From 99bced167bfed56efdd3c78537769ee89756d33d Mon Sep 17 00:00:00 2001
From: Karthik Kambatla <kasha@apache.org>
Date: Wed, 2 Jul 2014 20:36:09 +0000
Subject: [PATCH] YARN-2241. ZKRMStateStore: On startup, show nicer messages if
 znodes already exist. (Robert Kanter via kasha)

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1607475 13f79535-47bb-0310-9956-ffa450edef68
---
 hadoop-yarn-project/CHANGES.txt               |  3 +++
 .../recovery/ZKRMStateStore.java              | 23 ++++++++++---------
 2 files changed, 15 insertions(+), 11 deletions(-)

diff --git a/hadoop-yarn-project/CHANGES.txt b/hadoop-yarn-project/CHANGES.txt
index f223854b88f..d7607260645 100644
--- a/hadoop-yarn-project/CHANGES.txt
+++ b/hadoop-yarn-project/CHANGES.txt
@@ -193,6 +193,9 @@ Release 2.5.0 - UNRELEASED
     TestContainersMonitor#testContainerKillOnMemoryOverflow.
     (Anubhav Dhoot via kasha)
 
+    YARN-2241. ZKRMStateStore: On startup, show nicer messages if znodes already 
+    exist. (Robert Kanter via kasha)
+
   OPTIMIZATIONS
 
   BUG FIXES 
diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/recovery/ZKRMStateStore.java b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/recovery/ZKRMStateStore.java
index 01bca39ad07..6dd4574b42e 100644
--- a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/recovery/ZKRMStateStore.java
+++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/recovery/ZKRMStateStore.java
@@ -279,20 +279,21 @@ public class ZKRMStateStore extends RMStateStore {
 
   private void createRootDir(final String rootPath) throws Exception {
     // For root dirs, we shouldn't use the doMulti helper methods
-    try {
-      new ZKAction<String>() {
-        @Override
-        public String run() throws KeeperException, InterruptedException {
+    new ZKAction<String>() {
+      @Override
+      public String run() throws KeeperException, InterruptedException {
+        try {
           return zkClient.create(rootPath, null, zkAcl, CreateMode.PERSISTENT);
+        } catch (KeeperException ke) {
+          if (ke.code() == Code.NODEEXISTS) {
+            LOG.debug(rootPath + "znode already exists!");
+            return null;
+          } else {
+            throw ke;
+          }
         }
-      }.runWithRetries();
-    } catch (KeeperException ke) {
-      if (ke.code() == Code.NODEEXISTS) {
-        LOG.debug(rootPath + "znode already exists!");
-      } else {
-        throw ke;
       }
-    }
+    }.runWithRetries();
   }
 
   private void logRootNodeAcls(String prefix) throws Exception {