AgctProfilingFails.java

package safepoint.profiling;

import java.util.Random;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.locks.LockSupport;
import java.util.zip.Adler32;
import java.util.zip.CRC32;

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.Setup;
import org.openjdk.jmh.annotations.State;

@BenchmarkMode(Mode.AverageTime)
@OutputTimeUnit(TimeUnit.NANOSECONDS)
@State(Scope.Thread)
public class AgctProfilingFails {
  @Param("1000")
  int size;
  CRC32 crc = new CRC32();
  Adler32 adler = new Adler32();

  byte[] buffer;
  byte[] dst;
  boolean result;

  @Setup
  public final void setup() {
    Random randomGenerator = new Random(666);
    buffer = new byte[size];
    randomGenerator.nextBytes(buffer);
    dst = new byte[size];
  }

  @Benchmark
  public int systemArrayCopy() {
    System.arraycopy(buffer, 0, dst, 0, buffer.length);
    return dst[buffer.length-1];
  }

  @Benchmark
  public long adler32(){
    adler.update(buffer);
    return adler.getValue();
  }

  @Benchmark
  public long crc32(){
    crc.update(buffer);
    return crc.getValue();
  }

  @Benchmark
  public long adler32AndPark() {
    adler.update(buffer);
    LockSupport.parkNanos(1);
    return adler.getValue();
  }
}