Revert "YARN-9615. Add dispatcher metrics to RM. Contributed by Qi Zhu."

This reverts commit 369f75b7a7f62ba454cc2a102ded6c2c947e80e5.

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-common/src/main/java/org/apache/hadoop/yarn/event/AsyncDispatcher.java

@@ -26,9 +26,6 @@ import java.util.Map;
 import java.util.concurrent.BlockingQueue;
 import java.util.concurrent.LinkedBlockingQueue;
 
-import org.apache.hadoop.yarn.metrics.EventTypeMetrics;
-import org.apache.hadoop.yarn.util.Clock;
-import org.apache.hadoop.yarn.util.MonotonicClock;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.slf4j.Marker;
@@ -88,11 +85,6 @@ public class AsyncDispatcher extends AbstractService implements Dispatcher {
   protected final Map<Class<? extends Enum>, EventHandler> eventDispatchers;
   private boolean exitOnDispatchException = true;
 
-  private Map<Class<? extends Enum>,
-      EventTypeMetrics> eventTypeMetricsMap;
-
-  private Clock clock = new MonotonicClock();
-
   /**
    * The thread name for dispatcher.
    */
@@ -106,8 +98,6 @@ public class AsyncDispatcher extends AbstractService implements Dispatcher {
     super("Dispatcher");
     this.eventQueue = eventQueue;
     this.eventDispatchers = new HashMap<Class<? extends Enum>, EventHandler>();
-    this.eventTypeMetricsMap = new HashMap<Class<? extends Enum>,
-        EventTypeMetrics>();
   }
 
   /**
@@ -145,16 +135,7 @@ public class AsyncDispatcher extends AbstractService implements Dispatcher {
             return;
           }
           if (event != null) {
-            if (eventTypeMetricsMap.
-                get(event.getType().getDeclaringClass()) != null) {
-              long startTime = clock.getTime();
-              dispatch(event);
-              eventTypeMetricsMap.get(event.getType().getDeclaringClass())
-                  .increment(event.getType(),
-                      clock.getTime() - startTime);
-            } else {
-              dispatch(event);
-            }
+            dispatch(event);
             if (printTrigger) {
               //Log the latest dispatch event type
               // may cause the too many events queued
@@ -388,9 +369,4 @@ public class AsyncDispatcher extends AbstractService implements Dispatcher {
   protected boolean isStopped() {
     return stopped;
   }
-
-  public void addMetrics(EventTypeMetrics metrics,
-      Class<? extends Enum> eventClass) {
-    eventTypeMetricsMap.put(eventClass, metrics);
-  }
 }

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-common/src/main/java/org/apache/hadoop/yarn/event/EventDispatcher.java

@@ -19,9 +19,6 @@
 package org.apache.hadoop.yarn.event;
 
 import org.apache.hadoop.thirdparty.com.google.common.annotations.VisibleForTesting;
-import org.apache.hadoop.yarn.metrics.EventTypeMetrics;
-import org.apache.hadoop.yarn.util.Clock;
-import org.apache.hadoop.yarn.util.MonotonicClock;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.slf4j.Marker;
@@ -50,15 +47,12 @@ public class EventDispatcher<T extends Event> extends
   private final Thread eventProcessor;
   private volatile boolean stopped = false;
   private boolean shouldExitOnError = true;
-  private EventTypeMetrics metrics;
 
   private static final Logger LOG =
       LoggerFactory.getLogger(EventDispatcher.class);
   private static final Marker FATAL =
       MarkerFactory.getMarker("FATAL");
 
-  private Clock clock = new MonotonicClock();
-
   private final class EventProcessor implements Runnable {
     @Override
     public void run() {
@@ -74,14 +68,7 @@ public class EventDispatcher<T extends Event> extends
         }
 
         try {
-          if (metrics != null) {
-            long startTime = clock.getTime();
-            handler.handle(event);
-            metrics.increment(event.getType(),
-                clock.getTime() - startTime);
-          } else {
-            handler.handle(event);
-          }
+          handler.handle(event);
         } catch (Throwable t) {
           // An error occurred, but we are shutting down anyway.
           // If it was an InterruptedException, the very act of
@@ -149,9 +136,4 @@ public class EventDispatcher<T extends Event> extends
   public void disableExitOnError() {
     shouldExitOnError = false;
   }
-
-  public void setMetrics(EventTypeMetrics metrics) {
-    this.metrics = metrics;
-  }
-
 }

