! core,akka: separate all akka instrumentation into it's own kamon-akka module, related to #136.

All Akka-related instrumentation and code has been moved to the kamon-akka module,
including the filters for actor, dispatcher and router metrics. Also the following
changes are included:

  - Router Metrics are now working properly, related to #139.
  - Cleanup the log output for this module, related to #142.
  - Some minor cleanups in various tests.

This PR breaks the reporting modules which will need to wait for #141 to be ready to come back
to life.

5 files changed, 0 insertions, 557 deletions

diff --git a/kamon-core/src/main/scala/kamon/instrumentation/akka/ActorCellInstrumentation.scala b/kamon-core/src/main/scala/kamon/instrumentation/akka/ActorCellInstrumentation.scala
deleted file mode 100644
index a340566d..00000000
--- a/kamon-core/src/main/scala/kamon/instrumentation/akka/ActorCellInstrumentation.scala
+++ /dev/null
@@ -1,176 +0,0 @@
-/*
- * =========================================================================================
- * Copyright © 2013-2014 the kamon project <http://kamon.io/>
- *
- * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file
- * except in compliance with the License. You may obtain a copy of the License at
- *
- *   http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software distributed under the
- * License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
- * either express or implied. See the License for the specific language governing permissions
- * and limitations under the License.
- * =========================================================================================
- */
-
-package akka.kamon.instrumentation
-
-import akka.actor._
-import akka.dispatch.{ Envelope, MessageDispatcher }
-import akka.routing.RoutedActorCell
-import kamon.Kamon
-import kamon.metric.ActorMetrics.ActorMetricsRecorder
-import kamon.metric.RouterMetrics.RouterMetricsRecorder
-import kamon.metric.{ ActorMetrics, Metrics, RouterMetrics }
-import kamon.trace._
-import org.aspectj.lang.ProceedingJoinPoint
-import org.aspectj.lang.annotation._
-
-@Aspect
-class ActorCellInstrumentation {
-
-  import ActorCellInstrumentation.PimpedActorCellMetrics
-
-  @Pointcut("execution(akka.actor.ActorCell.new(..)) && this(cell) && args(system, ref, props, dispatcher, parent)")
-  def actorCellCreation(cell: ActorCell, system: ActorSystem, ref: ActorRef, props: Props, dispatcher: MessageDispatcher, parent: ActorRef): Unit = {}
-
-  @After("actorCellCreation(cell, system, ref, props, dispatcher, parent)")
-  def afterCreation(cell: ActorCell, system: ActorSystem, ref: ActorRef, props: Props, dispatcher: MessageDispatcher, parent: ActorRef): Unit = {
-
-    val metricsExtension = Kamon(Metrics)(system)
-    val metricIdentity = ActorMetrics(ref.path.elements.mkString("/"))
-    val cellWithMetrics = cell.asInstanceOf[ActorCellMetrics]
-
-    cellWithMetrics.actorMetricIdentity = metricIdentity
-    cellWithMetrics.actorMetricsRecorder = metricsExtension.register(metricIdentity, ActorMetrics.Factory)
-
-    cellWithMetrics.onRoutedActorCell { routedActorCell ⇒
-      val routerMetricIdentity = RouterMetrics(s"${routedActorCell.asInstanceOf[RoutedActorCell].self.path.elements.mkString("/")}")
-      routedActorCell.routerMetricIdentity = routerMetricIdentity
-      routedActorCell.routerMetricsRecorder = metricsExtension.register(routerMetricIdentity, RouterMetrics.Factory)
-    }
-  }
-
-  @Pointcut("(execution(* akka.actor.ActorCell.invoke(*)) || execution(* akka.routing.RoutedActorCell.sendMessage(*))) && this(cell) && args(envelope)")
-  def invokingActorBehaviourAtActorCell(cell: ActorCell, envelope: Envelope) = {}
-
-  @Around("invokingActorBehaviourAtActorCell(cell, envelope)")
