How to pick a chunksize for python multiprocessing with large datasets

Posted by Sandro on Stack Overflow See other posts from Stack Overflow or by Sandro
Published on 2010-04-24T20:09:12Z Indexed on 2010/04/24 20:13 UTC
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Filed under:

python

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multiprocessing

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chunksize

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large-data-volumes

I am attempting to to use python to gain some performance on a task that can be highly parallelized using http://docs.python.org/library/multiprocessing.

When looking at their library they say to use chunk size for very long iterables. Now, my iterable is not long, one of the dicts that it contains is huge: ~100000 entries, with tuples as keys and numpy arrays for values.

How would I set the chunksize to handle this and how can I transfer this data quickly?

Thank you.

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