.labs GmbH
Performance Measurement
Eclipse -> Project -> Run As

17. Java Microbenchmarking Harness (JMH) Framework by Vadym Kazulkin, ip.labs GmbH
Questions?

18. www.iplabs.de
Thank You!