diff --git a/hadoop-yarn-project/CHANGES.txt b/hadoop-yarn-project/CHANGES.txt
index f5dc39d2c6..962e040a61 100644
--- a/hadoop-yarn-project/CHANGES.txt
+++ b/hadoop-yarn-project/CHANGES.txt
@@ -870,6 +870,9 @@ Release 2.7.0 - UNRELEASED
     removing inconsistencies in the default values. (Junping Du and Karthik
     Kambatla via vinodkv)
 
+    YARN-3430. Made headroom data available on app attempt page of RM WebUI.
+    (Xuan Gong via zjshen)
+
 Release 2.6.0 - 2014-11-18
 
   INCOMPATIBLE CHANGES
diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/webapp/RMAppAttemptBlock.java b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/webapp/RMAppAttemptBlock.java
index 1861874eaa..1831920517 100644
--- a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/webapp/RMAppAttemptBlock.java
+++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/webapp/RMAppAttemptBlock.java
@@ -166,10 +166,12 @@ protected void createAttemptHeadRoomTable(Block html) {
     if (attempt != null) {
       if (!isApplicationInFinalState(YarnApplicationAttemptState
           .valueOf(attempt.getAppAttemptState().toString()))) {
+        RMAppAttemptMetrics metrics = attempt.getRMAppAttemptMetrics();
         DIV<Hamlet> pdiv = html._(InfoBlock.class).div(_INFO_WRAP);
         info("Application Attempt Overview").clear();
         info("Application Attempt Metrics")._(
-          "Application Attempt Headroom : ", 0);
+          "Application Attempt Headroom : ", metrics == null ? "N/A" :
+            metrics.getApplicationAttemptHeadroom());
         pdiv._();
       }
     }