@Override
    public <T> Future<T> inParallel(Callable<T> callable) {
      callablesStarting.getAndIncrement();
      Future<T> future = executorService.submit(() -> {
        callablesStarting.getAndDecrement();
        start.await();
        return callable.call();
      });
      futures.add(future);
      return future;
    }
Simple runner that just runs the test in a loop
geode-concurrency-test/src/main/java/org/apache/geode/test/concurrency/loop/LoopRunner.java