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Updating variables in Multi-processing
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Updating variables in Multi-processing
#11
I think that's because you're trying to access the value within the Manager, after the manager's been cleaned up from the with block. Try this:
if __name__ == '__main__':
    with multiprocessing.Manager() as manager:
        with multiprocessing.Pool(6) as p:
            error_value = manager.Value('i', 0)
            args = itertools.product(input_list, [error_value])
            results = p.map(get_data, args)
 
        for result in results:
              ...
        print("Total errors:", error_value.value)
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#12
(Feb-12-2021, 04:28 PM)nilamo Wrote: I think that's because you're trying to access the value within the Manager, after the manager's been cleaned up from the with block. Try this:
if __name__ == '__main__':
    with multiprocessing.Manager() as manager:
        with multiprocessing.Pool(6) as p:
            error_value = manager.Value('i', 0)
            args = itertools.product(input_list, [error_value])
            results = p.map(get_data, args)
 
        for result in results:
              ...
        print("Total errors:", error_value.value)


I ended up putting the print statement immediately after the results = p.map(get_data, args) just to be sure and it worked!!

What a difference a small change makes! LOL

Thanks again for your help.
Reply


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