Hi, Nice to see the progress of Stateful functions.
I have a few questions that I hope you can reply to. My first question is regarding the newly implemented StatefulFunctionDataStreamBuilder. Is there anything to pay attention to if one first union a couple of streams and performs a sort via a keyBy and a KeyedProcessFunction before dispatching the messages to via RoutableMessage? In this sorting I'm using a mapstate and I guess my question is if one can freely mix Flink core with SF's code with regards to performance, fault-tolerance, and checkpointing? I'm unable to use Protobuf so POJO's is going to be processed. Is there a large performance impact of using Pojos instead of protos in SF? Also I wonder if there's going to be a severe performance penalty if I had a function that was called very often lets say 1000 a second and hold a PersistentAppendingBuffer with those objects appended for each message? Then when the 1001:st message comes or a timetrigger kicks in, I would write everything to disk and delete the state. Would the appendingBuffer be de-/serialized for each function invocation? If yes, is there any workaround for this so the data is just held in RAM? Thanks, Regards Dan -- Sent from: http://apache-flink-user-mailing-list-archive.2336050.n4.nabble.com/
