THIS IS A TEST INSTANCE. ALL YOUR CHANGES WILL BE LOST!!!!
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When translating the CacheTransformation, if the intermediate result of the input has not been cached, a stream node with the sample same parallelism as its input is added to the StreamGraph. Its chaining strategy is set to HEAD so that it will not be chained with the upstream node and the intermediate result will be created.
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During JobGraph translation, multiple StreamNodes may be chaining chained together to form a JobVertex. While translating the StreamGraph to JobGraph, if the translator sees a node whose intermediate result should be cached, it sets the ResultPartitionType of the JobEdge to BLOCKING_PERSISTENT.
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