From d9198b2d1bcd1a269ba929ad03420dc58b0fcb81 Mon Sep 17 00:00:00 2001
From: Kihwal Lee <kihwal@apache.org>
Date: Wed, 29 Jan 2020 11:07:50 -0600
Subject: [PATCH] HDFS-15146. TestBalancerRPCDelay.testBalancerRPCDelay fails
 intermittently. Contributed by Ahmed Hussein.

---
 .../apache/hadoop/hdfs/server/balancer/TestBalancer.java  | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/balancer/TestBalancer.java b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/balancer/TestBalancer.java
index c8456b127b0..830dc0ed809 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/balancer/TestBalancer.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/balancer/TestBalancer.java
@@ -844,6 +844,7 @@ public class TestBalancer {
         cluster.startDataNodes(conf, 1, true, null,
             new String[]{newRack}, null,new long[]{newCapacity});
         totalCapacity += newCapacity;
+        cluster.triggerHeartbeats();
       } else {
         //if running a test with "include list", include original nodes as well
         if (nodes.getNumberofIncludeNodes()>0) {
@@ -860,11 +861,13 @@ public class TestBalancer {
         if (nodes.getNames() != null) {
           cluster.startDataNodes(conf, nodes.getNumberofNewNodes(), true, null,
               newRacks, nodes.getNames(), newCapacities);
-          totalCapacity += newCapacity*nodes.getNumberofNewNodes();
+          cluster.triggerHeartbeats();
+          totalCapacity += newCapacity * nodes.getNumberofNewNodes();
         } else {  // host names are not specified
           cluster.startDataNodes(conf, nodes.getNumberofNewNodes(), true, null,
               newRacks, null, newCapacities);
-          totalCapacity += newCapacity*nodes.getNumberofNewNodes();
+          cluster.triggerHeartbeats();
+          totalCapacity += newCapacity * nodes.getNumberofNewNodes();
           //populate the include nodes
           if (nodes.getNumberofIncludeNodes() > 0) {
             int totalNodes = cluster.getDataNodes().size();
@@ -1781,6 +1784,7 @@ public class TestBalancer {
     // start up an empty node with the same capacity and on the same rack
     cluster.startDataNodes(conf, 1, true, null, new String[] { newRack },
         new long[] { newCapacity });
+    cluster.triggerHeartbeats();
 
     // Case1: Simulate first balancer by creating 'balancer.id' file. It
     // will keep this file until the balancing operation is completed.