JRuby InvokeDynamic is designed for improving performance, however, what I observed in real environment (especially running Rails) was decreasing performance.
You can enable invokedynamic use on Java 7, but it is disabled normally due to JVM issues. On Java 8 builds, it is enabled by default.
see https://github.com/jruby/jruby/wiki/PerformanceTuning for more details
By Java options: -Djruby.compile.invokedynamic=false
Test environment:
- Standalone Go server with some simple configured pipelines: 5 simple pipelines configured (see Go server config)
- One Agent connected to server, and no job is scheduled. All pipelines built once and green.
- Go server is built from latest master branch
- Java version: 1.8.0_40
- OS: Mac 10.11.2
Test tool: Apache benchmarking tool AB Test cases:
- 1000 requests, 1 concurrency, example: ab -n 1000 -c 1 http://localhost:8153/go/admin/pipelines//stages/defaultStage/settings
- 1000 requests, 20 concurrency, example: ab -n 1000 -c 20 http://localhost:8153/go/admin/pipelines//stages/defaultStage/settings Test pages:
- stage settings page (has 3 jobs configured in the stage)
- pipelines.json (xhr request on pipeline dashboard page)
Test result:
command: ab -n 1000 -c 20 http://localhost:8153/go/admin/pipelines/hello/stages/defaultStage/settings
| JRuby invoke dynamic | Time taken for tests | Time per request (mean) |
|---|---|---|
| off | 1.067 sec | 21.345ms |
| on | 3.775 sec | 75.510ms |
command: ab -n 1000 -c 20 http://localhost:8153/go/pipelines.json
| JRuby invoke dynamic | Time taken for tests | Time per request (mean) |
|---|---|---|
| off | 0.945 sec | 18.898ms |
| on | 1.205 sec | 24.095ms |
command: ab -n 1000 -c 1 http://localhost:8153/go/admin/pipelines/hello/stages/defaultStage/settings
| JRuby invoke dynamic | Time taken for tests | Time per request (mean) |
|---|---|---|
| off | 4.852 sec | 4.852ms |
| on | 9.800 sec | 9.800ms |
command: ab -n 1000 -c 1 http://localhost:8153/go/pipelines.json
| JRuby invoke dynamic | Time taken for tests | Time per request (mean) |
|---|---|---|
| off | 4.500 sec | 4.500ms |
| on | 5.222 sec | 5.222ms |
Another noticable performance difference in test is JVM warm-up speed. It was a lot faster to get stable response time when JRuby invoke dynamic is off.
You can go to https://github.com/xli/gocd-invokedynamic-testresult to checkout full AB test reports mentioned above
I only give 2 page tests result above for comparison. But most of pages should have similar performance difference with pipelines.json request.
Turning off JRuby invoke dynamic feature on Java 8 has significant performance improvement. More and more Go user will move to Java 8 as Oracle Java 7 no longer has public updates anymore. So we should turn it off by default on Go Server.