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Can't debug python with multiprocessing

See original GitHub issue

@CitizenSanity commented on Fri Dec 20 2019

Using a simple python multiprocessing script like:

from multiprocessing.pool import Pool

def myFunc(funky_var):
    print("This is SPARTA!!!\n\t" + str(funky_var))

myPool = Pool()
lst = range(0,2)

myPool.map(myFunc,lst)
myPool.close()
myPool.join()

I expect my script to run~ but instead get a massive error chain:

root@998da5c4c021:/workspaces/Machine Learning# /usr/local/bin/python /root/.vscode-server/extensions/ms-python.python-2019.11.50794/pythonFiles/ptvsd_launcher.py --default --client --host localhost --port 44471 "/workspaces/Machine Learning/test.py" 
E00000.408: Exception escaped from start_client
            
            Traceback (most recent call last):
              File "/root/.vscode-server/extensions/ms-python.python-2019.11.50794/pythonFiles/lib/python/old_ptvsd/ptvsd/log.py", line 110, in g
                return f(*args, **kwargs)
              File "/root/.vscode-server/extensions/ms-python.python-2019.11.50794/pythonFiles/lib/python/old_ptvsd/ptvsd/pydevd_hooks.py", line 74, in start_client
                sock, start_session = daemon.start_client((host, port))
              File "/root/.vscode-server/extensions/ms-python.python-2019.11.50794/pythonFiles/lib/python/old_ptvsd/ptvsd/daemon.py", line 214, in start_client
                with self.started():
              File "/usr/local/lib/python3.8/contextlib.py", line 113, in __enter__
                return next(self.gen)
              File "/root/.vscode-server/extensions/ms-python.python-2019.11.50794/pythonFiles/lib/python/old_ptvsd/ptvsd/daemon.py", line 110, in started
                self.start()
              File "/root/.vscode-server/extensions/ms-python.python-2019.11.50794/pythonFiles/lib/python/old_ptvsd/ptvsd/daemon.py", line 145, in start
                raise RuntimeError('already started')
            RuntimeError: already started
            

Traceback (most recent call last):

E00000.419: Exception escaped from start_client
            
            Traceback (most recent call last):
              File "/root/.vscode-server/extensions/ms-python.python-2019.11.50794/pythonFiles/lib/python/old_ptvsd/ptvsd/log.py", line 110, in g
                return f(*args, **kwargs)
              File "/root/.vscode-server/extensions/ms-python.python-2019.11.50794/pythonFiles/lib/python/old_ptvsd/ptvsd/pydevd_hooks.py", line 74, in start_client
                sock, start_session = daemon.start_client((host, port))
              File "/root/.vscode-server/extensions/ms-python.python-2019.11.50794/pythonFiles/lib/python/old_ptvsd/ptvsd/daemon.py", line 214, in start_client
                with self.started():
              File "/usr/local/lib/python3.8/contextlib.py", line 113, in __enter__
                return next(self.gen)
              File "/root/.vscode-server/extensions/ms-python.python-2019.11.50794/pythonFiles/lib/python/old_ptvsd/ptvsd/daemon.py", line 110, in started
                self.start()
              File "/root/.vscode-server/extensions/ms-python.python-2019.11.50794/pythonFiles/lib/python/old_ptvsd/ptvsd/daemon.py", line 145, in start
                raise RuntimeError('already started')
            RuntimeError: already started
            

Traceback (most recent call last):


During handling of the above exception, another exception occurred:


E00000.423: Exception escaped from start_client
            
            Traceback (most recent call last):
              File "/root/.vscode-server/extensions/ms-python.python-2019.11.50794/pythonFiles/lib/python/old_ptvsd/ptvsd/log.py", line 110, in g
                return f(*args, **kwargs)
              File "/root/.vscode-server/extensions/ms-python.python-2019.11.50794/pythonFiles/lib/python/old_ptvsd/ptvsd/pydevd_hooks.py", line 74, in start_client
                sock, start_session = daemon.start_client((host, port))
              File "/root/.vscode-server/extensions/ms-python.python-2019.11.50794/pythonFiles/lib/python/old_ptvsd/ptvsd/daemon.py", line 214, in start_client
                with self.started():
              File "/usr/local/lib/python3.8/contextlib.py", line 113, in __enter__
                return next(self.gen)
              File "/root/.vscode-server/extensions/ms-python.python-2019.11.50794/pythonFiles/lib/python/old_ptvsd/ptvsd/daemon.py", line 110, in started
                self.start()
              File "/root/.vscode-server/extensions/ms-python.python-2019.11.50794/pythonFiles/lib/python/old_ptvsd/ptvsd/daemon.py", line 145, in start
                raise RuntimeError('already started')
            RuntimeError: already started
            

