SPARK-5768: Fix for incorrect memory in Spark UI

Author: rekhajoshm

core/src/main/scala/org/apache/spark/ui/ToolTips.scala

@@ -35,6 +35,9 @@ private[spark] object ToolTips {
 
   val OUTPUT = "Bytes and records written to Hadoop."
 
+  val STORAGE_MEMORY =
+    "Total memory used for caching of the total available memory for caching.This is the storage memory used on the executor."
+
   val SHUFFLE_WRITE =
     "Bytes and records written to disk in order to be read by a shuffle in a future stage."
 

core/src/main/scala/org/apache/spark/ui/exec/ExecutorsPage.scala

@@ -67,7 +67,7 @@ private[ui] class ExecutorsPage(
           <th>Executor ID</th>
           <th>Address</th>
           <th>RDD Blocks</th>
-          <th>Memory Used</th>
+          <th><span data-toggle="tooltip" title={ToolTips.STORAGE_MEMORY}>Storage Memory</span></th>
           <th>Disk Used</th>
           <th>Active Tasks</th>
           <th>Failed Tasks</th>