As I know, the time of creation of the execution environment has been slightly modified in the streaming API, which caused that dataStream.getParallelism() and dataStream.env.getDegreeOfParallelism() may return different values. Usage of the former is recommended. In theory, the latter is eliminated from the code, but there might be some more left, hiding. I've recently fixed one in WindowedDataStream. If you encounter problems with the parallelism, it may be the cause.
Peter
