helena

class ClusterMetricsElasticScaleListener extends Actor with ActorLogging {
  val selfAddress = Cluster(context.system).selfAddress

  override def preStart(): Unit =
    Cluster(context.system).subscribe(self, classOf[ClusterMetricsChanged])

  override def postStop(): Unit =
    Cluster(context.system).unsubscribe(self)

  def receive = {

helena

akka {
  cluster {
    metrics {
      # Enable or disable metrics collector for load-balancing nodes.
      enabled = on
 
      # FQCN of the metrics collector implementation. 
      # It must implement akka.cluster.cluster.MetricsCollector and
      # have public constructor with akka.actor.ActorSystem parameter.
      # The default SigarMetricsCollector uses JMX and Hyperic SIGAR, 

helena

java -classpath sigar-1.6.5.132.jar

helena

"org.hyperic" % "sigar" % "1.6.4"

helena

// Start by adding these
import scala.util.{ Try, Success, Failure }

/**
 * Sample runs code that raises the exception:
 * java.lang.ArithmeticException: / by zero
 */ 
object Sample {

  def main(args: Array[String]): Unit = {

helena

package foo

import akka.actor.{Actor, ActorSystem} 

/** 
 * Implement a simple application in Akka and Scala:
 * 
 * Don't worry about spending too much time on it, or
 * everything being perfect if you are not yet familiar...
 * I just want to see how you think and what you might know,

helena

package foo

import akka.actor.{Actor, ActorSystem}
import akka.util.Timeout

/** 
 * Implement a simple application in Akka and Scala:
 * Don't worry about spending too much time on it, or
 * everything being perfect if you are not yet familiar...
 * I just want to see how you think on something simple,

helena

# Here are some of the more interesting configurable cluster properties
# that enable you to maintain health of your system

# Note: The provider to use
akka.actor.provider = akka.cluster.ClusterActorRefProvider

akka.cluster {
  
  # how often metrics will be sampled on each node
  metrics.metrics-interval = 3s

helena

# Here are some of the more interesting configurable cluster properties 
# that enable you to maintain health of your system

# Note: The provider to use
akka.actor.provider = akka.cluster.ClusterActorRefProvider

akka.cluster {
  
  # if after this duration no heartbeat has been received, you have a problem
  failure-detector.acceptable-heartbeat-pause = 5s

helena

val system = ActorSystem("ClusterSystem")

system.actorOf(Props(new Actor with ActorLogging { 
    
  val cluster = Cluster(context.system)
  
  override def preStart(): Unit = 
    cluster.subscribe(self, classOf[ClusterDomainEvent])
  
  def receive = {