Actor have their own state and this is an essencial concept for achieving a near real-time architecture with Akka. Otherwise, a stateless architecture where, for each request, the state needs to be recovered from the persistence layer (database), processed and updated, would fit most of the requirements (and the use of a framework like Akka would be pointless). A stateful architecture is the main reason to use actor model so we can achieve high throughput.
Said the importance of the internal state of the actors, how much information should be kept in this state? Does Akka impose some kind of limitation? Or the JVM memory is the limit?
Is there any guideline on how large the information should be to be maintained within an actor?