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-common/src/main/java/org/apache/hadoop/yarn/metrics/DisableEventTypeMetrics.java

@@ -1,42 +0,0 @@
-/**
- * Licensed to the Apache Software Foundation (ASF) under one
- * or more contributor license agreements.  See the NOTICE file
- * distributed with this work for additional information
- * regarding copyright ownership.  The ASF licenses this file
- * to you under the Apache License, Version 2.0 (the
- * "License"); you may not use this file except in compliance
- * with the License.  You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-package org.apache.hadoop.yarn.metrics;
-
-import org.apache.hadoop.classification.InterfaceAudience;
-import org.apache.hadoop.metrics2.MetricsCollector;
-import org.apache.hadoop.metrics2.annotation.Metrics;
-
-@InterfaceAudience.Private
-@Metrics(context="yarn")
-public class DisableEventTypeMetrics implements EventTypeMetrics {
-  @Override
-  public void increment(Enum type, long processingTimeUs) {
-    //nop
-    return;
-  }
-  @Override
-  public void getMetrics(MetricsCollector collector, boolean all) {
-    //nop
-    return;
-  }
-
-  @Override
-  public long get(Enum type) {
-    return 0;
-  }
-}

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-common/src/main/java/org/apache/hadoop/yarn/metrics/EventTypeMetrics.java

@@ -1,32 +0,0 @@
-/**
- * Licensed to the Apache Software Foundation (ASF) under one
- * or more contributor license agreements.  See the NOTICE file
- * distributed with this work for additional information
- * regarding copyright ownership.  The ASF licenses this file
- * to you under the Apache License, Version 2.0 (the
- * "License"); you may not use this file except in compliance
- * with the License.  You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-package org.apache.hadoop.yarn.metrics;
-
-import org.apache.hadoop.classification.InterfaceAudience;
-import org.apache.hadoop.metrics2.MetricsSource;
-import org.apache.hadoop.metrics2.annotation.Metrics;
-
-@InterfaceAudience.Private
-@Metrics(context="yarn")
-public interface EventTypeMetrics<T extends Enum<T>>
-    extends MetricsSource {
-
-  void increment(T type, long processingTimeUs);
-
-  long get(T type);
-}

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-common/src/main/java/org/apache/hadoop/yarn/metrics/GenericEventTypeMetrics.java

