tikinter issue: RuntimeError: main thread is not in main loop

[phcerdan]

Describe the bug
I got a tkinter runtime error related with threads when locally running the spleen_segmentation_3d.ipynb in the epoch cell.

epoch 12/600
1/16, train_loss: 0.5761
2/16, train_loss: 0.5969
3/16, train_loss: 0.4487
4/16, train_loss: 0.5615
Exception ignored in: <function Image.__del__ at 0x7f1d2ec71ca0>
Traceback (most recent call last):
  File "/usr/lib/python3.8/tkinter/__init__.py", line 4014, in __del__
    self.tk.call('image', 'delete', self.name)
RuntimeError: main thread is not in main loop
Exception ignored in: <function Image.__del__ at 0x7f1d2ec71ca0>
Traceback (most recent call last):
  File "/usr/lib/python3.8/tkinter/__init__.py", line 4014, in __del__
    self.tk.call('image', 'delete', self.name)
RuntimeError: main thread is not in main loop
5/16, train_loss: 0.5464
Exception ignored in: <function Image.__del__ at 0x7f1d2ec71ca0>
Traceback (most recent call last):
  File "/usr/lib/python3.8/tkinter/__init__.py", line 4014, in __del__
    self.tk.call('image', 'delete', self.name)
RuntimeError: main thread is not in main loop
Exception ignored in: <function Image.__del__ at 0x7f1d2ec71ca0>
Traceback (most recent call last):
  File "/usr/lib/python3.8/tkinter/__init__.py", line 4014, in __del__
    self.tk.call('image', 'delete', self.name)
RuntimeError: main thread is not in main loop
Exception ignored in: <function Image.__del__ at 0x7f1d2ec71ca0>
Traceback (most recent call last):
  File "/usr/lib/python3.8/tkinter/__init__.py", line 4014, in __del__
    self.tk.call('image', 'delete', self.name)
RuntimeError: main thread is not in main loop
Exception ignored in: <function Image.__del__ at 0x7f1d2ec71ca0>
Traceback (most recent call last):
  File "/usr/lib/python3.8/tkinter/__init__.py", line 4014, in __del__
    self.tk.call('image', 'delete', self.name)
RuntimeError: main thread is not in main loop
Exception ignored in: <function Image.__del__ at 0x7f1d2ec71ca0>
Traceback (most recent call last):
  File "/usr/lib/python3.8/tkinter/__init__.py", line 4014, in __del__
    self.tk.call('image', 'delete', self.name)
RuntimeError: main thread is not in main loop
Exception ignored in: <function Image.__del__ at 0x7f1d2ec71ca0>
Traceback (most recent call last):
  File "/usr/lib/python3.8/tkinter/__init__.py", line 4014, in __del__
    self.tk.call('image', 'delete', self.name)
RuntimeError: main thread is not in main loop
Exception ignored in: <function Variable.__del__ at 0x7f1d2ec583a0>
Traceback (most recent call last):
  File "/usr/lib/python3.8/tkinter/__init__.py", line 351, in __del__
    if self._tk.getboolean(self._tk.call("info", "exists", self._name)):
RuntimeError: main thread is not in main loop
Exception ignored in: <function Variable.__del__ at 0x7f1d2ec583a0>
Traceback (most recent call last):
  File "/usr/lib/python3.8/tkinter/__init__.py", line 351, in __del__
    if self._tk.getboolean(self._tk.call("info", "exists", self._name)):
RuntimeError: main thread is not in main loop
Exception ignored in: <function Variable.__del__ at 0x7f1d2ec583a0>
Traceback (most recent call last):
  File "/usr/lib/python3.8/tkinter/__init__.py", line 351, in __del__
    if self._tk.getboolean(self._tk.call("info", "exists", self._name)):
RuntimeError: main thread is not in main loop
Exception ignored in: <function Variable.__del__ at 0x7f1d2ec583a0>
Traceback (most recent call last):
  File "/usr/lib/python3.8/tkinter/__init__.py", line 351, in __del__
    if self._tk.getboolean(self._tk.call("info", "exists", self._name)):
RuntimeError: main thread is not in main loop
Exception ignored in: <function Image.__del__ at 0x7f1d2ec71ca0>
Traceback (most recent call last):
  File "/usr/lib/python3.8/tkinter/__init__.py", line 4014, in __del__
    self.tk.call('image', 'delete', self.name)
RuntimeError: main thread is not in main loop
Exception ignored in: <function Image.__del__ at 0x7f1d2ec71ca0>
Traceback (most recent call last):
  File "/usr/lib/python3.8/tkinter/__init__.py", line 4014, in __del__
    self.tk.call('image', 'delete', self.name)
