Noticing that Flink takes very long inside collect(..) due to Avro serialization that relies on ReflectDatumWriter & GenericDatumWriter. The object being serialized here is an Avro object that implements SpecificRecordBase. It is somewhat about large (~50Kb) and complex.
Looking for a way to use SpecificDatumWriter for the serialization instead of the generic/reflection based stuff to speed it up. But don't see a way to influence that change.
