python multiprocessing on windows, if __name__ == “__main__”

by

You do not have to call Process() from the “top level” of the module.
It is perfectly fine to call Process from a class method.

The only caveat is that you can not allow Process() to be called if or when the module is imported.

Since Windows has no fork, the multiprocessing module starts a new Python process and imports the calling module. If Process() gets called upon import, then this sets off an infinite succession of new processes (or until your machine runs out of resources). This is the reason for hiding calls to Process() inside 

if __name__ == "__main__"

since statements inside this if-statement will not get called upon import.

More Related Contents:

  1. Multiprocessing vs Threading Python [duplicate]
  2. multiprocessing: How do I share a dict among multiple processes?
  3. multiprocessing global variable updates not returned to parent
  4. How should I log while using multiprocessing in Python?
  5. multiprocessing: sharing a large read-only object between processes?
  6. Python sharing a lock between processes
  7. Python multiprocessing safely writing to a file
  8. Compulsory usage of if __name__==”__main__” in windows while using multiprocessing [duplicate]
  9. Multiprocessing – Pipe vs Queue
  10. Multiprocessing working in Python but not in iPython
  11. Concurrent.futures vs Multiprocessing in Python 3
  12. Parallelizing a Numpy vector operation
  13. multiprocessing.pool.MaybeEncodingError: ‘TypeError(“cannot serialize ‘_io.BufferedReader’ object”,)’
  14. High Memory Usage Using Python Multiprocessing
  15. “chunksize” parameter in multiprocessing.Pool.map
  16. Connection problems with SQLAlchemy and multiple processes
  17. OSError 38 [Errno 38] with multiprocessing
  18. Can multiprocessing Process class be run from IDLE
  19. multiprocessing.Pool – PicklingError: Can’t pickle : attribute lookup thread.lock failed
  20. Python multiprocess profiling
  21. What’s the difference between ThreadPool vs Pool in the multiprocessing module?
  22. how to to terminate process using python’s multiprocessing
  23. Using python multiprocessing Pool in the terminal and in code modules for Django or Flask
  24. Using 100% of all cores with the multiprocessing module
  25. Mix Python Twisted with multiprocessing?
  26. Python multiprocessing memory usage
  27. How to signal slots in a GUI from a different process?
  28. How to limit number of CPU’s used by a python script w/o terminal or multiprocessing library?
  29. Multiprocessing pool with an iterator
  30. multiprocessing: How can I ʀᴇʟɪᴀʙʟʏ redirect stdout from a child process?

Leave a Comment