DateTimeFormatter benchmark

DTFBenchmark.java

package info.unportant.gist.jsr310;

import org.openjdk.jmh.annotations.Benchmark;
import org.openjdk.jmh.annotations.BenchmarkMode;
import org.openjdk.jmh.annotations.Mode;
import org.openjdk.jmh.annotations.OutputTimeUnit;
import org.openjdk.jmh.annotations.Param;
import org.openjdk.jmh.annotations.Scope;
import org.openjdk.jmh.annotations.State;

import java.time.LocalDate;
import java.time.format.DateTimeFormatter;
import java.time.format.DateTimeFormatterBuilder;
import java.time.format.ResolverStyle;
import java.util.concurrent.TimeUnit;
import java.util.function.Supplier;

import static java.time.temporal.ChronoField.DAY_OF_MONTH;
import static java.time.temporal.ChronoField.MONTH_OF_YEAR;
import static java.time.temporal.ChronoField.YEAR;

@BenchmarkMode(Mode.AverageTime)
@OutputTimeUnit(TimeUnit.MICROSECONDS)
@State(Scope.Benchmark)
public class DTFBenchmark {

  private static final DateTimeFormatter withoutOptformatter =
    new DateTimeFormatterBuilder()
      .parseCaseInsensitive()
      .appendValue(YEAR, 4)
      .appendValue(MONTH_OF_YEAR, 2)
      .appendValue(DAY_OF_MONTH, 2)
      .toFormatter()
      .withResolverStyle(ResolverStyle.STRICT);

  private static final DateTimeFormatter patternFormatter =
    DateTimeFormatter.ofPattern("yyyyMMdd").withResolverStyle(ResolverStyle.STRICT);

  @Param(value = {"0", "32", "128"})
  private int stackDepth;

  @Param(value = {"1", "100"})
  private int batchSize;

  LocalDate now = LocalDate.now();

  @Benchmark
  public LocalDate baseline() {
    return recursive(stackDepth, () -> now);
  }

  @Benchmark
  public String basicIsoDate() {
    return recursive(
      stackDepth,
      () -> now.format(DateTimeFormatter.BASIC_ISO_DATE));
  }

  @Benchmark
  public String withoutOpt() {
    return recursive(stackDepth, () -> now.format(withoutOptformatter));
  }

  @Benchmark
  public String ofPattern() {
    return recursive(stackDepth, () -> now.format(patternFormatter));
  }

  private <T> T recursive(int depth, Supplier<T> supplier) {
    if (depth == 0) {
      T t = null;
      for (int i = 0; i < batchSize; i++) {
        t = supplier.get();
      }

      return t;
    }

    return recursive(depth - 1, supplier);
  }
}

Gradle_jmh_config

mh {
    jmhVersion = 1.14

    include = '.*DateTimeFormatter.*'
    warmupForks = 0

    fork = 2
    warmup = '1s'
    warmupIterations = 3
    timeOnIteration = '1s'
    iterations = 6

    failOnError = true
    forceGC = true

    resultsFile = project.file("${project.buildDir}/reports/jmh/results.txt")
    resultFormat = 'JSON'
}