@@ -1,160 +0,0 @@
-/**
- * Licensed to the Apache Software Foundation (ASF) under one
- * or more contributor license agreements.  See the NOTICE file
- * distributed with this work for additional information
- * regarding copyright ownership.  The ASF licenses this file
- * to you under the Apache License, Version 2.0 (the
- * "License"); you may not use this file except in compliance
- * with the License.  You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-package org.apache.hadoop.yarn.metrics;
-
-import org.apache.hadoop.classification.InterfaceAudience;
-import org.apache.hadoop.metrics2.MetricsCollector;
-import org.apache.hadoop.metrics2.MetricsInfo;
-import org.apache.hadoop.metrics2.MetricsSystem;
-import org.apache.hadoop.metrics2.annotation.Metrics;
-import org.apache.hadoop.metrics2.lib.MetricsRegistry;
-import org.apache.hadoop.metrics2.lib.MutableGaugeLong;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-
-import java.util.EnumMap;
-
-@InterfaceAudience.Private
-@Metrics(context="yarn")
-public class GenericEventTypeMetrics<T extends Enum<T>>
-    implements EventTypeMetrics<T> {
-
-  static final Logger LOG =
-      LoggerFactory.getLogger(GenericEventTypeMetrics.class);
-
-  private final EnumMap<T, MutableGaugeLong> eventCountMetrics;
-  private final EnumMap<T, MutableGaugeLong> processingTimeMetrics;
-  private final MetricsRegistry registry;
-  private final MetricsSystem ms;
-  private final MetricsInfo info;
-  private final Class<T> enumClass;
-
-  private boolean isInitialized = false;
-
-  public GenericEventTypeMetrics(MetricsInfo info, MetricsSystem ms,
-                                 final T[] enums, Class<T> enumClass) {
-    this.enumClass = enumClass;
-    this.eventCountMetrics = new EnumMap<>(this.enumClass);
-    this.processingTimeMetrics = new EnumMap<>(this.enumClass);
-    this.ms = ms;
-    this.info = info;
-    this.registry = new MetricsRegistry(this.info);
-
-    //Initialize enum
-    for (final T type : enums) {
-      String eventCountMetricsName =
-          type.toString() + "_" + "event_count";
-      String processingTimeMetricsName =
-          type.toString() + "_" + "processing_time";
-      eventCountMetrics.put(type, this.registry.
-          newGauge(eventCountMetricsName, eventCountMetricsName, 0L));
-      processingTimeMetrics.put(type, this.registry.
-          newGauge(processingTimeMetricsName, processingTimeMetricsName, 0L));
-    }
-  }
-
-  public synchronized GenericEventTypeMetrics registerMetrics() {
-    if (!isInitialized) {
-      // Register with the MetricsSystems
-      if (this.ms != null) {
-        LOG.info("Registering GenericEventTypeMetrics");
-        ms.register(info.name(),
-            info.description(), this);
-        isInitialized = true;
-      }
-    }
-    return this;
-  }
-
-  @Override
-  public void increment(T type, long processingTimeUs) {
-    if (eventCountMetrics.get(type) != null) {
-      eventCountMetrics.get(type).incr();
-      processingTimeMetrics.get(type).incr(processingTimeUs);
-    }
-  }
-
-  @Override
-  public long get(T type) {
-    return eventCountMetrics.get(type).value();
-  }
-
-  public long getTotalProcessingTime(T type) {
-    return processingTimeMetrics.get(type).value();
-  }
-
-  public EnumMap<T, MutableGaugeLong> getEventCountMetrics() {
-    return eventCountMetrics;
-  }
-
-  public EnumMap<T, MutableGaugeLong> getProcessingTimeMetrics() {
-    return processingTimeMetrics;
-  }
-
-  public MetricsRegistry getRegistry() {
-    return registry;
-  }
-
-  public MetricsInfo getInfo() {
-    return info;
-  }
-
-  @Override
-  public void getMetrics(MetricsCollector collector, boolean all) {
-    registry.snapshot(collector.addRecord(registry.info()), all);
-  }
-
-  public Class<T> getEnumClass() {
-    return enumClass;
-  }
-
-  /** Builder class for GenericEventTypeMetrics. */
-  public static class EventTypeMetricsBuilder<T extends Enum<T>>{
-    public EventTypeMetricsBuilder() {
-    }
-
-    public EventTypeMetricsBuilder setEnumClass(Class<T> enumClassValue) {
-      this.enumClass = enumClassValue;
-      return this;
-    }
-
-    public EventTypeMetricsBuilder setEnums(T[] enumsValue) {
-      this.enums = enumsValue.clone();
-      return this;
-    }
-
-    public EventTypeMetricsBuilder setInfo(MetricsInfo infoValue) {
-      this.info = infoValue;
-      return this;
-    }
-
-    public EventTypeMetricsBuilder setMs(MetricsSystem msValue) {
-      this.ms = msValue;
-      return this;
-    }
-
-    public GenericEventTypeMetrics build() {
-      return new GenericEventTypeMetrics(info, ms, enums, enumClass);
-    }
-
-    private MetricsSystem ms;
-    private MetricsInfo info;
-    private Class<T> enumClass;
-    private T[] enums;
-  }
-}

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-common/src/test/java/org/apache/hadoop/yarn/event/TestAsyncDispatcher.java

@@ -20,20 +20,9 @@ package org.apache.hadoop.yarn.event;
 
 import java.lang.reflect.Field;
 import java.lang.reflect.Modifier;
-import java.util.HashMap;
-import java.util.HashSet;
-import java.util.Map;
-import java.util.Set;
 import java.util.concurrent.BlockingQueue;
 import java.util.concurrent.LinkedBlockingQueue;
 
-
-import org.apache.hadoop.metrics2.AbstractMetric;
-import org.apache.hadoop.metrics2.MetricsRecord;
-import org.apache.hadoop.metrics2.impl.MetricsCollectorImpl;
-import org.apache.hadoop.metrics2.lib.DefaultMetricsSystem;
-import org.apache.hadoop.test.GenericTestUtils;
-import org.apache.hadoop.yarn.metrics.GenericEventTypeMetrics;
 import org.slf4j.Logger;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.yarn.conf.YarnConfiguration;
@@ -41,7 +30,6 @@ import org.apache.hadoop.yarn.exceptions.YarnRuntimeException;
 import org.junit.Assert;
 import org.junit.Test;
 
-import static org.apache.hadoop.metrics2.lib.Interns.info;
 import static org.junit.Assert.assertEquals;
 import static org.mockito.Mockito.*;
 
