Microbenchmarks that (in)validate CreednGo rules.

This repository is a Gradle project configured with the JMH benchmarking framework.

Rules often suggest an alternative way of writing small pieces of code. Measuring the effect of a small and isolated amount of code is hard, we need to be cautious. See How NOT to write a microbenchmark, Avoiding Benchmarking Pitfalls on the JVM, the OpenJDK wiki page So, you want to write a microbenchmark, and many others.

To run or create benchmarks, you need a recent JDK. You can use sdkman to setup your environment easily.

By default, this project uses Java 21 (see below to change that).

• Create a new public class in microbenchs/src/jmh/java/org/greencodeinitiative/creedngo.
• Create multiple methods with the @Benchmark annotation to compare different scenarios (for example one where the code rule is applied, one where it is not). See Example.java.

Use the bench.sh script, which is a wrapper around the JMH jar file. Run ./bench.sh -h too see the available JMH options.

To run a single benchmark function:

./bench.sh BenchmarkClass.benchmarkMethod

To run all the benchmarks in a given class:

./bench.sh BenchmarkClass

The benchmark results are printed to stdout and stored in microbenchs/build/reports/jmh/result.json.

Edit build.gradle.kts and change JavaLanguageVersion.of(XX).

It is recommended to use a recent version of Java (>= 17), as it will benefit from the new compiler blackholes. However, for testing purposes, you may want to run your benchmarks with an older version.