Traceback (most recent call last):


During handling of the above exception, another exception occurred:

E00000.426: Exception escaped from start_client
            
            Traceback (most recent call last):
              File "/root/.vscode-server/extensions/ms-python.python-2019.11.50794/pythonFiles/lib/python/old_ptvsd/ptvsd/log.py", line 110, in g
                return f(*args, **kwargs)
              File "/root/.vscode-server/extensions/ms-python.python-2019.11.50794/pythonFiles/lib/python/old_ptvsd/ptvsd/pydevd_hooks.py", line 74, in start_client
                sock, start_session = daemon.start_client((host, port))
              File "/root/.vscode-server/extensions/ms-python.python-2019.11.50794/pythonFiles/lib/python/old_ptvsd/ptvsd/daemon.py", line 214, in start_client
                with self.started():
              File "/usr/local/lib/python3.8/contextlib.py", line 113, in __enter__
                return next(self.gen)
              File "/root/.vscode-server/extensions/ms-python.python-2019.11.50794/pythonFiles/lib/python/old_ptvsd/ptvsd/daemon.py", line 110, in started
                self.start()
              File "/root/.vscode-server/extensions/ms-python.python-2019.11.50794/pythonFiles/lib/python/old_ptvsd/ptvsd/daemon.py", line 145, in start
                raise RuntimeError('already started')
            RuntimeError: already started
            


Traceback (most recent call last):


During handling of the above exception, another exception occurred:


E00000.430: Exception escaped from start_client
            
            Traceback (most recent call last):
              File "/root/.vscode-server/extensions/ms-python.python-2019.11.50794/pythonFiles/lib/python/old_ptvsd/ptvsd/log.py", line 110, in g
                return f(*args, **kwargs)
              File "/root/.vscode-server/extensions/ms-python.python-2019.11.50794/pythonFiles/lib/python/old_ptvsd/ptvsd/pydevd_hooks.py", line 74, in start_client
                sock, start_session = daemon.start_client((host, port))
              File "/root/.vscode-server/extensions/ms-python.python-2019.11.50794/pythonFiles/lib/python/old_ptvsd/ptvsd/daemon.py", line 214, in start_client
                with self.started():
              File "/usr/local/lib/python3.8/contextlib.py", line 113, in __enter__
                return next(self.gen)
              File "/root/.vscode-server/extensions/ms-python.python-2019.11.50794/pythonFiles/lib/python/old_ptvsd/ptvsd/daemon.py", line 110, in started
                self.start()
              File "/root/.vscode-server/extensions/ms-python.python-2019.11.50794/pythonFiles/lib/python/old_ptvsd/ptvsd/daemon.py", line 145, in start
                raise RuntimeError('already started')
            RuntimeError: already started
            

Error in atexit._run_exitfuncs:
Traceback (most recent call last):
Terminated
root@998da5c4c021:/workspaces/Machine Learning# 

During handling of the above exception, another exception occurred:


Error in atexit._run_exitfuncs:
Error in atexit._run_exitfuncs:
Traceback (most recent call last):
E00000.434: Exception escaped from start_client
            
            Traceback (most recent call last):
              File "/root/.vscode-server/extensions/ms-python.python-2019.11.50794/pythonFiles/lib/python/old_ptvsd/ptvsd/log.py", line 110, in g
                return f(*args, **kwargs)
              File "/root/.vscode-server/extensions/ms-python.python-2019.11.50794/pythonFiles/lib/python/old_ptvsd/ptvsd/pydevd_hooks.py", line 74, in start_client
                sock, start_session = daemon.start_client((host, port))
              File "/root/.vscode-server/extensions/ms-python.python-2019.11.50794/pythonFiles/lib/python/old_ptvsd/ptvsd/daemon.py", line 214, in start_client
                with self.started():
              File "/usr/local/lib/python3.8/contextlib.py", line 113, in __enter__
                return next(self.gen)
              File "/root/.vscode-server/extensions/ms-python.python-2019.11.50794/pythonFiles/lib/python/old_ptvsd/ptvsd/daemon.py", line 110, in started
                self.start()
              File "/root/.vscode-server/extensions/ms-python.python-2019.11.50794/pythonFiles/lib/python/old_ptvsd/ptvsd/daemon.py", line 145, in start
                raise RuntimeError('already started')
            RuntimeError: already started
            