@@ -130,7 +118,7 @@ public class TestAsyncDispatcher {
   }
 
   private enum TestEnum {
-    TestEventType, TestEventType2
+    TestEventType
   }
 
   @SuppressWarnings({ "rawtypes", "unchecked" })
@@ -242,171 +230,5 @@ public class TestAsyncDispatcher {
     }
   }
 
-  @Test
-  public void testMetricsForDispatcher() throws Exception {
-    YarnConfiguration conf = new YarnConfiguration();
-    AsyncDispatcher dispatcher = null;
-
-    try {
-      dispatcher = new AsyncDispatcher("RM Event dispatcher");
-
-      GenericEventTypeMetrics genericEventTypeMetrics =
-          new GenericEventTypeMetrics.EventTypeMetricsBuilder()
-              .setMs(DefaultMetricsSystem.instance())
-              .setInfo(info("GenericEventTypeMetrics for "
-                      + TestEnum.class.getName(),
-                  "Metrics for " + dispatcher.getName()))
-              .setEnumClass(TestEnum.class)
-              .setEnums(TestEnum.class.getEnumConstants())
-              .build().registerMetrics();
-
-      // We can the metrics enabled for TestEnum
-      dispatcher.addMetrics(genericEventTypeMetrics,
-          genericEventTypeMetrics.getEnumClass());
-      dispatcher.init(conf);
-
-      // Register handler
-      dispatcher.register(TestEnum.class, new TestHandler());
-      dispatcher.start();
-
-      for (int i = 0; i < 3; ++i) {
-        Event event = mock(Event.class);
-        when(event.getType()).thenReturn(TestEnum.TestEventType);
-        dispatcher.getEventHandler().handle(event);
-      }
-
-      for (int i = 0; i < 2; ++i) {
-        Event event = mock(Event.class);
-        when(event.getType()).thenReturn(TestEnum.TestEventType2);
-        dispatcher.getEventHandler().handle(event);
-      }
-
-      // Check event type count.
-      GenericTestUtils.waitFor(() -> genericEventTypeMetrics.
-          get(TestEnum.TestEventType) == 3, 1000, 10000);
-
-      GenericTestUtils.waitFor(() -> genericEventTypeMetrics.
-          get(TestEnum.TestEventType2) == 2, 1000, 10000);
-
-      // Check time spend.
-      Assert.assertTrue(genericEventTypeMetrics.
-          getTotalProcessingTime(TestEnum.TestEventType)
-          >= 1500*3);
-      Assert.assertTrue(genericEventTypeMetrics.
-          getTotalProcessingTime(TestEnum.TestEventType)
-          < 1500*4);
-
-      Assert.assertTrue(genericEventTypeMetrics.
-          getTotalProcessingTime(TestEnum.TestEventType2)
-          >= 1500*2);
-      Assert.assertTrue(genericEventTypeMetrics.
-          getTotalProcessingTime(TestEnum.TestEventType2)
-          < 1500*3);
-
-      // Make sure metrics consistent.
-      Assert.assertEquals(Long.toString(genericEventTypeMetrics.
-              get(TestEnum.TestEventType)),
-          genericEventTypeMetrics.
-              getRegistry().get("TestEventType_event_count").toString());
-      Assert.assertEquals(Long.toString(genericEventTypeMetrics.
-              get(TestEnum.TestEventType2)),
-          genericEventTypeMetrics.
-              getRegistry().get("TestEventType2_event_count").toString());
-      Assert.assertEquals(Long.toString(genericEventTypeMetrics.
-              getTotalProcessingTime(TestEnum.TestEventType)),
-          genericEventTypeMetrics.
-              getRegistry().get("TestEventType_processing_time").toString());
-      Assert.assertEquals(Long.toString(genericEventTypeMetrics.
-              getTotalProcessingTime(TestEnum.TestEventType2)),
-          genericEventTypeMetrics.
-              getRegistry().get("TestEventType2_processing_time").toString());
-
-    } finally {
-      dispatcher.close();
-    }
-
-  }
-
-  @Test
-  public void testDispatcherMetricsHistogram() throws Exception {
-    YarnConfiguration conf = new YarnConfiguration();
-    AsyncDispatcher dispatcher = null;
-
-    try {
-      dispatcher = new AsyncDispatcher("RM Event dispatcher");
-
-      GenericEventTypeMetrics genericEventTypeMetrics =
-          new GenericEventTypeMetrics.EventTypeMetricsBuilder()
-              .setMs(DefaultMetricsSystem.instance())
-              .setInfo(info("GenericEventTypeMetrics for "
-                      + TestEnum.class.getName(),
-                  "Metrics for " + dispatcher.getName()))
-              .setEnumClass(TestEnum.class)
-              .setEnums(TestEnum.class.getEnumConstants())
-              .build().registerMetrics();
-
-      // We can the metrics enabled for TestEnum
-      dispatcher.addMetrics(genericEventTypeMetrics,
-          genericEventTypeMetrics.getEnumClass());
-      dispatcher.init(conf);
-
-      // Register handler
-      dispatcher.register(TestEnum.class, new TestHandler());
-      dispatcher.start();
-
-      for (int i = 0; i < 3; ++i) {
-        Event event = mock(Event.class);
-        when(event.getType()).thenReturn(TestEnum.TestEventType);
-        dispatcher.getEventHandler().handle(event);
-      }
-
-      for (int i = 0; i < 2; ++i) {
-        Event event = mock(Event.class);
-        when(event.getType()).thenReturn(TestEnum.TestEventType2);
-        dispatcher.getEventHandler().handle(event);
-      }
-
-      // Check event type count.
-      GenericTestUtils.waitFor(() -> genericEventTypeMetrics.
-          get(TestEnum.TestEventType) == 3, 1000, 10000);
-
-      GenericTestUtils.waitFor(() -> genericEventTypeMetrics.
-          get(TestEnum.TestEventType2) == 2, 1000, 10000);
-
-      // submit actual values
-      Map<String, Long> expectedValues = new HashMap<>();
-      expectedValues.put("TestEventType_event_count",
-          genericEventTypeMetrics.get(TestEnum.TestEventType));
-      expectedValues.put("TestEventType_processing_time",
-          genericEventTypeMetrics.
-              getTotalProcessingTime(TestEnum.TestEventType));
-      expectedValues.put("TestEventType2_event_count",
-          genericEventTypeMetrics.get(TestEnum.TestEventType2));
-      expectedValues.put("TestEventType2_processing_time",
-          genericEventTypeMetrics.
-              getTotalProcessingTime(TestEnum.TestEventType2));
-      Set<String> testResults = new HashSet<>();
+}
 
