YARN-4460. [Bug fix] RM fails to start when SMP is enabled. (Li Lu via Varun Saxena)

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/metrics/TimelineServiceV2Publisher.java

@@ -25,6 +25,7 @@ import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 import org.apache.hadoop.classification.InterfaceAudience.Private;
 import org.apache.hadoop.classification.InterfaceStability.Unstable;
+import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.security.UserGroupInformation;
 import org.apache.hadoop.yarn.api.records.ApplicationAttemptId;
 import org.apache.hadoop.yarn.api.records.ApplicationId;
@@ -76,13 +77,13 @@ public class TimelineServiceV2Publisher extends AbstractSystemMetricsPublisher {
   }
 
   @Override
-  protected void serviceStart() throws Exception {
-    super.serviceStart();
+  protected void serviceInit(Configuration conf) throws Exception {
+    super.serviceInit(conf);
+    getDispatcher().register(SystemMetricsEventType.class,
+        new TimelineV2EventHandler());
     publishContainerMetrics = getConfig().getBoolean(
         YarnConfiguration.RM_PUBLISH_CONTAINER_METRICS_ENABLED,
         YarnConfiguration.DEFAULT_RM_PUBLISH_CONTAINER_METRICS_ENABLED);
-    getDispatcher().register(SystemMetricsEventType.class,
-        new TimelineV2EventHandler());
   }
 
   @VisibleForTesting

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/test/java/org/apache/hadoop/yarn/server/resourcemanager/metrics/TestSystemMetricsPublisherForV2.java

@@ -156,7 +156,7 @@ public class TestSystemMetricsPublisherForV2 {
     try {
       Configuration conf = getTimelineV2Conf();
       conf.setBoolean(YarnConfiguration.RM_PUBLISH_CONTAINER_METRICS_ENABLED,
-          false);
+          YarnConfiguration.DEFAULT_RM_PUBLISH_CONTAINER_METRICS_ENABLED);
       metricsPublisher.init(conf);
       assertFalse(
           "Default configuration should not publish container Metrics from RM",
@@ -167,6 +167,9 @@ public class TestSystemMetricsPublisherForV2 {
       metricsPublisher = new TimelineServiceV2Publisher(mock(RMContext.class));
       conf = getTimelineV2Conf();
       metricsPublisher.init(conf);
+      assertTrue("Expected to have registered event handlers and set ready to "
+          + "publish events after init",
+          metricsPublisher.isPublishContainerMetrics());
       metricsPublisher.start();
       assertTrue("Expected to publish container Metrics from RM",
           metricsPublisher.isPublishContainerMetrics());