RuntimeError: main thread is not in main loop
Exception ignored in: <function Image.__del__ at 0x7f1d2ec71ca0>
Traceback (most recent call last):
  File "/usr/lib/python3.8/tkinter/__init__.py", line 4014, in __del__
    self.tk.call('image', 'delete', self.name)
RuntimeError: main thread is not in main loop
Exception ignored in: <function Image.__del__ at 0x7f1d2ec71ca0>
Traceback (most recent call last):
  File "/usr/lib/python3.8/tkinter/__init__.py", line 4014, in __del__
    self.tk.call('image', 'delete', self.name)
RuntimeError: main thread is not in main loop
Exception ignored in: <function Variable.__del__ at 0x7f1d2ec583a0>
Traceback (most recent call last):
  File "/usr/lib/python3.8/tkinter/__init__.py", line 351, in __del__
    if self._tk.getboolean(self._tk.call("info", "exists", self._name)):
RuntimeError: main thread is not in main loop
Exception ignored in: <function Variable.__del__ at 0x7f1d2ec583a0>
Traceback (most recent call last):
  File "/usr/lib/python3.8/tkinter/__init__.py", line 351, in __del__
    if self._tk.getboolean(self._tk.call("info", "exists", self._name)):
RuntimeError: main thread is not in main loop
Exception ignored in: <function Variable.__del__ at 0x7f1d2ec583a0>
Traceback (most recent call last):
  File "/usr/lib/python3.8/tkinter/__init__.py", line 351, in __del__
    if self._tk.getboolean(self._tk.call("info", "exists", self._name)):
RuntimeError: main thread is not in main loop
Exception ignored in: <function Variable.__del__ at 0x7f1d2ec583a0>
Traceback (most recent call last):
  File "/usr/lib/python3.8/tkinter/__init__.py", line 351, in __del__
    if self._tk.getboolean(self._tk.call("info", "exists", self._name)):
RuntimeError: main thread is not in main loop
Exception ignored in: <function Image.__del__ at 0x7f1d2ec71ca0>
Traceback (most recent call last):
  File "/usr/lib/python3.8/tkinter/__init__.py", line 4014, in __del__
    self.tk.call('image', 'delete', self.name)
RuntimeError: main thread is not in main loop
Exception ignored in: <function Image.__del__ at 0x7f1d2ec71ca0>
Traceback (most recent call last):
  File "/usr/lib/python3.8/tkinter/__init__.py", line 4014, in __del__
    self.tk.call('image', 'delete', self.name)
RuntimeError: main thread is not in main loop
Exception ignored in: <function Image.__del__ at 0x7f1d2ec71ca0>
Traceback (most recent call last):
  File "/usr/lib/python3.8/tkinter/__init__.py", line 4014, in __del__
    self.tk.call('image', 'delete', self.name)
RuntimeError: main thread is not in main loop
Exception ignored in: <function Image.__del__ at 0x7f1d2ec71ca0>
Traceback (most recent call last):
  File "/usr/lib/python3.8/tkinter/__init__.py", line 4014, in __del__
    self.tk.call('image', 'delete', self.name)
RuntimeError: main thread is not in main loop
Exception ignored in: <function Image.__del__ at 0x7f1d2ec71ca0>
Traceback (most recent call last):
  File "/usr/lib/python3.8/tkinter/__init__.py", line 4014, in __del__
    self.tk.call('image', 'delete', self.name)
RuntimeError: main thread is not in main loop
Exception ignored in: <function Image.__del__ at 0x7f1d2ec71ca0>
Traceback (most recent call last):
  File "/usr/lib/python3.8/tkinter/__init__.py", line 4014, in __del__
    self.tk.call('image', 'delete', self.name)
RuntimeError: main thread is not in main loop
Exception ignored in: <function Image.__del__ at 0x7f1d2ec71ca0>
Traceback (most recent call last):
  File "/usr/lib/python3.8/tkinter/__init__.py", line 4014, in __del__
    self.tk.call('image', 'delete', self.name)
RuntimeError: main thread is not in main loop
Exception ignored in: <function Image.__del__ at 0x7f1d2ec71ca0>
Traceback (most recent call last):
  File "/usr/lib/python3.8/tkinter/__init__.py", line 4014, in __del__
    self.tk.call('image', 'delete', self.name)
RuntimeError: main thread is not in main loop
Exception ignored in: <function Image.__del__ at 0x7f1d2ec71ca0>
Traceback (most recent call last):
  File "/usr/lib/python3.8/tkinter/__init__.py", line 4014, in __del__
    self.tk.call('image', 'delete', self.name)
RuntimeError: main thread is not in main loop
