Short overview of the most important JMH annotations.
| Name | Description |
|---|---|
Mode.Throughput |
Calculate number of operations in a time unit. |
Mode.AverageTime |
Calculate an average running time. |
Mode.SampleTime |
Calculate how long does it take for a method to run (including percentiles). |
Mode.SingleShotTime |
Just run a method once (useful for cold-testing mode). |
| Any set of these modes | You can specify any set of these modes – the test will be run several times (depending on number of requested modes). |
Mode.All |
All these modes one after another. |
| Name | Description |
|---|---|
Scope.Thread |
This is a default state. An instance will be allocated for each thread running the given test. |
Scope.Benchmark |
An instance will be shared across all threads running the same test. Could be used to test multithreaded performance of a state object (or just mark your benchmark with this scope). |
Scope.Group |
An instance will be allocated per thread group. |
By default JHM forks a new java process for each trial (set of iterations).