-  def aroundBehaviourInvoke(pjp: ProceedingJoinPoint, cell: ActorCell, envelope: Envelope): Any = {
-    val cellWithMetrics = cell.asInstanceOf[ActorCellMetrics]
-    val timestampBeforeProcessing = System.nanoTime()
-    val contextAndTimestamp = envelope.asInstanceOf[TimestampedTraceContextAware]
-
-    try {
-      TraceRecorder.withInlineTraceContextReplacement(contextAndTimestamp.traceContext) {
-        pjp.proceed()
-      }
-    } finally {
-      cellWithMetrics.actorMetricsRecorder.map {
-        am ⇒
-          val processingTime = System.nanoTime() - timestampBeforeProcessing
-          val timeInMailbox = timestampBeforeProcessing - contextAndTimestamp.captureNanoTime
-
-          am.processingTime.record(processingTime)
-          am.timeInMailbox.record(timeInMailbox)
-          am.mailboxSize.decrement()
-
-          (processingTime, timeInMailbox)
-      } map {
-        case (processingTime, timeInMailbox) ⇒
-          cellWithMetrics.onRoutedActorCell { routedActorCell ⇒
-            routedActorCell.routerMetricsRecorder.map {
-              rm ⇒
-                rm.processingTime.record(processingTime)
-                rm.timeInMailbox.record(timeInMailbox)
-            }
-          }
-      }
-    }
-  }
-
-  @Pointcut("execution(* akka.actor.ActorCell.sendMessage(*)) && this(cell)")
-  def sendingMessageToActorCell(cell: ActorCell): Unit = {}
-
-  @After("sendingMessageToActorCell(cell)")
-  def afterSendMessageToActorCell(cell: ActorCell): Unit = {
-    val cellWithMetrics = cell.asInstanceOf[ActorCellMetrics]
-    cellWithMetrics.actorMetricsRecorder.map(am ⇒ am.mailboxSize.increment())
-  }
-
-  @Pointcut("execution(* akka.actor.ActorCell.stop()) && this(cell)")
-  def actorStop(cell: ActorCell): Unit = {}
-
-  @After("actorStop(cell)")
-  def afterStop(cell: ActorCell): Unit = {
-    val cellWithMetrics = cell.asInstanceOf[ActorCellMetrics]
-
-    cellWithMetrics.actorMetricsRecorder.map { p ⇒
-      Kamon(Metrics)(cell.system).unregister(cellWithMetrics.actorMetricIdentity)
-    }
-
-    cellWithMetrics.onRoutedActorCell { routedActorCell ⇒
-      routedActorCell.routerMetricsRecorder.map { rm ⇒
-        Kamon(Metrics)(cell.system).unregister(cellWithMetrics.routerMetricIdentity)
-      }
-    }
-  }
-
-  @Pointcut("execution(* akka.actor.ActorCell.handleInvokeFailure(..)) && this(cell)")
-  def actorInvokeFailure(cell: ActorCell): Unit = {}
-
-  @Before("actorInvokeFailure(cell)")
-  def beforeInvokeFailure(cell: ActorCell): Unit = {
-    val cellWithMetrics = cell.asInstanceOf[ActorCellMetrics]
-
-    cellWithMetrics.actorMetricsRecorder.map {
-      am ⇒ am.errors.increment()
-    }
-
-    cellWithMetrics.onRoutedActorCell { routedActorCell ⇒
-      routedActorCell.routerMetricsRecorder.map {
-        rm ⇒ rm.errors.increment()
-      }
-    }
-  }
-
-}
-
-trait ActorCellMetrics {
-  var actorMetricIdentity: ActorMetrics = _
-  var routerMetricIdentity: RouterMetrics = _
-  var actorMetricsRecorder: Option[ActorMetricsRecorder] = _
-  var routerMetricsRecorder: Option[RouterMetricsRecorder] = _
-}
-
-@Aspect
-class ActorCellMetricsIntoActorCellMixin {
-
-  @DeclareMixin("akka.actor.ActorCell")
-  def mixinActorCellMetricsToActorCell: ActorCellMetrics = new ActorCellMetrics {}
-}
-
-@Aspect
-class TraceContextIntoEnvelopeMixin {
-
-  @DeclareMixin("akka.dispatch.Envelope")
-  def mixinTraceContextAwareToEnvelope: TimestampedTraceContextAware = TimestampedTraceContextAware.default
-
-  @Pointcut("execution(akka.dispatch.Envelope.new(..)) && this(ctx)")
-  def envelopeCreation(ctx: TimestampedTraceContextAware): Unit = {}
-
-  @After("envelopeCreation(ctx)")
-  def afterEnvelopeCreation(ctx: TimestampedTraceContextAware): Unit = {
-    // Necessary to force the initialization of ContextAware at the moment of creation.
