Note that you must only use getSender when processing a message (i.e. onReceive call). It must not be accessed from other asynchronous callbacks running in other threads, such as futures. Note that the creator function or constructor of a child actor is running in a different thread so you must first assign getSender() to a stable variable.
/Patrik On Wed, Oct 14, 2015 at 1:43 AM, ryan walsh <[email protected]> wrote: > I have an odd bug in production that I can't figure out and am wondering > if it sounds familiar to anyone. > > > Background: > I have 3 components: UI, CommandService, and OptimizerAdapter. > > The seed nodes are as follows: > > UI list: CommandService nodes, UI nodes > OptimizerAdapter list: CommandService nodes, OptimizerAdapter nodes > CommandService list: CommandService nodes, OptimizerAdapter nodes, UI nodes > > We do this to make the Command Service the "candle stick" of sorts that > ties the cluster together. > > Physically, the OptimizerAdapter and CommandService are colocated, while > the UI lives on a different set of VMs > > Messaging flow: > > > 1. User inputs a request to the UI. UI creates an Actor to handle the > specific request > 2. UI sends the request on the pub sub mediator with the actor created > in step 1 as the sender > 3. OptimizerAdapter is listening on the mediator topic and picks up > the request > 4. OptimizerAdapter creates an Actor to handle this specific request > so it is free to listen for more requests from the mediator > 5. The Actor from Step 4 sends some commands to the CommandService, > and waits until it hears back from it to move to step 6 > 6. The Actor from Step 4 then kicks off an optimization run (via a > message published to JMS) > 7. The Actor from Step 4 listens on a JMS topic and relays status > updates to the original sender from step 2 > 1. This sender was passed in at actor creation > 8. The UI sender updates the UI as necessary as it receives status > updates from step 7 > 9. When the optimization run is complete, the actor from step 4 fires > off a COMPLETE message to the UI and kills himself > 10. When the UI receives a complete or fail, it kills its handler actor > > This flow seems to work fine about half the time. If I kick off 2 > concurrent requests to the UI, we seem ok. If I do more than that, Step 8 > never happens. My OptimizerAdapter is able to receive the request from the > UI, but the UI never receives any status updates in its handler despite my > logs showing that the OptimizerAdapter is calling .tell on the ActorRef > passed in by getSender(). > > Following the Actor per request model seemed appropriate here, but I am > unsure why the responses to the UI seem to never happen. I am not seeing > any deadletters logs or anything. Just a log indicating that I called > originalSender.tell and nothing on the other end (UI logs for the handler) > > > > -- > >>>>>>>>>> Read the docs: http://akka.io/docs/ > >>>>>>>>>> Check the FAQ: > http://doc.akka.io/docs/akka/current/additional/faq.html > >>>>>>>>>> Search the archives: https://groups.google.com/group/akka-user > --- > You received this message because you are subscribed to the Google Groups > "Akka User List" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To post to this group, send email to [email protected]. > Visit this group at http://groups.google.com/group/akka-user. > For more options, visit https://groups.google.com/d/optout. > -- Patrik Nordwall Typesafe <http://typesafe.com/> - Reactive apps on the JVM Twitter: @patriknw -- >>>>>>>>>> Read the docs: http://akka.io/docs/ >>>>>>>>>> Check the FAQ: >>>>>>>>>> http://doc.akka.io/docs/akka/current/additional/faq.html >>>>>>>>>> Search the archives: https://groups.google.com/group/akka-user --- You received this message because you are subscribed to the Google Groups "Akka User List" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at http://groups.google.com/group/akka-user. For more options, visit https://groups.google.com/d/optout.
