java8中parallelStream性能测试及结果分析

@BenchmarkMode(Mode.AverageTime)@OutputTimeUnit(TimeUnit.NANOSECONDS)@Warmup(iterations = 5, time = 3, timeUnit = TimeUnit.SECONDS)@Measurement(iterations = 20, time = 3, timeUnit = TimeUnit.SECONDS)@Fork(1)@State(Scope.Benchmark)public class StreamBenchTest {  List<String> data = new ArrayList<>();  @Setup  public void init() {    // prepare    for(int i=0;i<100;i++){      data.add(UUID.randomUUID().toString());    }  }  @TearDown  public void destory() {    // destory  }  @Benchmark  public void benchStream(){    data.stream().forEach(e -> {      e.getBytes();      try {        Thread.sleep(10);      } catch (InterruptedException e1) {        e1.printStackTrace();      }    });  }  @Benchmark  public void benchParallelStream(){    data.parallelStream().forEach(e -> {      e.getBytes();      try {        Thread.sleep(10);      } catch (InterruptedException e1) {        e1.printStackTrace();      }    });  }  public static void main(String[] args) throws RunnerException {    Options opt = new OptionsBuilder()        .include(".*" +StreamBenchTest.class.getSimpleName()+ ".*")        .forks(1)        .build();    new Runner(opt).run();  }}

# Run complete. Total time: 00:02:44Benchmark              Mode Cnt      Score     Error UnitsStreamBenchTest.benchParallelStream avgt  20  155868805.437 ± 1509175.840 ns/opStreamBenchTest.benchStream     avgt  20 1147570372.950 ± 6138494.414 ns/op

Benchmark              Mode Cnt      Score     Error UnitsStreamBenchTest.benchParallelStream avgt  20  414230854.631 ± 725294.455 ns/opStreamBenchTest.benchStream     avgt  20 3107250608.500 ± 4805037.628 ns/op