JMH Benchmark to measure thread launch time overhead

ThreadStartMicro.java

package com.zaxxer.miscmicro;

import java.util.concurrent.TimeUnit;

import org.openjdk.jmh.annotations.Benchmark;
import org.openjdk.jmh.annotations.BenchmarkMode;
import org.openjdk.jmh.annotations.Level;
import org.openjdk.jmh.annotations.Measurement;
import org.openjdk.jmh.annotations.Mode;
import org.openjdk.jmh.annotations.OutputTimeUnit;
import org.openjdk.jmh.annotations.Scope;
import org.openjdk.jmh.annotations.Setup;
import org.openjdk.jmh.annotations.State;

import sun.misc.Unsafe;

@BenchmarkMode(Mode.Throughput)
@OutputTimeUnit(TimeUnit.MILLISECONDS)
@Measurement(time = 2)
@State(Scope.Benchmark)
public class ThreadStartMicro
{
   private static final Unsafe UNSAFE = UnsafeHelper.getUnsafe();

   private volatile Thread benchThread;

   @Setup(Level.Iteration)
   public void startup()
   {
      benchThread = Thread.currentThread();
   }

   @Benchmark
   public long threadStart() throws InterruptedException
   {
      MyThread t = new MyThread();
      t.start();

      if (!t.isStarted())
      {
         UNSAFE.park(false, TimeUnit.MILLISECONDS.toNanos(200));
      }

      return t.getId();
   }

   private class MyThread extends Thread
   {
      private volatile boolean started;

      public void run() {
         started = true;
         UNSAFE.unpark(benchThread);
      };

      public boolean isStarted()
      {
         return started;
      }
   }
}