From 1f28703d936873ce5ecf08091862af7afa6f0340 Mon Sep 17 00:00:00 2001
From: Steve Loughran <stevel@apache.org>
Date: Wed, 16 Sep 2015 10:08:18 +0100
Subject: [PATCH] HDFS-9072. Fix random failures in TestJMXGet.  (J.Andreina
 via stevel)

---
 hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt                    | 3 +++
 .../src/test/java/org/apache/hadoop/tools/TestJMXGet.java      | 3 +++
 2 files changed, 6 insertions(+)

diff --git a/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt b/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt
index 44fb9852935..c5f83f53584 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt
+++ b/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt
@@ -1005,6 +1005,9 @@ Release 2.8.0 - UNRELEASED
     HDFS-9067. o.a.h.hdfs.server.datanode.fsdataset.impl.TestLazyWriter
     is failing in trunk (Surendra Singh Lilhore via vinayakumarb)
 
+    HDFS-9072. Fix random failures in TestJMXGet.
+    (J.Andreina via stevel)
+
 Release 2.7.2 - UNRELEASED
 
   INCOMPATIBLE CHANGES
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/tools/TestJMXGet.java b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/tools/TestJMXGet.java
index c69e73a0598..aef18fb4850 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/tools/TestJMXGet.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/tools/TestJMXGet.java
@@ -114,10 +114,12 @@ public class TestJMXGet {
     assertTrue("error printAllValues", checkPrintAllValues(jmx));
 
     //get some data from different source
+    DFSTestUtil.waitForMetric(jmx, "NumLiveDataNodes", numDatanodes);
     assertEquals(numDatanodes, Integer.parseInt(
         jmx.getValue("NumLiveDataNodes")));
     assertGauge("CorruptBlocks", Long.parseLong(jmx.getValue("CorruptBlocks")),
                 getMetrics("FSNamesystem"));
+    DFSTestUtil.waitForMetric(jmx, "NumOpenConnections", numDatanodes);
     assertEquals(numDatanodes, Integer.parseInt(
         jmx.getValue("NumOpenConnections")));
 
@@ -161,6 +163,7 @@ public class TestJMXGet {
     String serviceName = "DataNode";
     jmx.setService(serviceName);
     jmx.init();
+    DFSTestUtil.waitForMetric(jmx, "BytesWritten", fileSize);
     assertEquals(fileSize, Integer.parseInt(jmx.getValue("BytesWritten")));
 
     cluster.shutdown();