thread.interrupt(); // try to get them to exit
    }
    threads.clear();
  }

  @Footprint
  Object measureSize() {
    return executor;
  }

  @Benchmark
  int timeUncontendedExecute(int reps) {
    Executor executor = this.executor;
    CountingRunnable countingRunnable = this.countingRunnable;
    for (int i = 0; i < reps; i++) {
      executor.execute(countingRunnable);
    }