-    ctx.traceContext
-  }
-}
-
-object ActorCellInstrumentation {
-  implicit class PimpedActorCellMetrics(cell: ActorCellMetrics) {
-    def onRoutedActorCell(block: ActorCellMetrics ⇒ Unit) = cell match {
-      case routedActorCell: RoutedActorCell ⇒ block(cell)
-      case everythingElse                   ⇒
-    }
-  }
-}
\ No newline at end of file
diff --git a/kamon-core/src/main/scala/kamon/instrumentation/akka/ActorLoggingInstrumentation.scala b/kamon-core/src/main/scala/kamon/instrumentation/akka/ActorLoggingInstrumentation.scala
deleted file mode 100644
index e0e5d316..00000000
--- a/kamon-core/src/main/scala/kamon/instrumentation/akka/ActorLoggingInstrumentation.scala
+++ /dev/null
@@ -1,50 +0,0 @@
-/*
- * =========================================================================================
- * Copyright © 2013-2014 the kamon project <http://kamon.io/>
- *
- * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file
- * except in compliance with the License. You may obtain a copy of the License at
- *
- *   http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software distributed under the
- * License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
- * either express or implied. See the License for the specific language governing permissions
- * and limitations under the License.
- * =========================================================================================
- */
-
-package akka.kamon.instrumentation
-
-import kamon.trace.logging.MdcKeysSupport
-import kamon.trace.{ TraceContextAware, TraceRecorder }
-import org.aspectj.lang.ProceedingJoinPoint
-import org.aspectj.lang.annotation._
-
-@Aspect
-class ActorLoggingInstrumentation extends MdcKeysSupport {
-
-  @DeclareMixin("akka.event.Logging.LogEvent+")
-  def mixinTraceContextAwareToLogEvent: TraceContextAware = TraceContextAware.default
-
-  @Pointcut("execution(akka.event.Logging.LogEvent+.new(..)) && this(event)")
-  def logEventCreation(event: TraceContextAware): Unit = {}
-
-  @After("logEventCreation(event)")
-  def captureTraceContext(event: TraceContextAware): Unit = {
-    // Force initialization of TraceContextAware
-    event.traceContext
-  }
-
-  @Pointcut("execution(* akka.event.slf4j.Slf4jLogger.withMdc(..)) && args(logSource, logEvent, logStatement)")
-  def withMdcInvocation(logSource: String, logEvent: TraceContextAware, logStatement: () ⇒ _): Unit = {}
-
-  @Around("withMdcInvocation(logSource, logEvent, logStatement)")
-  def aroundWithMdcInvocation(pjp: ProceedingJoinPoint, logSource: String, logEvent: TraceContextAware, logStatement: () ⇒ _): Unit = {
-    TraceRecorder.withInlineTraceContextReplacement(logEvent.traceContext) {
-      withMdc {
-        pjp.proceed()
-      }
-    }
-  }
-}
diff --git a/kamon-core/src/main/scala/kamon/instrumentation/akka/ActorSystemMessageInstrumentation.scala b/kamon-core/src/main/scala/kamon/instrumentation/akka/ActorSystemMessageInstrumentation.scala
deleted file mode 100644
index 48016876..00000000
--- a/kamon-core/src/main/scala/kamon/instrumentation/akka/ActorSystemMessageInstrumentation.scala
+++ /dev/null
@@ -1,80 +0,0 @@
-/*
- * =========================================================================================
- * Copyright © 2013-2014 the kamon project <http://kamon.io/>
- *
- * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file
- * except in compliance with the License. You may obtain a copy of the License at
- *
- *   http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software distributed under the
- * License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
- * either express or implied. See the License for the specific language governing permissions
- * and limitations under the License.
