code: private static synchronized ExecutorService initAsyncExecutorService() {
  		if (ASYNC_EXECUTOR_SERVICE == null) {
  			ASYNC_EXECUTOR_SERVICE = java.util.concurrent.Executors.newSingleThreadExecutor(
  				new ThreadFactory() {
  					public Thread newThread(Runnable r) {
  						Thread thread = new Thread(r, "javasimon-async");
  						thread.setDaemon(true);
  						return thread;
  					}
  				});
  		}
  		return ASYNC_EXECUTOR_SERVICE;
  	}
docs: Initializes default single threaded executor service.