Harden ResizerSpec a bit more. See #2822

akka-actor-tests/src/test/scala/akka/routing/ResizerSpec.scala

@@ -176,13 +176,13 @@ class ResizerSpec extends AkkaSpec(ResizerSpec.config) with DefaultTimeout with
     "backoff" in within(10 seconds) {
 
       val resizer = DefaultResizer(
-        lowerBound = 1,
+        lowerBound = 2,
         upperBound = 5,
         rampupRate = 1.0,
         backoffRate = 1.0,
         backoffThreshold = 0.40,
         pressureThreshold = 1,
-        messagesPerResize = 1)
+        messagesPerResize = 2)
 
       val router = system.actorOf(Props(new Actor {
         def receive = {
@@ -192,19 +192,20 @@ class ResizerSpec extends AkkaSpec(ResizerSpec.config) with DefaultTimeout with
       }).withRouter(RoundRobinRouter(resizer = Some(resizer))))
 
       // put some pressure on the router
-      for (m ← 0 to 5) {
-        router ! 100
+      for (m ← 0 until 15) {
+        router ! 150
         Thread.sleep((20 millis).dilated.toMillis)
       }
 
       val z = routeeSize(router)
-      z must be >= (2)
+      z must be > (2)
 
       Thread.sleep((300 millis).dilated.toMillis)
 
       // let it cool down
       awaitCond({
         router ! 0 // trigger resize
+        Thread.sleep((20 millis).dilated.toMillis)
         routeeSize(router) < z
       }, interval = 500.millis.dilated)