Exception ignored in: <function Image.__del__ at 0x7f1d2ec71ca0>
Traceback (most recent call last):
  File "/usr/lib/python3.8/tkinter/__init__.py", line 4014, in __del__
    self.tk.call('image', 'delete', self.name)
RuntimeError: main thread is not in main loop
Exception ignored in: <function Image.__del__ at 0x7f1d2ec71ca0>
Traceback (most recent call last):
  File "/usr/lib/python3.8/tkinter/__init__.py", line 4014, in __del__
    self.tk.call('image', 'delete', self.name)
RuntimeError: main thread is not in main loop
Exception ignored in: <function Image.__del__ at 0x7f1d2ec71ca0>
Traceback (most recent call last):
  File "/usr/lib/python3.8/tkinter/__init__.py", line 4014, in __del__
    self.tk.call('image', 'delete', self.name)
RuntimeError: main thread is not in main loop
Exception ignored in: <function Image.__del__ at 0x7f1d2ec71ca0>
Traceback (most recent call last):
  File "/usr/lib/python3.8/tkinter/__init__.py", line 4014, in __del__
    self.tk.call('image', 'delete', self.name)
RuntimeError: main thread is not in main loop
Exception ignored in: <function Image.__del__ at 0x7f1d2ec71ca0>
Traceback (most recent call last):
  File "/usr/lib/python3.8/tkinter/__init__.py", line 4014, in __del__
    self.tk.call('image', 'delete', self.name)
RuntimeError: main thread is not in main loop
Exception ignored in: <function Image.__del__ at 0x7f1d2ec71ca0>
Traceback (most recent call last):
  File "/usr/lib/python3.8/tkinter/__init__.py", line 4014, in __del__
    self.tk.call('image', 'delete', self.name)
RuntimeError: main thread is not in main loop
Exception ignored in: <function Image.__del__ at 0x7f1d2ec71ca0>
Traceback (most recent call last):
  File "/usr/lib/python3.8/tkinter/__init__.py", line 4014, in __del__
    self.tk.call('image', 'delete', self.name)
RuntimeError: main thread is not in main loop
Exception ignored in: <function Image.__del__ at 0x7f1d2ec71ca0>
Traceback (most recent call last):
  File "/usr/lib/python3.8/tkinter/__init__.py", line 4014, in __del__
    self.tk.call('image', 'delete', self.name)
RuntimeError: main thread is not in main loop
Tcl_AsyncDelete: async handler deleted by the wrong thread
Exception ignored in: <function Image.__del__ at 0x7f1d2ec71ca0>
Traceback (most recent call last):
  File "/usr/lib/python3.8/tkinter/__init__.py", line 4014, in __del__
    self.tk.call('image', 'delete', self.name)
RuntimeError: main thread is not in main loop
Tcl_AsyncDelete: async handler deleted by the wrong thread
Exception ignored in: <function Image.__del__ at 0x7f1d2ec71ca0>
Traceback (most recent call last):
  File "/usr/lib/python3.8/tkinter/__init__.py", line 4014, in __del__
    self.tk.call('image', 'delete', self.name)
RuntimeError: main thread is not in main loop
Tcl_AsyncDelete: async handler deleted by the wrong thread
Exception ignored in: <function Image.__del__ at 0x7f1d2ec71ca0>
Traceback (most recent call last):
  File "/usr/lib/python3.8/tkinter/__init__.py", line 4014, in __del__
    self.tk.call('image', 'delete', self.name)
RuntimeError: main thread is not in main loop
Tcl_AsyncDelete: async handler deleted by the wrong thread
Traceback (most recent call last):
  File "/home/phc/.virtualenvs/monai/lib/python3.8/site-packages/torch/utils/data/dataloader.py", line 872, in _try_get_data
    data = self._data_queue.get(timeout=timeout)
  File "/usr/lib/python3.8/multiprocessing/queues.py", line 107, in get
    if not self._poll(timeout):
  File "/usr/lib/python3.8/multiprocessing/connection.py", line 257, in poll
    return self._poll(timeout)
  File "/usr/lib/python3.8/multiprocessing/connection.py", line 424, in _poll
    r = wait([self], timeout)
  File "/usr/lib/python3.8/multiprocessing/connection.py", line 931, in wait
    ready = selector.select(timeout)
  File "/usr/lib/python3.8/selectors.py", line 415, in select
    fd_event_list = self._selector.poll(timeout)
  File "/home/phc/.virtualenvs/monai/lib/python3.8/site-packages/torch/utils/data/_utils/signal_handling.py", line 66, in handler
    _error_if_any_worker_fails()
RuntimeError: DataLoader worker (pid 355179) is killed by signal: Aborted.

