For extending the feature set of the streaming project today we were experimenting with the addition of an IterativeDataStream class, resulting in the following dummy application:
https://github.com/stratosphere/stratosphere-streaming/blob/iterate/stratosphere-streaming-core/src/test/java/eu/stratosphere/streaming/api/IterateTest.java#L80-89 This approach constructs a cyclic JobGraph and exception is thrown for it at the JobManager: https://github.com/apache/incubator-flink/blob/master/stratosphere-runtime/src/main/java/eu/stratosphere/nephele/jobmanager/JobManager.java#L419-424 However when removing this check the JobGraph was created and working as expected. Is the check really needed or should we take another approach when constructing the iterative jobs? Thanks, Marton
