Reasons for Parallel Extensions working slowly

Posted by darja on Stack Overflow See other posts from Stack Overflow or by darja
Published on 2010-05-28T08:05:46Z Indexed on 2010/05/28 8:11 UTC
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parallel-extensions

I am trying to make my calculating application faster by using Parallel Extensions. I am new in it, so I have just replaced the main foreach loop with Parallel.ForEach. But calculating became more slow. What can be common reasons for decreasing performance of parallel extensions?

Thanks

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