Hi all, As mentioned in FLIP-27[1], the proposed SourceReader interface is part of refactoring source interface. AFAIK FLIP-27 has not been voted yet and might still need more time as a whole compared to the
SourceReader discussion which seems more or less converged. We would like to start an initial progress on runtime side based on the SourceReader interface to integrate the execution of SourceReader with existing mailbox thread model[2] in StreamTask. It is one of the steps for finally integrating all the actions in task (processing timer, checkpoint) into unified mailbox model. The benefits are simpler processing logics because only one single thread handles all the actions without concurrent issue, and further getting rid of lock dependency which might cause unfair lock concern in checkpoint process. We still need to support the legacy source in some releases which would probably be used for a while, especially for the scenario of performance concern. Welcome any feedbacks or comments in design doc[3]. [1] https://cwiki.apache.org/confluence/display/FLINK/FLIP-27%3A+Refactor+Source+Interface [2] https://docs.google.com/document/d/1eDpsUKv2FqwZiS1Pm6gYO5eFHScBHfULKmH1-ZEWB4g/edit [3] https://docs.google.com/document/d/13x9M7k1SRqkOFXP0bETcJemIRyJzoqGgkdy11pz5qHM/edit?usp=sharing Best, Zhijiang
