Github user mxm commented on the pull request:
https://github.com/apache/flink/pull/372#issuecomment-95855310
Just saying that a prefix helps to identify output, even if everything is
printed on the client. Additionally, including the task id in the output can be
useful for debugging.
---
If your project is set up for it, you can reply to this email and have your
reply appear on GitHub as well. If your project does not have this feature
enabled and wishes so, or if the feature is enabled but not working, please
contact infrastructure at [email protected] or file a JIRA ticket
with INFRA.
---