-      MetricsCollectorImpl collector = new MetricsCollectorImpl();
-      genericEventTypeMetrics.getMetrics(collector, true);
-
-      for (MetricsRecord record : collector.getRecords()) {
-        for (AbstractMetric metric : record.metrics()) {
-          String metricName = metric.name();
-          if (expectedValues.containsKey(metricName)) {
-            Long expectedValue = expectedValues.get(metricName);
-            Assert.assertEquals(
-                "Metric " + metricName + " doesn't have expected value",
-                expectedValue, metric.value());
-            testResults.add(metricName);
-          }
-        }
-      }
-      Assert.assertEquals(expectedValues.keySet(), testResults);
-
-    } finally {
-      dispatcher.close();
-    }
-
-  }
-}

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

@@ -1,42 +0,0 @@
-/**
- * Licensed to the Apache Software Foundation (ASF) under one
- * or more contributor license agreements.  See the NOTICE file
- * distributed with this work for additional information
- * regarding copyright ownership.  The ASF licenses this file
- * to you under the Apache License, Version 2.0 (the
- * "License"); you may not use this file except in compliance
- * with the License.  You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-package org.apache.hadoop.yarn.server.resourcemanager;
-
-import org.apache.hadoop.metrics2.lib.DefaultMetricsSystem;
-import org.apache.hadoop.yarn.metrics.GenericEventTypeMetrics;
-
-import static org.apache.hadoop.metrics2.lib.Interns.info;
-
-public final class GenericEventTypeMetricsManager {
-
-  private GenericEventTypeMetricsManager() {
-    // nothing to do
-  }
-
-  // Construct a GenericEventTypeMetrics for dispatcher
-  public static <T extends Enum<T>> GenericEventTypeMetrics
-      create(String dispatcherName, Class<T> eventTypeClass) {
-    return new GenericEventTypeMetrics.EventTypeMetricsBuilder<T>()
-        .setMs(DefaultMetricsSystem.instance())
-        .setInfo(info("GenericEventTypeMetrics for " + eventTypeClass.getName(),
-            "Metrics for " + dispatcherName))
-        .setEnumClass(eventTypeClass)
-        .setEnums(eventTypeClass.getEnumConstants())
-        .build().registerMetrics();
-  }
-}