Traceback (most recent call last):


During handling of the above exception, another exception occurred:


E00000.438: Exception escaped from start_client
            
            Traceback (most recent call last):
              File "/root/.vscode-server/extensions/ms-python.python-2019.11.50794/pythonFiles/lib/python/old_ptvsd/ptvsd/log.py", line 110, in g
                return f(*args, **kwargs)
              File "/root/.vscode-server/extensions/ms-python.python-2019.11.50794/pythonFiles/lib/python/old_ptvsd/ptvsd/pydevd_hooks.py", line 74, in start_client
                sock, start_session = daemon.start_client((host, port))
              File "/root/.vscode-server/extensions/ms-python.python-2019.11.50794/pythonFiles/lib/python/old_ptvsd/ptvsd/daemon.py", line 214, in start_client
                with self.started():
              File "/usr/local/lib/python3.8/contextlib.py", line 113, in __enter__
                return next(self.gen)
              File "/root/.vscode-server/extensions/ms-python.python-2019.11.50794/pythonFiles/lib/python/old_ptvsd/ptvsd/daemon.py", line 110, in started
                self.start()
              File "/root/.vscode-server/extensions/ms-python.python-2019.11.50794/pythonFiles/lib/python/old_ptvsd/ptvsd/daemon.py", line 145, in start
                raise RuntimeError('already started')
            RuntimeError: already started
            

Error in atexit._run_exitfuncs:
Traceback (most recent call last):
E00000.442: Exception escaped from start_client
            
            Traceback (most recent call last):
              File "/root/.vscode-server/extensions/ms-python.python-2019.11.50794/pythonFiles/lib/python/old_ptvsd/ptvsd/log.py", line 110, in g
                return f(*args, **kwargs)
              File "/root/.vscode-server/extensions/ms-python.python-2019.11.50794/pythonFiles/lib/python/old_ptvsd/ptvsd/pydevd_hooks.py", line 74, in start_client
                sock, start_session = daemon.start_client((host, port))
              File "/root/.vscode-server/extensions/ms-python.python-2019.11.50794/pythonFiles/lib/python/old_ptvsd/ptvsd/daemon.py", line 214, in start_client
                with self.started():
              File "/usr/local/lib/python3.8/contextlib.py", line 113, in __enter__
                return next(self.gen)
              File "/root/.vscode-server/extensions/ms-python.python-2019.11.50794/pythonFiles/lib/python/old_ptvsd/ptvsd/daemon.py", line 110, in started
                self.start()
              File "/root/.vscode-server/extensions/ms-python.python-2019.11.50794/pythonFiles/lib/python/old_ptvsd/ptvsd/daemon.py", line 145, in start
                raise RuntimeError('already started')
            RuntimeError: already started
            

Traceback (most recent call last):


During handling of the above exception, another exception occurred:


Error in atexit._run_exitfuncs:
Error in atexit._run_exitfuncs:
Traceback (most recent call last):

Env: Python3 dev container

Issue Analytics

  • State:closed
  • Created 4 years ago
  • Comments:6 (4 by maintainers)

github_iconTop GitHub Comments

1reaction
karthiknadigcommented, Mar 19, 2020

@ldurka We have addressed this in the latest insiders. The issue was that on remote development scenario we did not pickup the setting to enable the new debugger that supports multiprocessing. Please try it out. You will need to update the version of the extension installed in the remote environment. See instructions here: https://github.com/microsoft/debugpy/issues/59

0reactions
karthiknadigcommented, Mar 19, 2020

Closing this issue since we have addressed this. For anyone running into this issue please follow instructions here: https://github.com/microsoft/debugpy/issues/59

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