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Thread: looping through a big number quickly

  1. #1
    Junior Member
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    May 2014
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    Default looping through a big number quickly

    I've thought about this for a bit and when you're using a for loop and you for some reason have to loop through a number like:

    100000000000000000000000000000000000000000000. ( idk why you would have to, but bear with me ) that takes ages with a for loop.

    now i thought about maybe splitting it up in some threads to all add up to the same variable, what would you do?

  2. #2
    Administrator Norm's Avatar
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    May 2010
    Eastern Florida
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    Default Re: looping through a big number quickly

    If the steps being executed inside the loop can be done in parallel in separate threads and the computer the code is executing on has multiple processors so each thread can run on its own processor, then the total elapsed time to do the whole task could be shortened by splitting the work over the threads.
    Using more threads than there are processors can cause contention and lengthen the time.

  3. #3
    Elite Member
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    Jul 2013
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    Default Re: looping through a big number quickly

    Depends on what you want to do. If each iteration must only start after all previous iterations have already finished then you can not use several threads.
    On a single core you cant get much faster then a for-loop.

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