- * =========================================================================================
- */
-
-package akka.kamon.instrumentation
-
-import akka.dispatch.sysmsg.EarliestFirstSystemMessageList
-import kamon.trace.{ TraceContextAware, TraceRecorder }
-import org.aspectj.lang.ProceedingJoinPoint
-import org.aspectj.lang.annotation._
-
-@Aspect
-class ActorSystemMessageInstrumentation {
-
-  @Pointcut("execution(* akka.actor.ActorCell.invokeAll$1(..)) && args(messages, *)")
-  def systemMessageProcessing(messages: EarliestFirstSystemMessageList): Unit = {}
-
-  @Around("systemMessageProcessing(messages)")
-  def aroundSystemMessageInvoke(pjp: ProceedingJoinPoint, messages: EarliestFirstSystemMessageList): Any = {
-    if (messages.nonEmpty) {
-      val ctx = messages.head.asInstanceOf[TraceContextAware].traceContext
-      TraceRecorder.withInlineTraceContextReplacement(ctx)(pjp.proceed())
-
-    } else pjp.proceed()
-  }
-}
-
-@Aspect
-class TraceContextIntoSystemMessageMixin {
-
-  @DeclareMixin("akka.dispatch.sysmsg.SystemMessage+")
-  def mixinTraceContextAwareToSystemMessage: TraceContextAware = TraceContextAware.default
-
-  @Pointcut("execution(akka.dispatch.sysmsg.SystemMessage+.new(..)) && this(ctx)")
-  def envelopeCreation(ctx: TraceContextAware): Unit = {}
-
-  @After("envelopeCreation(ctx)")
-  def afterEnvelopeCreation(ctx: TraceContextAware): Unit = {
-    // Necessary to force the initialization of ContextAware at the moment of creation.
-    ctx.traceContext
-  }
-}
-
-@Aspect
-class TraceContextIntoRepointableActorRefMixin {
-
-  @DeclareMixin("akka.actor.RepointableActorRef")
-  def mixinTraceContextAwareToRepointableActorRef: TraceContextAware = TraceContextAware.default
-
-  @Pointcut("execution(akka.actor.RepointableActorRef.new(..)) && this(ctx)")
-  def envelopeCreation(ctx: TraceContextAware): Unit = {}
-
-  @After("envelopeCreation(ctx)")
-  def afterEnvelopeCreation(ctx: TraceContextAware): Unit = {
-    // Necessary to force the initialization of ContextAware at the moment of creation.
-    ctx.traceContext
-  }
-
-  @Pointcut("execution(* akka.actor.RepointableActorRef.point(..)) && this(repointableActorRef)")
-  def repointableActorRefCreation(repointableActorRef: TraceContextAware): Unit = {}
-
-  @Around("repointableActorRefCreation(repointableActorRef)")
-  def afterRepointableActorRefCreation(pjp: ProceedingJoinPoint, repointableActorRef: TraceContextAware): Any = {
-    TraceRecorder.withInlineTraceContextReplacement(repointableActorRef.traceContext) {
-      pjp.proceed()
-    }
-  }
-}
\ No newline at end of file
diff --git a/kamon-core/src/main/scala/kamon/instrumentation/akka/AskPatternInstrumentation.scala b/kamon-core/src/main/scala/kamon/instrumentation/akka/AskPatternInstrumentation.scala
deleted file mode 100644
index 5b4fbbc8..00000000
--- a/kamon-core/src/main/scala/kamon/instrumentation/akka/AskPatternInstrumentation.scala
+++ /dev/null
@@ -1,88 +0,0 @@
-/*
- * =========================================================================================
- * Copyright © 2013-2014 the kamon project <http://kamon.io/>
- *
- * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file
- * except in compliance with the License. You may obtain a copy of the License at
- *
- *   http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software distributed under the
- * License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
- * either express or implied. See the License for the specific language governing permissions
- * and limitations under the License.