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

@@ -21,7 +21,6 @@ package org.apache.hadoop.yarn.server.resourcemanager;
 import org.apache.hadoop.thirdparty.com.google.common.annotations.VisibleForTesting;
 import com.sun.jersey.spi.container.servlet.ServletContainer;
 
-import org.apache.hadoop.yarn.metrics.GenericEventTypeMetrics;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.slf4j.Marker;
@@ -63,7 +62,6 @@ import org.apache.hadoop.yarn.event.AsyncDispatcher;
 import org.apache.hadoop.yarn.event.Dispatcher;
 import org.apache.hadoop.yarn.event.EventDispatcher;
 import org.apache.hadoop.yarn.event.EventHandler;
-
 import org.apache.hadoop.yarn.exceptions.YarnException;
 import org.apache.hadoop.yarn.exceptions.YarnRuntimeException;
 import org.apache.hadoop.yarn.nodelabels.NodeAttributesManager;
@@ -451,23 +449,11 @@ public class ResourceManager extends CompositeService
   }
 
   protected EventHandler<SchedulerEvent> createSchedulerEventDispatcher() {
-    EventDispatcher dispatcher = new
-        EventDispatcher(this.scheduler, "SchedulerEventDispatcher");
-    dispatcher.
-        setMetrics(GenericEventTypeMetricsManager.
-            create(dispatcher.getName(), SchedulerEventType.class));
-    return dispatcher;
+    return new EventDispatcher(this.scheduler, "SchedulerEventDispatcher");
   }
 
   protected Dispatcher createDispatcher() {
-    AsyncDispatcher dispatcher = new AsyncDispatcher("RM Event dispatcher");
-    GenericEventTypeMetrics genericEventTypeMetrics =
-        GenericEventTypeMetricsManager.
-        create(dispatcher.getName(), NodesListManagerEventType.class);
-    // We can add more
-    dispatcher.addMetrics(genericEventTypeMetrics,
-        genericEventTypeMetrics.getEnumClass());
-    return dispatcher;
+    return new AsyncDispatcher("RM Event dispatcher");
   }
 
   protected ResourceScheduler createScheduler() {

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

@@ -29,7 +29,6 @@ import java.util.concurrent.TimeoutException;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.fs.CommonConfigurationKeysPublic;
 import org.apache.hadoop.http.lib.StaticUserWebFilter;
-import org.apache.hadoop.metrics2.lib.DefaultMetricsSystem;
 import org.apache.hadoop.net.NetworkTopology;
 import org.apache.hadoop.security.AuthenticationFilterInitializer;
 import org.apache.hadoop.security.UserGroupInformation;
@@ -74,7 +73,6 @@ public class TestResourceManager {
   public void setUp() throws Exception {
     YarnConfiguration conf = new YarnConfiguration();
     UserGroupInformation.setConfiguration(conf);
-    DefaultMetricsSystem.setMiniClusterMode(true);
     resourceManager = new ResourceManager();
     resourceManager.init(conf);
     resourceManager.getRMContext().getContainerTokenSecretManager().rollMasterKey();

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/test/java/org/apache/hadoop/yarn/server/resourcemanager/scheduler/TestSchedulerHealth.java

@@ -18,7 +18,6 @@
 
 package org.apache.hadoop.yarn.server.resourcemanager.scheduler;
 
-import org.apache.hadoop.metrics2.lib.DefaultMetricsSystem;
 import org.apache.hadoop.net.NetworkTopology;
 import org.apache.hadoop.util.Time;
 import org.apache.hadoop.yarn.api.records.ContainerId;
@@ -53,7 +52,6 @@ public class TestSchedulerHealth {
   private ResourceManager resourceManager;
 
   public void setup() {
-    DefaultMetricsSystem.setMiniClusterMode(true);
     resourceManager = new ResourceManager() {
       @Override
       protected RMNodeLabelsManager createNodeLabelManager() {

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/test/java/org/apache/hadoop/yarn/server/resourcemanager/scheduler/capacity/TestCapacityScheduler.java

@@ -212,7 +212,6 @@ public class TestCapacityScheduler extends CapacitySchedulerTestBase {
   @Before
   public void setUp() throws Exception {
     ResourceUtils.resetResourceTypes(new Configuration());
-    DefaultMetricsSystem.setMiniClusterMode(true);
     resourceManager = new ResourceManager() {
       @Override
       protected RMNodeLabelsManager createNodeLabelManager() {