taskInfo tracks if a task is run on a preferred host

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

@@ -11,7 +11,8 @@ class TaskInfo(
     val index: Int,
     val launchTime: Long,
     val executorId: String,
-    val host: String) {
+    val host: String,
+    val preferred: Boolean) {
   var finishTime: Long = 0
   var failed = false
 

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

@@ -208,7 +208,7 @@ private[spark] class TaskSetManager(sched: ClusterScheduler, val taskSet: TaskSe
             taskSet.id, index, taskId, execId, host, prefStr))
           // Do various bookkeeping
           copiesRunning(index) += 1
-          val info = new TaskInfo(taskId, index, time, execId, host)
+          val info = new TaskInfo(taskId, index, time, execId, host, preferred)
           taskInfos(taskId) = info
           taskAttempts(index) = info :: taskAttempts(index)
           if (preferred) {

core/src/main/scala/spark/scheduler/local/LocalScheduler.scala

@@ -53,7 +53,7 @@ private[spark] class LocalScheduler(threads: Int, maxFailures: Int, sc: SparkCon
 
     def runTask(task: Task[_], idInJob: Int, attemptId: Int) {
       logInfo("Running " + task)
-      val info = new TaskInfo(attemptId, idInJob, System.currentTimeMillis(), "local", "local")
+      val info = new TaskInfo(attemptId, idInJob, System.currentTimeMillis(), "local", "local", true)
       // Set the Spark execution environment for the worker thread
       SparkEnv.set(env)
       try {