#1417 - Added a test to attempt to statistically verify memory consistency for actors

akka-actor-tests/src/test/scala/akka/actor/ConsistencySpec.scala

@@ -0,0 +1,49 @@
+package akka.actor
+
+import akka.testkit.AkkaSpec
+import akka.dispatch.UnboundedMailbox
+import akka.util.duration._
+
+object ConsistencySpec {
+  class CacheMisaligned(var value: Long, var padding1: Long, var padding2: Long, var padding3: Int) //Vars, no final fences
+
+  class ConsistencyCheckingActor extends Actor {
+    var left = new CacheMisaligned(42, 0, 0, 0) //var
+    var right = new CacheMisaligned(0, 0, 0, 0) //var
+    def receive = {
+      case "check" ⇒
+        var shouldBeFortyTwo = left.value + right.value
+        if (shouldBeFortyTwo != 42)
+          sender ! "Test failed"
+        else {
+          left.value += 1
+          right.value -= 1
+        }
+      case "done" ⇒ sender ! "done"; self.stop()
+    }
+  }
+}
+
+class ConsistencySpec extends AkkaSpec {
+  import ConsistencySpec._
+  "The Akka actor model implementation" must {
+    "provide memory consistency" in {
+      val dispatcher = system
+        .dispatcherFactory
+        .newDispatcher("consistency-dispatcher", 1, UnboundedMailbox())
+        .withNewThreadPoolWithArrayBlockingQueueWithCapacityAndFairness(1000, true)
+        .setCorePoolSize(10)
+        .setMaxPoolSize(10)
+        .setKeepAliveTimeInMillis(1)
+        .setAllowCoreThreadTimeout(true)
+        .build
+
+      val props = Props[ConsistencyCheckingActor].withDispatcher(dispatcher)
+      val actors = Vector.fill(3)(system.actorOf(props))
+      for (i ← 1 to 1000000) actors(i % actors.size).tell("check", testActor)
+      for (a ← actors) a.tell("done", testActor)
+
+      for (a ← actors) expectMsg(5 minutes, "done")
+    }
+  }
+}