For some reason your pom contains ancient kotlin compiler. I fixed version to 1.4.10 and run it on GraalVM 11. Here are the results:
| Benchmark | Mode | Cnt | Score | Error | Units |
|---|---|---|---|---|---|
| LambdaBenchmark.parallelStreamFunRef | avgt | 5 | 0.203 | 0.012 | s/op |
| LambdaBenchmark.parallelStreamLambda | avgt | 5 | 0.2 | 0.001 | s/op |
| LambdaBenchmark.sequenceFunRef | avgt | 5 | 0.222 | 0.003 | s/op |
| LambdaBenchmark.sequenceLambda | avgt | 5 | 0.224 | 0.016 | s/op |
| LambdaBenchmark.streamFunRef | avgt | 5 | 0.233 | 0.004 | s/op |
| LambdaBenchmark.streamLambda | avgt | 5 | 0.233 | 0.001 | s/op |
The 10% difference is most probably caused by primitive boxing which could be avoided in specialized streams.