def _stop_running_subservers(self):
        if self._filesystem.exists(self._servers_file):
            try:
                json_data = self._filesystem.read_text_file(self._servers_file)
                started_servers = json.loads(json_data)
                for server in started_servers:
                    if self._executive.check_running_pid(server['pid']):
                        _log.warning('Killing server process (protocol: %s , port: %d, pid: %d).' % (server['protocol'], server['port'], server['pid']))
                        self._executive.kill_process(server['pid'])
            finally:
                self._filesystem.remove(self._servers_file)