- * =========================================================================================
- */
-
-package akka.kamon.instrumentation
-
-import kamon.Kamon
-import kamon.extension.akka.Akka
-import kamon.trace.{ TraceContext, EmptyTraceContext, TraceContextAware }
-import akka.actor.{ ActorSystem, ActorRef }
-import akka.event.Logging.Warning
-import akka.pattern.AskTimeoutException
-import org.aspectj.lang.ProceedingJoinPoint
-import org.aspectj.lang.annotation._
-import org.aspectj.lang.reflect.SourceLocation
-import scala.concurrent.Future
-import scala.compat.Platform.EOL
-
-@Aspect
-class AskPatternInstrumentation {
-
-  import AskPatternInstrumentation._
-
-  @DeclareMixin("akka.pattern.AskableActorRef$")
-  def mixinContextAwareToAskableActorRef: TraceContextAware = TraceContextAware.default
-
-  @Pointcut("call(* akka.pattern.AskableActorRef$.$qmark$extension(..)) && target(ctx) && args(actor, *, *)")
-  def askableActorRefAsk(ctx: TraceContextAware, actor: ActorRef): Unit = {}
-
-  @Around("askableActorRefAsk(ctx, actor)")
-  def hookAskTimeoutWarning(pjp: ProceedingJoinPoint, ctx: TraceContextAware, actor: ActorRef): AnyRef = ctx.traceContext match {
-    case EmptyTraceContext ⇒ pjp.proceed()
-    case ctx: TraceContext ⇒
-      implicit val system = ctx.system
-      val akkaExtension = Kamon(Akka)(system)
-
-      val future = pjp.proceed().asInstanceOf[Future[AnyRef]]
-
-      val handler = akkaExtension.askPatternTimeoutWarning match {
-        case "off"         ⇒ None
-        case "lightweight" ⇒ Some(errorHandler(callInfo = Some(CallInfo(s"${actor.path.name} ?", pjp.getSourceLocation))))
-        case "heavyweight" ⇒ Some(errorHandler(stack = Some(new StackTraceCaptureException)))
-      }
-
-      handler.map(future.onFailure(_)(akkaExtension.dispatcher))
-      future
-  }
-
-  def errorHandler(callInfo: Option[CallInfo] = None, stack: Option[StackTraceCaptureException] = None)(implicit system: ActorSystem): ErrorHandler = {
-    case e: AskTimeoutException ⇒
-      val message = {
-        if (stack.isDefined) stack.map(s ⇒ s.getStackTrace.drop(3).mkString("", EOL, EOL))
-        else callInfo.map(_.message)
-      }
-      publish(message)
-  }
-
-  def publish(message: Option[String])(implicit system: ActorSystem) = message map { msg ⇒
-    system.eventStream.publish(Warning("AskPatternTracing", classOf[AskPatternInstrumentation],
-      s"Timeout triggered for ask pattern registered at: $msg"))
-  }
-}
-
-object AskPatternInstrumentation {
-  type ErrorHandler = PartialFunction[Throwable, Unit]
-
-  class StackTraceCaptureException extends Throwable
-
-  case class CallInfo(name: String, sourceLocation: SourceLocation) {
-    def message: String = {
-      def locationInfo: String = Option(sourceLocation).map(location ⇒ s"${location.getFileName}:${location.getLine}").getOrElse("<unknown position>")
-      def line: String = s"$name @ $locationInfo"
-      s"$line"
-    }
-  }
-}
\ No newline at end of file
diff --git a/kamon-core/src/main/scala/kamon/instrumentation/akka/DispatcherInstrumentation.scala b/kamon-core/src/main/scala/kamon/instrumentation/akka/DispatcherInstrumentation.scala
deleted file mode 100644
index 4b1bbc4d..00000000
--- a/kamon-core/src/main/scala/kamon/instrumentation/akka/DispatcherInstrumentation.scala
+++ /dev/null
@@ -1,163 +0,0 @@
-/*
- * =========================================================================================
- * Copyright © 2013-2014 the kamon project <http://kamon.io/>
- *
- * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file
- * except in compliance with the License. You may obtain a copy of the License at
- *
- *   http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software distributed under the
- * License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
- * either express or implied. See the License for the specific language governing permissions
- * and limitations under the License.
