ProcessPoolExecutor卡住,ThreadPool Executor没有

我有一个应用程序可以让我选择是使用线程还是进程:

def _get_future(self, workers):
        if self.config == "threadpool":
            self.logger.debug("using thread pools")
            executor = ThreadPoolExecutor(max_workers=workers)
        else:
            self.logger.debug("using process pools")
            executor = ProcessPoolExecutor(max_workers=workers)
        return executor

self.executor = self._get_future()
for component in components:
    self.logger.debug("submitting {} to future ".format(component))
    self.future_components.append(self.executor.submit
                                              (self._send_component, component))

    # Wait for all tasks to finish
while self.future_components:
    self.future_components.pop().result()

当我使用进程时,我的应用程序就会卡住。从未调用\u send \u component方法。当我用线的时候一切都很好。