problem with simple multiprocessing script on OS X

Darren Dale dsdale24 at gmail.com
Tue Aug 24 15:31:00 EDT 2010


On Aug 23, 9:58 am, Darren Dale <dsdal... at gmail.com> wrote:
> The following script runs without problems on Ubuntu and Windows 7.
> h5py is a package wrapping the hdf5 library (http://code.google.com/p/
> h5py/):
>
> from multiprocessing import Pool
> import h5py
>
> def update(i):
>     print i
>
> def f(i):
>     "hello foo"
>     return i*i
>
> if __name__ == '__main__':
>     pool = Pool()
>     for i in range(10):
>         pool.apply_async(f, [i], callback=update)
>     pool.close()
>     pool.join()
>
> On OS X 10.6 (tested using python-2.6.5 from MacPorts), I have to
> comment out the as-yet unused h5py import, otherwise I get a
> traceback:
>
> Exception in thread Thread-1:
> Traceback (most recent call last):
>   File "/opt/local/Library/Frameworks/Python.framework/Versions/2.6/
> lib/python2.6/threading.py", line 532, in __bootstrap_inner
>     self.run()
>   File "/opt/local/Library/Frameworks/Python.framework/Versions/2.6/
> lib/python2.6/threading.py", line 484, in run
>     self.__target(*self.__args, **self.__kwargs)
>   File "/opt/local/Library/Frameworks/Python.framework/Versions/2.6/
> lib/python2.6/multiprocessing/pool.py", line 226, in _handle_tasks
>     put(task)
> PicklingError: Can't pickle <type 'function'>: attribute lookup
> __builtin__.function failed


This is a really critical bug for me, but I'm not sure how to proceed.
Can I file a bug report on the python bugtracker if the only code I
can come up with to illustrate the problem requires a lame import of a
third party module?



More information about the Python-list mailing list