- * =========================================================================================
- */
-
-package akka.kamon.instrumentation
-
-import java.lang.reflect.Method
-import java.util.concurrent.ThreadPoolExecutor
-
-import akka.actor.{ ActorSystemImpl, Cancellable }
-import akka.dispatch.{ Dispatcher, Dispatchers, ExecutorServiceDelegate, MessageDispatcher }
-import akka.kamon.instrumentation.DispatcherMetricsCollector.DispatcherMetricsMeasurement
-import kamon.Kamon
-import kamon.metric.DispatcherMetrics.DispatcherMetricRecorder
-import kamon.metric.{ DispatcherMetrics, Metrics }
-import org.aspectj.lang.annotation._
-
-import scala.concurrent.forkjoin.ForkJoinPool
-
-@Aspect
-class DispatcherInstrumentation {
-
-  @Pointcut("execution(akka.dispatch.Dispatchers.new(..)) && this(dispatchers) && cflow(execution(akka.actor.ActorSystemImpl.new(..)) && this(system))")
-  def onActorSystemStartup(dispatchers: Dispatchers, system: ActorSystemImpl) = {}
-
-  @Before("onActorSystemStartup(dispatchers, system)")
-  def beforeActorSystemStartup(dispatchers: Dispatchers, system: ActorSystemImpl): Unit = {
-    val currentDispatchers = dispatchers.asInstanceOf[DispatchersWithActorSystem]
-    currentDispatchers.actorSystem = system
-  }
-
-  @Pointcut("execution(* akka.dispatch.Dispatchers.lookup(..)) && this(dispatchers)")
-  def onDispatchersLookup(dispatchers: Dispatchers) = {}
-
-  @AfterReturning(pointcut = "onDispatchersLookup(dispatchers)", returning = "dispatcher")
-  def afterReturningLookup(dispatchers: Dispatchers, dispatcher: Dispatcher): Unit = {
-    val dispatchersWithActorSystem = dispatchers.asInstanceOf[DispatchersWithActorSystem]
-    val dispatcherWithMetrics = dispatcher.asInstanceOf[DispatcherMetricCollectionInfo]
-
-    dispatcherWithMetrics.actorSystem = dispatchersWithActorSystem.actorSystem
-  }
-
-  @Pointcut("call(* akka.dispatch.ExecutorServiceFactory.createExecutorService(..))")
-  def onCreateExecutorService(): Unit = {}
-
-  @Pointcut("cflow((execution(* akka.dispatch.MessageDispatcher.registerForExecution(..)) || execution(* akka.dispatch.MessageDispatcher.executeTask(..))) && this(dispatcher))")
-  def onCflowMessageDispatcher(dispatcher: Dispatcher): Unit = {}
-
-  @Pointcut("onCreateExecutorService() && onCflowMessageDispatcher(dispatcher)")
-  def onDispatcherStartup(dispatcher: Dispatcher): Unit = {}
-
-  @After("onDispatcherStartup(dispatcher)")
-  def afterDispatcherStartup(dispatcher: MessageDispatcher): Unit = {
-
-    val dispatcherWithMetrics = dispatcher.asInstanceOf[DispatcherMetricCollectionInfo]
-    val metricsExtension = Kamon(Metrics)(dispatcherWithMetrics.actorSystem)
-    val metricIdentity = DispatcherMetrics(dispatcher.id)
-
-    dispatcherWithMetrics.metricIdentity = metricIdentity
-    dispatcherWithMetrics.dispatcherMetricsRecorder = metricsExtension.register(metricIdentity, DispatcherMetrics.Factory)
-
-    if (dispatcherWithMetrics.dispatcherMetricsRecorder.isDefined) {
-      dispatcherWithMetrics.dispatcherCollectorCancellable = metricsExtension.scheduleGaugeRecorder {
-        dispatcherWithMetrics.dispatcherMetricsRecorder.map {
-          dm ⇒
-            val DispatcherMetricsMeasurement(maximumPoolSize, runningThreadCount, queueTaskCount, poolSize) =
