Merge remote-tracking branch 'pwendell/starvation-check'

Also fixed a bug where master was offering executors on dead workers

Conflicts:
	core/src/main/scala/spark/deploy/master/Master.scala

core/src/main/scala/spark/deploy/master/Master.scala

@@ -33,6 +33,8 @@ private[spark] class Master(ip: String, port: Int, webUiPort: Int) extends Actor
   val waitingApps = new ArrayBuffer[ApplicationInfo]
   val completedApps = new ArrayBuffer[ApplicationInfo]
 
+  var firstApp: Option[ApplicationInfo] = None
+
   val masterPublicAddress = {
     val envVar = System.getenv("SPARK_PUBLIC_DNS")
     if (envVar != null) envVar else ip
@@ -167,7 +169,7 @@ private[spark] class Master(ip: String, port: Int, webUiPort: Int) extends Actor
       // Try to spread out each app among all the nodes, until it has all its cores
       for (app <- waitingApps if app.coresLeft > 0) {
         val usableWorkers = workers.toArray.filter(_.state == WorkerState.ALIVE)
-          .filter(canUse(app, _)).sortBy(_.coresFree).reverse
+                                   .filter(canUse(app, _)).sortBy(_.coresFree).reverse
         val numUsable = usableWorkers.length
         val assigned = new Array[Int](numUsable) // Number of cores to give on each node
         var toAssign = math.min(app.coresLeft, usableWorkers.map(_.coresFree).sum)
@@ -190,7 +192,7 @@ private[spark] class Master(ip: String, port: Int, webUiPort: Int) extends Actor
       }
     } else {
       // Pack each app into as few nodes as possible until we've assigned all its cores
-      for (worker <- workers if worker.coresFree > 0) {
+      for (worker <- workers if worker.coresFree > 0 && worker.state == WorkerState.ALIVE) {
         for (app <- waitingApps if app.coresLeft > 0) {
           if (canUse(app, worker)) {
             val coresToUse = math.min(worker.coresFree, app.coresLeft)
@@ -203,6 +205,10 @@ private[spark] class Master(ip: String, port: Int, webUiPort: Int) extends Actor
         }
       }
     }
+    if (workers.toArray.filter(_.state == WorkerState.ALIVE).size > 0 &&
+        firstApp != None && firstApp.get.executors.size == 0) {
+      logWarning("Could not find any machines with enough memory. Ensure that SPARK_WORKER_MEM > SPARK_MEM.")
+    }
   }
 
   def launchExecutor(worker: WorkerInfo, exec: ExecutorInfo, sparkHome: String) {
@@ -245,6 +251,9 @@ private[spark] class Master(ip: String, port: Int, webUiPort: Int) extends Actor
     idToApp(app.id) = app
     actorToApp(driver) = app
     addressToApp(driver.path.address) = app
+    if (firstApp == None) {
+      firstApp = Some(app)
+    }
     return app
   }
 

core/src/main/scala/spark/scheduler/cluster/ClusterScheduler.scala

@@ -11,6 +11,7 @@ import spark.TaskState.TaskState
 import spark.scheduler._
 import java.nio.ByteBuffer
 import java.util.concurrent.atomic.AtomicLong
+import java.util.{TimerTask, Timer}
 
 /**
  * The main TaskScheduler implementation, for running tasks on a cluster. Clients should first call
@@ -22,6 +23,8 @@ private[spark] class ClusterScheduler(val sc: SparkContext)
 
   // How often to check for speculative tasks
   val SPECULATION_INTERVAL = System.getProperty("spark.speculation.interval", "100").toLong
+  // Threshold above which we warn user initial TaskSet may be starved
+  val STARVATION_TIMEOUT = System.getProperty("spark.starvation.timeout", "5000").toLong
 
   val activeTaskSets = new HashMap[String, TaskSetManager]
   var activeTaskSetsQueue = new ArrayBuffer[TaskSetManager]
@@ -30,6 +33,10 @@ private[spark] class ClusterScheduler(val sc: SparkContext)
   val taskIdToExecutorId = new HashMap[Long, String]
   val taskSetTaskIds = new HashMap[String, HashSet[Long]]
 
+  var hasReceivedTask = false
+  var hasLaunchedTask = false
+  val starvationTimer = new Timer(true)
+
   // Incrementing Mesos task IDs
   val nextTaskId = new AtomicLong(0)
 
@@ -94,6 +101,18 @@ private[spark] class ClusterScheduler(val sc: SparkContext)
       activeTaskSets(taskSet.id) = manager
       activeTaskSetsQueue += manager
       taskSetTaskIds(taskSet.id) = new HashSet[Long]()
+
+      if (hasReceivedTask == false) {
+        starvationTimer.scheduleAtFixedRate(new TimerTask() {
+          override def run() {
+            if (!hasLaunchedTask) {
+              logWarning("Initial TaskSet has not accepted any offers. " +
+                "Check the scheduler UI to ensure slaves are registered.")
+            }
+          }
+        }, STARVATION_TIMEOUT, STARVATION_TIMEOUT)
+      }
+      hasReceivedTask = true;
     }
     backend.reviveOffers()
   }
@@ -150,6 +169,7 @@ private[spark] class ClusterScheduler(val sc: SparkContext)
           }
         } while (launchedTask)
       }
+      if (tasks.size > 0) hasLaunchedTask = true
       return tasks
     }
   }
@@ -235,7 +255,7 @@ private[spark] class ClusterScheduler(val sc: SparkContext)
   }
 
   override def defaultParallelism() = backend.defaultParallelism()
-  
+
   // Check for speculatable tasks in all our active jobs.
   def checkSpeculatableTasks() {
     var shouldRevive = false