Maximum number of unconfirmed messages, that this actor is allowed to hold in the memory. if this number is exceeded, Deliver(ActorPath, Func< Int64, Object> , Boolean) will not accept more messages and it will throw MaxUnconfirmedMessagesExceededException. The default value can be configure with the 'akka.persistence.at-least-once-delivery.max-unconfirmed-messages' configuration key. This method can be overridden by implementation classes to return non-default values.

Interval between redelivery attempts. The default value can be configure with the 'akka.persistence.at-least-once-delivery.redeliver-interval' configuration key. This method can be overridden by implementation classes to return non-default values.

Maximum number of unconfirmed messages that will be sent at each redelivery burst (burst frequency is half of the redelivery interval). If there's a lot of unconfirmed messages (e.g. if the destination is not available for a long time), this helps prevent an overwhelming amount of messages to be sent at once. The default value can be configure with the 'akka.persistence.at-least-once-delivery.redelivery-burst-limit' configuration key. This method can be overridden by implementation classes to return non-default values.

Number of messages, that have not been confirmed yet.

After this number of delivery attempts a UnconfirmedWarning message will be sent to Self. The count is reset after restart. The default value can be configure with the 'akka.persistence.at-least-once-delivery.warn-after-number-of-unconfirmed-attempts' configuration key. This method can be overridden by implementation classes to return non-default values.