conflateKeys

Conflates each key in the map individually. This buffers emissions, but due to conflation, the maximum number of queued emissions is equal to the number of keys in the map.

Populated is not sent until all outstanding key value pairs have been published, meaning it is possible to receive Removed or multiple Upserts for a single key before the Populated.

Earlier keys are emitted first, so if the upsert events A=a, B=b, A=aa are conflated - the emission order will be A=aa, B=b.