Fixed performance issues more

Author: sarutak

core/src/main/resources/org/apache/spark/ui/static/timeline-view.js

@@ -154,11 +154,7 @@ function drawTaskAssignmentTimeline(groupArray, eventObjArray, minLaunchTime, zo
   taskTimeline.setOptions(options);
   taskTimeline.setGroups(groups);
   taskTimeline.setItems(items);
-  var curEnd = taskTimeline.getWindow()["end"].getTime();
-  if (curEnd - minLaunchTime > zoomMax) {
-    curEnd = minLaunchTime + zoomMax;
-  }
-  taskTimeline.setWindow(minLaunchTime, curEnd);
+
   taskTimeline.on("rangechange", function(prop) {
     if (currentDisplayedTooltip !== null) {
       $(currentDisplayedTooltip).tooltip("hide");

core/src/main/scala/org/apache/spark/ui/jobs/StagePage.scala

@@ -646,20 +646,7 @@ private[ui] class StagePage(parent: StagesTab) extends WebUIPage("stage") {
           """
     }.mkString("[", ",", "]")
 
-    var maxWindowInSec = ((maxFinishTime - minLaunchTime) / 1000.0).round
-    if (maxWindowInSec <= 0) maxWindowInSec = 1
-    val tasksPerSecond = numEffectiveTasks / maxWindowInSec
-    var maxZoom = {
-      if (tasksPerSecond > 100) {
-        1000L / (tasksPerSecond / 100)
-      }
-      else {
-        1000 * (100 / tasksPerSecond)
-      }
-    }
-
-    if (maxZoom < 0) maxZoom = 1
-
+    val maxZoom = maxFinishTime - minLaunchTime
     <span class="expand-task-assignment-timeline">
       <span class="expand-task-assignment-timeline-arrow arrow-closed"></span>
       <a>Event Timeline {