-              DispatcherMetricsCollector.collect(dispatcher)
-
-            dm.maximumPoolSize.record(maximumPoolSize)
-            dm.runningThreadCount.record(runningThreadCount)
-            dm.queueTaskCount.record(queueTaskCount)
-            dm.poolSize.record(poolSize)
-        }
-      }
-    }
-  }
-
-  @Pointcut("execution(* akka.dispatch.MessageDispatcher.shutdown(..)) && this(dispatcher)")
-  def onDispatcherShutdown(dispatcher: MessageDispatcher): Unit = {}
-
-  @After("onDispatcherShutdown(dispatcher)")
-  def afterDispatcherShutdown(dispatcher: MessageDispatcher): Unit = {
-    val dispatcherWithMetrics = dispatcher.asInstanceOf[DispatcherMetricCollectionInfo]
-
-    dispatcherWithMetrics.dispatcherMetricsRecorder.map {
-      dispatcher ⇒
-        dispatcherWithMetrics.dispatcherCollectorCancellable.cancel()
-        Kamon(Metrics)(dispatcherWithMetrics.actorSystem).unregister(dispatcherWithMetrics.metricIdentity)
-    }
-  }
-}
-
-@Aspect
-class DispatcherMetricCollectionInfoIntoDispatcherMixin {
-
-  @DeclareMixin("akka.dispatch.MessageDispatcher")
-  def mixinDispatcherMetricsToMessageDispatcher: DispatcherMetricCollectionInfo = new DispatcherMetricCollectionInfo {}
-
-  @DeclareMixin("akka.dispatch.Dispatchers")
-  def mixinDispatchersToDispatchersWithActorSystem: DispatchersWithActorSystem = new DispatchersWithActorSystem {}
-}
-
-trait DispatcherMetricCollectionInfo {
-  var metricIdentity: DispatcherMetrics = _
-  var dispatcherMetricsRecorder: Option[DispatcherMetricRecorder] = _
-  var dispatcherCollectorCancellable: Cancellable = _
-  var actorSystem: ActorSystemImpl = _
-}
-
-trait DispatchersWithActorSystem {
-  var actorSystem: ActorSystemImpl = _
-}
-
-object DispatcherMetricsCollector {
-
-  case class DispatcherMetricsMeasurement(maximumPoolSize: Long, runningThreadCount: Long, queueTaskCount: Long, poolSize: Long)
-
-  private def collectForkJoinMetrics(pool: ForkJoinPool): DispatcherMetricsMeasurement = {
-    DispatcherMetricsMeasurement(pool.getParallelism, pool.getActiveThreadCount,
-      (pool.getQueuedTaskCount + pool.getQueuedSubmissionCount), pool.getPoolSize)
-  }
-
-  private def collectExecutorMetrics(pool: ThreadPoolExecutor): DispatcherMetricsMeasurement = {
-    DispatcherMetricsMeasurement(pool.getMaximumPoolSize, pool.getActiveCount, pool.getQueue.size(), pool.getPoolSize)
-  }
-
-  private val executorServiceMethod: Method = {
-    // executorService is protected
-    val method = classOf[Dispatcher].getDeclaredMethod("executorService")
-    method.setAccessible(true)
-    method
-  }
-
-  def collect(dispatcher: MessageDispatcher): DispatcherMetricsMeasurement = {
-    dispatcher match {
-      case x: Dispatcher ⇒ {
-        val executor = executorServiceMethod.invoke(x) match {
-          case delegate: ExecutorServiceDelegate ⇒ delegate.executor
-          case other                             ⇒ other
-        }
-
-        executor match {
-          case fjp: ForkJoinPool       ⇒ collectForkJoinMetrics(fjp)
-          case tpe: ThreadPoolExecutor ⇒ collectExecutorMetrics(tpe)
-          case anything                ⇒ DispatcherMetricsMeasurement(0L, 0L, 0L, 0L)
-        }
-      }
-      case _ ⇒ new DispatcherMetricsMeasurement(0L, 0L, 0L, 0L)
-    }
-  }
-}