fio_visualizer.py can not ending for fio run

[heysion]

fio.conf

[global]
ioengine=sync
thread=1
runtime=60
size=1g
filename=/tmp/111/test.raw

[read4k-seq]
group_reporting
bs=4k
rw=read
numjobs=1

[write4k-seq]
group_reporting
bs=4k
rw=write
numjobs=1

error message & click stop button output message

Traceback (most recent call last):
  File "./fio_visualizer.py", line 620, in <lambda>
    timer.timeout.connect(lambda: update(fio_all_data, parsing_thread, exit_code[0], timer))
  File "./fio_visualizer.py", line 662, in update
    fio_process_output, fio_process_error = fio_process.communicate()
  File "/usr/lib/python2.7/subprocess.py", line 483, in communicate
    return self._communicate(input)
  File "/usr/lib/python2.7/subprocess.py", line 1124, in _communicate
    stdout, stderr = self._communicate_with_poll(input)
  File "/usr/lib/python2.7/subprocess.py", line 1169, in _communicate_with_poll
    register_and_append(self.stdout, select_POLLIN_POLLPRI)
  File "/usr/lib/python2.7/subprocess.py", line 1156, in register_and_append
    poller.register(file_obj.fileno(), eventmask)
ValueError: I/O operation on closed file
Traceback (most recent call last):
  File "./fio_visualizer.py", line 620, in <lambda>
    timer.timeout.connect(lambda: update(fio_all_data, parsing_thread, exit_code[0], timer))
  File "./fio_visualizer.py", line 662, in update
    fio_process_output, fio_process_error = fio_process.communicate()
  File "/usr/lib/python2.7/subprocess.py", line 483, in communicate
    return self._communicate(input)
  File "/usr/lib/python2.7/subprocess.py", line 1124, in _communicate
    stdout, stderr = self._communicate_with_poll(input)
  File "/usr/lib/python2.7/subprocess.py", line 1169, in _communicate_with_poll
    register_and_append(self.stdout, select_POLLIN_POLLPRI)
  File "/usr/lib/python2.7/subprocess.py", line 1156, in register_and_append
    poller.register(file_obj.fileno(), eventmask)
ValueError: I/O operation on closed file