Re: [akka-user] typed actor on a single thread?

[Konstantinos Kougios]

I wrote a small program to verify it is all ok, sometimes it runs fully and succeeds but most times it get stuck cause it doesn't get all items that it "put" into the map. So what it does is it adds 1 million items into this typed actor map. It then waits till the map's actual size is 1 million ( to make sure all messages were delivered to the map actor). It then gets all items from the map and compares if the key contains the correct value (this always works correctly). Finally it compares the number of gets/checks it did, but this is where it fails, many runs get less items than those were put in the map along with some deadletter logging: package actors import akka.actor.{TypedProps, ActorSystem, TypedActor} import scala.concurrent.ExecutionContext.Implicits.global import java.util.concurrent.atomic.AtomicInteger /**  * @author kkougios  *         Date: 2014/04/08 10:36 AM  */ object Main extends App {     println("Starting up")     val system = ActorSystem("test")     val typed = TypedActor(system)     val service: MapService[Int, String] = typed.typedActorOf(TypedProps[MapServiceImpl[Int, String]])     val Iterations = 1000000     try {         // populate the map using many threads         (1 to Iterations).par.foreach {             i =>                 service(i) = "x" + i         }         // wait till the map is fully populated         while (service.size.get != Iterations) {             println(service.size.get)             Thread.sleep(1000)         }         // now get all items from the map, again using many threads         val l = (1 to Iterations).par.map {             i =>                 service(i).map {                     s => (s, "x" + i)                 }         }.toList         // and verify key<->value pairs match         println("looking for issues")         val checked = new AtomicInteger         l.foreach {             f =>                 f.foreach {                     case (actual, expected) =>                         checked.incrementAndGet()                         if (actual != expected) println("FOUND ISSUE")                 }         }         // also verify we got/checked "Iterations" number of items         println("waiting for checked")         while (checked.get != Iterations) {             println(checked.get)             Thread.sleep(1000)         }     } finally {         typed.poisonPill(service)         println("shutting down")         system.shutdown()     } } running this produces (usually) something like this: Starting up [INFO] [04/08/2014 14:04:16.919] [test-akka.actor.default-dispatcher-11] [akka://test/deadLetters] Message [java.lang.String] from Actor[akka://test/user/$a#1286986617] to Actor[akka://test/deadLetters] was not delivered. [1] dead letters encountered. This logging can be turned off or adjusted with configuration settings 'akka.log-dead-letters' and 'akka.log-dead-letters-during-shutdown'. [INFO] [04/08/2014 14:04:16.919] [test-akka.actor.default-dispatcher-12] [akka://test/deadLetters] Message [java.lang.String] from Actor[akka://test/user/$a#1286986617] to Actor[akka://test/deadLetters] was not delivered. [2] dead letters encountered. This logging can be turned off or adjusted with configuration settings 'akka.log-dead-letters' and 'akka.log-dead-letters-during-shutdown'. [INFO] [04/08/2014 14:04:16.920] [test-akka.actor.default-dispatcher-12] [akka://test/deadLetters] Message [java.lang.String] from Actor[akka://test/user/$a#1286986617] to Actor[akka://test/deadLetters] was not delivered. [3] dead letters encountered. This logging can be turned off or adjusted with configuration settings 'akka.log-dead-letters' and 'akka.log-dead-letters-during-shutdown'. [INFO] [04/08/2014 14:04:16.920] [test-akka.actor.default-dispatcher-12] [akka://test/deadLetters] Message [java.lang.String] from Actor[akka://test/user/$a#1286986617] to Actor[akka://test/deadLetters] was not delivered. [4] dead letters encountered. This logging can be turned off or adjusted with configuration settings 'akka.log-dead-letters' and 