Result_before.txt

Benchmark                         (batchSize)  (stackDepth)  Mode  Cnt     Score    Error  Units
DTFBenchmark.baseline                1             0  avgt   12     0.004 ±  0.001  us/op
DTFBenchmark.baseline                1            32  avgt   12     0.036 ±  0.001  us/op
DTFBenchmark.baseline                1           128  avgt   12     0.156 ±  0.008  us/op
DTFBenchmark.baseline              100             0  avgt   12     0.004 ±  0.001  us/op
DTFBenchmark.baseline              100            32  avgt   12     0.037 ±  0.001  us/op
DTFBenchmark.baseline              100           128  avgt   12     0.128 ±  0.002  us/op
DTFBenchmark.basicIsoDate            1             0  avgt   12     2.525 ±  0.242  us/op
DTFBenchmark.basicIsoDate            1            32  avgt   12     4.893 ±  0.148  us/op
DTFBenchmark.basicIsoDate            1           128  avgt   12    11.512 ±  0.230  us/op
DTFBenchmark.basicIsoDate          100             0  avgt   12   252.686 ± 22.203  us/op
DTFBenchmark.basicIsoDate          100            32  avgt   12   469.255 ±  9.449  us/op
DTFBenchmark.basicIsoDate          100           128  avgt   12  1097.172 ± 28.851  us/op
DTFBenchmark.ofPattern               1             0  avgt   12     0.125 ±  0.003  us/op
DTFBenchmark.ofPattern               1            32  avgt   12     0.176 ±  0.003  us/op
DTFBenchmark.ofPattern               1           128  avgt   12     0.325 ±  0.006  us/op
DTFBenchmark.ofPattern             100             0  avgt   12    11.874 ±  0.273  us/op
DTFBenchmark.ofPattern             100            32  avgt   12    11.734 ±  0.405  us/op
DTFBenchmark.ofPattern             100           128  avgt   12    11.740 ±  0.347  us/op
DTFBenchmark.withoutOpt              1             0  avgt   12     0.124 ±  0.004  us/op
DTFBenchmark.withoutOpt              1            32  avgt   12     0.174 ±  0.005  us/op
DTFBenchmark.withoutOpt              1           128  avgt   12     0.327 ±  0.005  us/op
DTFBenchmark.withoutOpt            100             0  avgt   12    11.891 ±  0.247  us/op
DTFBenchmark.withoutOpt            100            32  avgt   12    11.347 ±  0.221  us/op
DTFBenchmark.withoutOpt            100           128  avgt   12    12.536 ±  1.670  us/op

Results_after.txt

$ export JAVA_HOME=~/Sources/openjdk/jdk9/archived_builds/new/
$ ./gradlew jmh

Benchmark                         (batchSize)  (stackDepth)  Mode  Cnt   Score    Error  Units
DTFBenchmark.baseline                1             0  avgt   12   0.004 ±  0.001  us/op
DTFBenchmark.baseline                1            32  avgt   12   0.036 ±  0.001  us/op
DTFBenchmark.baseline                1           128  avgt   12   0.152 ±  0.007  us/op
DTFBenchmark.baseline              100             0  avgt   12   0.004 ±  0.001  us/op
DTFBenchmark.baseline              100            32  avgt   12   0.036 ±  0.002  us/op
DTFBenchmark.baseline              100           128  avgt   12   0.129 ±  0.002  us/op
DTFBenchmark.basicIsoDate            1             0  avgt   12   0.176 ±  0.009  us/op
DTFBenchmark.basicIsoDate            1            32  avgt   12   0.229 ±  0.007  us/op
DTFBenchmark.basicIsoDate            1           128  avgt   12   0.388 ±  0.013  us/op
DTFBenchmark.basicIsoDate          100             0  avgt   12  16.415 ±  0.310  us/op
DTFBenchmark.basicIsoDate          100            32  avgt   12  18.011 ±  0.997  us/op
DTFBenchmark.basicIsoDate          100           128  avgt   12  16.767 ±  0.376  us/op
DTFBenchmark.ofPattern               1             0  avgt   12   0.122 ±  0.001  us/op
DTFBenchmark.ofPattern               1            32  avgt   12   0.175 ±  0.002  us/op
DTFBenchmark.ofPattern               1           128  avgt   12   0.334 ±  0.006  us/op
DTFBenchmark.ofPattern             100             0  avgt   12  11.398 ±  0.256  us/op
DTFBenchmark.ofPattern             100            32  avgt   12  11.285 ±  0.243  us/op
DTFBenchmark.ofPattern             100           128  avgt   12  11.572 ±  0.370  us/op
DTFBenchmark.withoutOpt              1             0  avgt   12   0.124 ±  0.003  us/op
DTFBenchmark.withoutOpt              1            32  avgt   12   0.181 ±  0.004  us/op
DTFBenchmark.withoutOpt              1           128  avgt   12   0.330 ±  0.007  us/op
DTFBenchmark.withoutOpt            100             0  avgt   12  11.860 ±  0.359  us/op
DTFBenchmark.withoutOpt            100            32  avgt   12  11.630 ±  0.401  us/op
DTFBenchmark.withoutOpt            100           128  avgt   12  11.749 ±  0.259  us/op