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "spleen_segmentation_3d.py", line 268, in <module>
    for batch_data in train_loader:
  File "/home/phc/.virtualenvs/monai/lib/python3.8/site-packages/torch/utils/data/dataloader.py", line 435, in __next__
    data = self._next_data()
  File "/home/phc/.virtualenvs/monai/lib/python3.8/site-packages/torch/utils/data/dataloader.py", line 1068, in _next_data
    idx, data = self._get_data()
  File "/home/phc/.virtualenvs/monai/lib/python3.8/site-packages/torch/utils/data/dataloader.py", line 1034, in _get_data
    success, data = self._try_get_data()
  File "/home/phc/.virtualenvs/monai/lib/python3.8/site-packages/torch/utils/data/dataloader.py", line 885, in _try_get_data
    raise RuntimeError('DataLoader worker (pid(s) {}) exited unexpectedly'.format(pids_str)) from e
RuntimeError: DataLoader worker (pid(s) 355179) exited unexpectedly

Environment (please complete the following information):

• OS: Linux (arch)
• Python version: 3.8.6
• MONAI version [e.g. git commit hash] 0.4.0
• CUDA/cuDNN version: 11.1
• GPU models and configuration: 3090

Additional context
Sorry for the brevitiy of the report. The notebook is run as a python script using jupytext (converts ipynb to py).

[Nic-Ma]

Hi @phcerdan ,

Thanks for your interest here and experiments.
It seems like something unstable in your environment? Did you always get this error?

Thanks.

[phcerdan]

My error is related with this SO question: https://stackoverflow.com/questions/27147300/matplotlib-tcl-asyncdelete-async-handler-deleted-by-the-wrong-thread

I am using the console, not the web UI, nor an IDE. I was closing the matplotlib pop-up window pressing the "x" button. If I close it using the key q, the error is gone.

Nothing to do with monai, closing.