Micro benchmarks are written using JMH. They can be executed by using the jmhJar.
Build the jar:
$ ./gradlew :benchmarks:jmhJar
Then run the benchmarks:
$ java -jar benchmarks/build/libs/crate-benchmarks-all.jar
This will execute all benchmarks which are in benchmarks/src/test/java.
If you want to execute specific benchmarks you can provide a filter argument:
$ java -jar benchmarks/build/libs/crate-benchmarks-all.jar <benchmarkMethodName | benchmarkClassName[.methodName]>
To save the results to a file use the -rf and -rff options:
$ java -jar benchmarks/build/libs/crate-benchmarks-all.jar -rf json -rff benchmarks/build/jmh.json
If you're writing new benchmarks take a look at this JMH introduction and those JMH samples.
Version independent benchmarks which can be written using regular SQL statements are in the crate-benchmarks repository.