Java Akka - 从父上下文向子动作广播消息

Question

ActorSelection selection =   context.actorSelection( "/user/ParentActor/*");
selection.tell(msg,null);

Assumming the parent actor context presented here in the example has more than 1 actor.

Does the above tell statement send message to all child actors sequentially or parallely.That is whether the tell statement behave like a broadcastor or internally an iteration is performed to send message to each actor in the selection

Answer 1

Looking here (which is the method called by the tell) it seems to use an iterator, so I'd say sequential.

Nonetheless, it's a quite lightweight operation, so you shouldn't worry too much about it.

Answer 2

If you're concerned about performance, it might be better to keep track of the actors, or to use an event bus. In an event bus you can have the actors subscribe to a topic and then you broadcast the message through the event bus. http://doc.akka.io/docs/akka/snapshot/java/event-bus.html

You could also use a router to broadcast to all children. http://doc.akka.io/docs/akka/snapshot/scala/routing.html