'akka.log-dead-letters-during-shutdown'. [INFO] [04/08/2014 14:04:16.920] [test-akka.actor.default-dispatcher-12] [akka://test/deadLetters] Message [java.lang.String] from Actor[akka://test/user/$a#1286986617] to Actor[akka://test/deadLetters] was not delivered. [5] dead letters encountered. This logging can be turned off or adjusted with configuration settings 'akka.log-dead-letters' and 'akka.log-dead-letters-during-shutdown'. [INFO] [04/08/2014 14:04:16.920] [test-akka.actor.default-dispatcher-12] [akka://test/deadLetters] Message [java.lang.String] from Actor[akka://test/user/$a#1286986617] to Actor[akka://test/deadLetters] was not delivered. [6] dead letters encountered. This logging can be turned off or adjusted with configuration settings 'akka.log-dead-letters' and 'akka.log-dead-letters-during-shutdown'. [INFO] [04/08/2014 14:04:16.920] [test-akka.actor.default-dispatcher-10] [akka://test/deadLetters] Message [java.lang.String] from Actor[akka://test/user/$a#1286986617] to Actor[akka://test/deadLetters] was not delivered. [7] dead letters encountered. This logging can be turned off or adjusted with configuration settings 'akka.log-dead-letters' and 'akka.log-dead-letters-during-shutdown'. [INFO] [04/08/2014 14:04:16.920] [test-akka.actor.default-dispatcher-10] [akka://test/deadLetters] Message [java.lang.String] from Actor[akka://test/user/$a#1286986617] to Actor[akka://test/deadLetters] was not delivered. [8] dead letters encountered. This logging can be turned off or adjusted with configuration settings 'akka.log-dead-letters' and 'akka.log-dead-letters-during-shutdown'. [INFO] [04/08/2014 14:04:16.920] [test-akka.actor.default-dispatcher-10] [akka://test/deadLetters] Message [java.lang.String] from Actor[akka://test/user/$a#1286986617] to Actor[akka://test/deadLetters] was not delivered. [9] dead letters encountered. This logging can be turned off or adjusted with configuration settings 'akka.log-dead-letters' and 'akka.log-dead-letters-during-shutdown'. [INFO] [04/08/2014 14:04:16.920] [test-akka.actor.default-dispatcher-10] [akka://test/deadLetters] Message [java.lang.String] from Actor[akka://test/user/$a#1286986617] to Actor[akka://test/deadLetters] was not delivered. [10] dead letters encountered, no more dead letters will be logged. This logging can be turned off or adjusted with configuration settings 'akka.log-dead-letters' and 'akka.log-dead-letters-during-shutdown'. looking for issues waiting for checked 970038 977033 <- this should be 1 million which would allow the program to exit 977033 977033 977033 977033 ... goes on forever Any ideas what might be wrong? Here is the typed actor code: package actors import scala.concurrent.Future /**  * @author kkougios  *         Date: 2014/04/08 10:39 AM  */ trait MapService[K, V] {     def update(k: K, v: V): Unit     def apply(k:K):Future[V]     def size:Option[Int] } class MapServiceImpl[K, V] extends MapService[K, V] {     private val m = collection.mutable.Map.empty[K, V]     override def apply(k: K) = Future.successful(m(k))     override def update(k: K, v: V) = m(k) = v     override def size = Some(m.size) } On 08/04/14 13:26, √iktor Ҡlang wrote: yep On Tue, Apr 8, 2014 at 2:23 PM, Kostas kougios <kostas.koug...@googlemail.com> wrote: Thanks for the replies, so I suppose this typed actor will work just fine. Any execution of the 2 methods will occur at 1 thread at each time and state changes within the actor consists of safe publication. I run it and it looks good. trait MapService[K, V] {     def update(k: K, v: V): Unit     def apply(k:K):Future[V] } class MapServiceImpl[K, V] extends MapService[K, V] {     private val m = collection.mutable.Map.empty[K, V]     override def apply(k: K) = Future.successful(m(k))     override def update(k: K, v: V) = m(k) = v } -- >>>>>>>>>> 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 akka-user+unsubscr...@googlegroups.com. To post to this group, send email to akka-user@googlegroups.com. Visit this group at http://groups.google.com/group/akka-user. 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