operator state can only be kept on the heap.
One thing you could try is to add a random value to you data and keyBy on a
composite key that consists of your original key and the random value.
It is important though, that you actually add the random value to your data
to ensure that the extracted key is always the same, i.e., deterministic
with respect to the data.
This should evenly distribute your data and allow you to use keyed MapState.
Hope this helps,
2017-09-19 15:58 GMT+02:00 Tony Wei <[EMAIL PROTECTED]>: