YARN-7419. CapacityScheduler: Allow auto leaf queue creation after queue mapping. (Suma Shivaprasad via wangda)

Change-Id: Ia1704bb8cb5070e5b180b5a85787d7b9ca57ebc6

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

@@ -360,13 +360,8 @@ protected void recoverApplication(ApplicationStateData appState,
   private RMAppImpl createAndPopulateNewRMApp(
       ApplicationSubmissionContext submissionContext, long submitTime,
       String user, boolean isRecovery, long startTime) throws YarnException {
+
     if (!isRecovery) {
-      // Do queue mapping
-      if (rmContext.getQueuePlacementManager() != null) {
-        // We only do queue mapping when it's a new application
-        rmContext.getQueuePlacementManager().placeApplication(
-            submissionContext, user);
-      }
       // fail the submission if configured application timeout value is invalid
       RMServerUtils.validateApplicationTimeouts(
           submissionContext.getApplicationTimeouts());

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

@@ -0,0 +1,52 @@
+/**
+ * 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.placement;
+
+/**
+ * Each placement rule when it successfully places an application onto a queue
+ * returns a PlacementRuleContext which encapsulates the queue the
+ * application was mapped to and any parent queue for the queue (if configured)
+ */
+public class ApplicationPlacementContext {
+
+  private String queue;
+
+  private String parentQueue;
+
+  public ApplicationPlacementContext(String queue) {
+    this(queue,null);
+  }
+
+  public ApplicationPlacementContext(String queue, String parentQueue) {
+    this.queue = queue;
+    this.parentQueue = parentQueue;
+  }
+
+  public String getQueue() {
+    return queue;
+  }
+
+  public String getParentQueue() {
+    return parentQueue;
+  }
+
+  public boolean hasParentQueue() {
+    return parentQueue != null;
+  }
+}

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

@@ -23,7 +23,6 @@
 import java.util.concurrent.locks.ReentrantReadWriteLock.ReadLock;
 import java.util.concurrent.locks.ReentrantReadWriteLock.WriteLock;
 
-import org.apache.commons.lang.StringUtils;
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 import org.apache.hadoop.yarn.api.records.ApplicationSubmissionContext;
@@ -53,36 +52,33 @@ public void updateRules(List<PlacementRule> rules) {
     }
   }
 
-  public void placeApplication(ApplicationSubmissionContext asc, String user)
-      throws YarnException {
+  public ApplicationPlacementContext placeApplication(
+      ApplicationSubmissionContext asc, String user) throws YarnException {
+
     try {
       readLock.lock();
+
       if (null == rules || rules.isEmpty()) {
-        return;
+        return null;
       }
-      
-      String newQueueName = null;
+
+      ApplicationPlacementContext placement = null;
       for (PlacementRule rule : rules) {
-        newQueueName = rule.getQueueForApp(asc, user);
-        if (newQueueName != null) {
+        placement = rule.getPlacementForApp(asc, user);
+        if (placement != null) {
           break;
         }
       }
-      
+
       // Failed to get where to place application
-      if (null == newQueueName && null == asc.getQueue()) {
-        String msg = "Failed to get where to place application="
-            + asc.getApplicationId();
+      if (null == placement && null == asc.getQueue()) {
+        String msg = "Failed to get where to place application=" + asc
+            .getApplicationId();
         LOG.error(msg);
         throw new YarnException(msg);
       }
-      
-      // Set it to ApplicationSubmissionContext
-      if (!StringUtils.equals(asc.getQueue(), newQueueName)) {
-        LOG.info("Placed application=" + asc.getApplicationId() + " to queue="
-            + newQueueName + ", original queue=" + asc.getQueue());
-        asc.setQueue(newQueueName);
-      }
+
+      return placement;
     } finally {
       readLock.unlock();
     }

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

@@ -25,6 +25,7 @@
 import org.apache.hadoop.yarn.server.resourcemanager.RMContext;
 
 public abstract class PlacementRule {
+
   public String getName() {
     return this.getClass().getName();
   }
@@ -50,6 +51,6 @@ public void initialize(Map<String, String> parameters, RMContext rmContext)
    *         in the {@link PlacementManager} will take care
    *         </p>
    */
-  public abstract String getQueueForApp(ApplicationSubmissionContext asc,
-      String user) throws YarnException;
-}
+  public abstract ApplicationPlacementContext getPlacementForApp(
+      ApplicationSubmissionContext asc, String user) throws YarnException;
+}

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

@@ -19,8 +19,10 @@
 package org.apache.hadoop.yarn.server.resourcemanager.placement;
 
 import java.io.IOException;
+import java.util.ArrayList;
 import java.util.List;
 
+import org.apache.commons.lang.StringUtils;
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 import org.apache.hadoop.classification.InterfaceAudience.Private;
@@ -32,6 +34,15 @@
 import org.apache.hadoop.yarn.server.resourcemanager.placement.UserGroupMappingPlacementRule.QueueMapping.MappingType;
 
 import com.google.common.annotations.VisibleForTesting;
+import org.apache.hadoop.yarn.server.resourcemanager.scheduler.capacity.AutoCreatedLeafQueue;
+import org.apache.hadoop.yarn.server.resourcemanager.scheduler.capacity.CSQueue;
+import org.apache.hadoop.yarn.server.resourcemanager.scheduler.capacity.CapacitySchedulerConfiguration;
+import org.apache.hadoop.yarn.server.resourcemanager.scheduler.capacity.CapacitySchedulerContext;
+import org.apache.hadoop.yarn.server.resourcemanager.scheduler.capacity.CapacitySchedulerQueueManager;
+import org.apache.hadoop.yarn.server.resourcemanager.scheduler.capacity.LeafQueue;
+import org.apache.hadoop.yarn.server.resourcemanager.scheduler.capacity.ManagedParentQueue;
+
+import static org.apache.hadoop.yarn.server.resourcemanager.scheduler.capacity.CapacitySchedulerConfiguration.DOT;
 
 public class UserGroupMappingPlacementRule extends PlacementRule {
   private static final Log LOG = LogFactory
@@ -66,17 +77,41 @@ public String toString() {
     MappingType type;
     String source;
     String queue;
+    String parentQueue;
+
+    public final static String DELIMITER = ":";
 
     public QueueMapping(MappingType type, String source, String queue) {
       this.type = type;
       this.source = source;
       this.queue = queue;
+      this.parentQueue = null;
     }
-    
+
+    public QueueMapping(MappingType type, String source,
+        String queue, String parentQueue) {
+      this.type = type;
+      this.source = source;
+      this.queue = queue;
+      this.parentQueue = parentQueue;
+    }
+
     public String getQueue() {
       return queue;
     }
-    
+
+    public String getParentQueue() {
+      return parentQueue;
+    }
+
+    public MappingType getType() {
+      return type;
+    }
+
+    public String getSource() {
+      return source;
+    }
+
     @Override
     public int hashCode() {
       return super.hashCode();
@@ -93,6 +128,13 @@ public boolean equals(Object obj) {
         return false;
       }
     }
+
+    public String toString() {
+      return type.toString() + DELIMITER + source + DELIMITER +
+        (parentQueue != null ?
+        parentQueue + "." + queue :
+        queue);
+    }
   }
 
   public UserGroupMappingPlacementRule(boolean overrideWithQueueMappings,
@@ -102,26 +144,27 @@ public UserGroupMappingPlacementRule(boolean overrideWithQueueMappings,
     this.groups = groups;
   }
 
-  private String getMappedQueue(String user) throws IOException {
+  private ApplicationPlacementContext getPlacementForUser(String user)
+      throws IOException {
     for (QueueMapping mapping : mappings) {
       if (mapping.type == MappingType.USER) {
         if (mapping.source.equals(CURRENT_USER_MAPPING)) {
           if (mapping.queue.equals(CURRENT_USER_MAPPING)) {
-            return user;
+            return getPlacementContext(mapping, user);
           } else if (mapping.queue.equals(PRIMARY_GROUP_MAPPING)) {
-            return groups.getGroups(user).get(0);
+            return getPlacementContext(mapping, groups.getGroups(user).get(0));
           } else {
-            return mapping.queue;
+            return getPlacementContext(mapping);
           }
         }
         if (user.equals(mapping.source)) {
-          return mapping.queue;
+          return getPlacementContext(mapping);
         }
       }
       if (mapping.type == MappingType.GROUP) {
         for (String userGroups : groups.getGroups(user)) {
           if (userGroups.equals(mapping.source)) {
-            return mapping.queue;
+            return getPlacementContext(mapping);
           }
         }
       }
@@ -130,13 +173,14 @@ private String getMappedQueue(String user) throws IOException {
   }
 
   @Override
-  public String getQueueForApp(ApplicationSubmissionContext asc, String user)
+  public ApplicationPlacementContext getPlacementForApp(
+      ApplicationSubmissionContext asc, String user)
       throws YarnException {
     String queueName = asc.getQueue();
     ApplicationId applicationId = asc.getApplicationId();
     if (mappings != null && mappings.size() > 0) {
       try {
-        String mappedQueue = getMappedQueue(user);
+        ApplicationPlacementContext mappedQueue = getPlacementForUser(user);
         if (mappedQueue != null) {
           // We have a mapping, should we use it?
           if (queueName.equals(YarnConfiguration.DEFAULT_QUEUE_NAME)
@@ -153,10 +197,224 @@ public String getQueueForApp(ApplicationSubmissionContext asc, String user)
         throw new YarnException(message);
       }
     }
-    
-    return queueName;
+    return null;
   }
-  
+
+  private ApplicationPlacementContext getPlacementContext(
+      QueueMapping mapping) {
+    return getPlacementContext(mapping, mapping.getQueue());
+  }
+
+  private ApplicationPlacementContext getPlacementContext(QueueMapping mapping,
+      String leafQueueName) {
+    if (!StringUtils.isEmpty(mapping.parentQueue)) {
+      return new ApplicationPlacementContext(leafQueueName,
+          mapping.getParentQueue());
+    } else{
+      return new ApplicationPlacementContext(leafQueueName);
+    }
+  }
+
+  @VisibleForTesting
+  public static UserGroupMappingPlacementRule get(
+      CapacitySchedulerContext schedulerContext) throws IOException {
+    CapacitySchedulerConfiguration conf = schedulerContext.getConfiguration();
+    boolean overrideWithQueueMappings = conf.getOverrideWithQueueMappings();
+    LOG.info(
+        "Initialized queue mappings, override: " + overrideWithQueueMappings);
+
+    List<QueueMapping> queueMappings = conf.getQueueMappings();
+
+    // Get new user/group mappings
+    List<QueueMapping> newMappings = new ArrayList<>();
+
+    CapacitySchedulerQueueManager queueManager =
+        schedulerContext.getCapacitySchedulerQueueManager();
+
+    // check if mappings refer to valid queues
+    for (QueueMapping mapping : queueMappings) {
+
+      QueuePath queuePath = extractQueuePath(mapping.getQueue());
+      if (isStaticQueueMapping(mapping)) {
+        //Try getting queue by its leaf queue name
+        // without splitting into parent/leaf queues
+        CSQueue queue = queueManager.getQueue(mapping.getQueue());
+        if (ifQueueDoesNotExist(queue)) {
+          //Try getting the queue by extracting leaf and parent queue names
+          //Assuming its a potential auto created leaf queue
+          queue = queueManager.getQueue(queuePath.getLeafQueue());
+
+          if (ifQueueDoesNotExist(queue)) {
+            //if leaf queue does not exist,
+            // this could be a potential auto created leaf queue
+            //validate if parent queue is specified,
+            // then it should exist and
+            // be an instance of AutoCreateEnabledParentQueue
+            QueueMapping newMapping = validateAndGetAutoCreatedQueueMapping(
+                queueManager, mapping, queuePath);
+            if (newMapping == null) {
+              throw new IOException(
+                  "mapping contains invalid or non-leaf queue " + mapping
+                      .getQueue());
+            }
+            newMappings.add(newMapping);
+          } else{
+            QueueMapping newMapping = validateAndGetQueueMapping(queueManager,
+                queue, mapping, queuePath);
+            newMappings.add(newMapping);
+          }
+        } else{
+          // if queue exists, validate
+          //   if its an instance of leaf queue
+          //   if its an instance of auto created leaf queue,
+          // then extract parent queue name and update queue mapping
+          QueueMapping newMapping = validateAndGetQueueMapping(queueManager,
+              queue, mapping, queuePath);
+          newMappings.add(newMapping);
+        }
+      } else{
+        //If it is a dynamic queue mapping,
+        // we can safely assume leaf queue name does not have '.' in it
+        // validate
+        // if parent queue is specified, then
+        //  parent queue exists and an instance of AutoCreateEnabledParentQueue
+        //
+        QueueMapping newMapping = validateAndGetAutoCreatedQueueMapping(
+            queueManager, mapping, queuePath);
+        if (newMapping != null) {
+          newMappings.add(newMapping);
+        } else{
+          newMappings.add(mapping);
+        }
+      }
+    }
+
+    // initialize groups if mappings are present
+    if (newMappings.size() > 0) {
+      Groups groups = new Groups(conf);
+      return new UserGroupMappingPlacementRule(overrideWithQueueMappings,
+          newMappings, groups);
+    }
+
+    return null;
+  }
+
+  private static QueueMapping validateAndGetQueueMapping(
+      CapacitySchedulerQueueManager queueManager, CSQueue queue,
+      QueueMapping mapping, QueuePath queuePath) throws IOException {
+    if (!(queue instanceof LeafQueue)) {
+      throw new IOException(
+          "mapping contains invalid or non-leaf queue : " + mapping.getQueue());
+    }
+
+    if (queue instanceof AutoCreatedLeafQueue && queue
+        .getParent() instanceof ManagedParentQueue) {
+
+      QueueMapping newMapping = validateAndGetAutoCreatedQueueMapping(
+          queueManager, mapping, queuePath);
+      if (newMapping == null) {
+        throw new IOException(
+            "mapping contains invalid or non-leaf queue " + mapping.getQueue());
+      }
+      return newMapping;
+    }
+    return mapping;
+  }
+
+  private static boolean ifQueueDoesNotExist(CSQueue queue) {
+    return queue == null;
+  }
+
+  private static QueueMapping validateAndGetAutoCreatedQueueMapping(
+      CapacitySchedulerQueueManager queueManager, QueueMapping mapping,
+      QueuePath queuePath) throws IOException {
+    if (queuePath.hasParentQueue()) {
+      //if parent queue is specified,
+      // then it should exist and be an instance of ManagedParentQueue
+      validateParentQueue(queueManager.getQueue(queuePath.getParentQueue()),
+          queuePath.getParentQueue(), queuePath.getLeafQueue());
+      return new QueueMapping(mapping.getType(), mapping.getSource(),
+          queuePath.getLeafQueue(), queuePath.getParentQueue());
+    }
+
+    return null;
+  }
+
+  private static boolean isStaticQueueMapping(QueueMapping mapping) {
+    return !mapping.getQueue().contains(
+        UserGroupMappingPlacementRule.CURRENT_USER_MAPPING) && !mapping
+        .getQueue().contains(
+            UserGroupMappingPlacementRule.PRIMARY_GROUP_MAPPING);
+  }
+
+  private static class QueuePath {
+
+    public String parentQueue;
+    public String leafQueue;
+
+    public QueuePath(final String leafQueue) {
+      this.leafQueue = leafQueue;
+    }
+
+    public QueuePath(final String parentQueue, final String leafQueue) {
+      this.parentQueue = parentQueue;
+      this.leafQueue = leafQueue;
+    }
+
+    public String getParentQueue() {
+      return parentQueue;
+    }
+
+    public String getLeafQueue() {
+      return leafQueue;
+    }
+
+    public boolean hasParentQueue() {
+      return parentQueue != null;
+    }
+
+    @Override
+    public String toString() {
+      return parentQueue + DOT + leafQueue;
+    }
+  }
+
+  private static QueuePath extractQueuePath(String queueName)
+      throws IOException {
+    int parentQueueNameEndIndex = queueName.lastIndexOf(DOT);
+
+    if (parentQueueNameEndIndex > -1) {
+      final String parentQueue = queueName.substring(0, parentQueueNameEndIndex)
+          .trim();
+      final String leafQueue = queueName.substring(parentQueueNameEndIndex + 1)
+          .trim();
+      return new QueuePath(parentQueue, leafQueue);
+    }
+
+    return new QueuePath(queueName);
+  }
+
+  private static void validateParentQueue(CSQueue parentQueue,
+      String parentQueueName, String leafQueueName) throws IOException {
+    if (parentQueue == null) {
+      throw new IOException(
+          "mapping contains invalid or non-leaf queue [" + leafQueueName
+              + "] and invalid parent queue [" + parentQueueName + "]");
+    } else if (!(parentQueue instanceof ManagedParentQueue)) {
+      throw new IOException("mapping contains leaf queue [" + leafQueueName
+          + "] and invalid parent queue which "
+          + "does not have auto creation of leaf queues enabled ["
+          + parentQueueName + "]");
+    } else if (!parentQueue.getQueueName().equals(parentQueueName)) {
+      throw new IOException(
+          "mapping contains invalid or non-leaf queue [" + leafQueueName
+              + "] and invalid parent queue "
+              + "which does not match existing leaf queue's parent : ["
+              + parentQueueName + "] does not match [ " + parentQueue
+              .getQueueName() + "]");
+    }
+  }
+
   @VisibleForTesting
   public List<QueueMapping> getQueueMappings() {
     return mappings;

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

@@ -68,6 +68,7 @@
 import org.apache.hadoop.yarn.conf.YarnConfiguration;
 import org.apache.hadoop.yarn.event.Dispatcher;
 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.security.AMRMTokenIdentifier;
 import org.apache.hadoop.yarn.security.client.ClientToAMTokenIdentifier;
@@ -83,6 +84,8 @@
 import org.apache.hadoop.yarn.server.resourcemanager.blacklist.BlacklistManager;
 import org.apache.hadoop.yarn.server.resourcemanager.blacklist.DisabledBlacklistManager;
 import org.apache.hadoop.yarn.server.resourcemanager.blacklist.SimpleBlacklistManager;
+import org.apache.hadoop.yarn.server.resourcemanager.placement.ApplicationPlacementContext;
+import org.apache.hadoop.yarn.server.resourcemanager.placement.PlacementManager;
 import org.apache.hadoop.yarn.server.resourcemanager.recovery.RMStateStore.RMState;
 import org.apache.hadoop.yarn.server.resourcemanager.recovery.Recoverable;
 import org.apache.hadoop.yarn.server.resourcemanager.recovery.records.ApplicationStateData;
@@ -158,6 +161,8 @@ public class RMAppImpl implements RMApp, Recoverable {
 
   private boolean isNumAttemptsBeyondThreshold = false;
 
+
+
   // Mutable fields
   private long startTime;
   private long finishTime = 0;
@@ -1073,38 +1078,51 @@ public RMAppState transition(RMAppImpl app, RMAppEvent event) {
                   app.getUser(),
                   BuilderUtils.parseTokensConf(app.submissionContext));
         } catch (Exception e) {
-          String msg = "Failed to fetch user credentials from application:"
-              + e.getMessage();
+          String msg = "Failed to fetch user credentials from application:" + e
+              .getMessage();
           app.diagnostics.append(msg);
           LOG.error(msg, e);
         }
       }
 
-      for (Map.Entry<ApplicationTimeoutType, Long> timeout :
-        app.applicationTimeouts.entrySet()) {
+      for (Map.Entry<ApplicationTimeoutType, Long> timeout : app.applicationTimeouts
+          .entrySet()) {
         app.rmContext.getRMAppLifetimeMonitor().registerApp(app.applicationId,
             timeout.getKey(), timeout.getValue());
         if (LOG.isDebugEnabled()) {
           long remainingTime = timeout.getValue() - app.systemClock.getTime();
           LOG.debug("Application " + app.applicationId
               + " is registered for timeout monitor, type=" + timeout.getKey()
-              + " remaining timeout="
-              + (remainingTime > 0 ? remainingTime / 1000 : 0) + " seconds");
+              + " remaining timeout=" + (remainingTime > 0 ?
+              remainingTime / 1000 :
+              0) + " seconds");
         }
       }
 
+      ApplicationPlacementContext placementContext = null;
+      try {
+        placementContext = placeApplication(app.rmContext,
+            app.submissionContext, app.user);
+      } catch (Exception e) {
+        String msg = "Failed to place application to queue :" + e.getMessage();
+        app.diagnostics.append(msg);
+        LOG.error(msg, e);
+      }
+
       // No existent attempts means the attempt associated with this app was not
       // started or started but not yet saved.
       if (app.attempts.isEmpty()) {
-        app.scheduler.handle(new AppAddedSchedulerEvent(app.user,
-            app.submissionContext, false, app.applicationPriority));
+        app.scheduler.handle(
+            new AppAddedSchedulerEvent(app.user, app.submissionContext, false,
+                app.applicationPriority, placementContext));
         return RMAppState.SUBMITTED;
       }
 
       // Add application to scheduler synchronously to guarantee scheduler
       // knows applications before AM or NM re-registers.
-      app.scheduler.handle(new AppAddedSchedulerEvent(app.user,
-          app.submissionContext, true, app.applicationPriority));
+      app.scheduler.handle(
+          new AppAddedSchedulerEvent(app.user, app.submissionContext, true,
+              app.applicationPriority, placementContext));
 
       // recover attempts
       app.recoverAppAttempts();
@@ -1120,8 +1138,20 @@ private static final class AddApplicationToSchedulerTransition extends
       RMAppTransition {
     @Override
     public void transition(RMAppImpl app, RMAppEvent event) {
-      app.handler.handle(new AppAddedSchedulerEvent(app.user,
-          app.submissionContext, false, app.applicationPriority));
+      ApplicationPlacementContext placementContext = null;
+      try {
+        placementContext = placeApplication(app.rmContext,
+            app.submissionContext, app.user);
+        replaceQueueFromPlacementContext(placementContext,
+            app.submissionContext);
+      } catch (YarnException e) {
+        String msg = "Failed to place application to queue :" + e.getMessage();
+        app.diagnostics.append(msg);
+        LOG.error(msg, e);
+      }
+      app.handler.handle(
+          new AppAddedSchedulerEvent(app.user, app.submissionContext, false,
+              app.applicationPriority, placementContext));
       // send the ATS create Event
       app.sendATSCreateEvent();
     }
@@ -2013,4 +2043,37 @@ private void clearUnusedFields() {
     this.submissionContext.setAMContainerSpec(null);
     this.submissionContext.setLogAggregationContext(null);
   }
+
+  @VisibleForTesting
+  static ApplicationPlacementContext placeApplication(RMContext rmContext,
+      ApplicationSubmissionContext context, String user) throws YarnException {
+
+    ApplicationPlacementContext placementContext = null;
+    PlacementManager placementManager = rmContext.getQueuePlacementManager();
+
+    if (placementManager != null) {
+      placementContext = placementManager.placeApplication(context, user);
+    } else{
+      LOG.error(
+          "Queue Placement Manager is null. Cannot place application :" + " "
+              + context.getApplicationId() + " to queue ");
+    }
+
+    return placementContext;
+  }
+
+  static void replaceQueueFromPlacementContext(
+      ApplicationPlacementContext placementContext,
+      ApplicationSubmissionContext context) {
+    // Set it to ApplicationSubmissionContext
+    //apply queue mapping only to new application submissions
+    if (placementContext != null && !StringUtils.equals(context.getQueue(),
+        placementContext.getQueue())) {
+      LOG.info("Placed application=" + context.getApplicationId() + " to queue="
+          + placementContext.getQueue() + ", original queue=" + context
+          .getQueue());
+      context.setQueue(placementContext.getQueue());
+    }
+  }
+
 }

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/scheduler/capacity/AbstractCSQueue.java

@@ -78,7 +78,7 @@ public abstract class AbstractCSQueue implements CSQueue {
   final String queueName;
   private final String queuePath;
   volatile int numContainers;
-  
+
   final Resource minimumAllocation;
   volatile Resource maximumAllocation;
   private volatile QueueState state = null;

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/scheduler/capacity/AbstractManagedParentQueue.java

@@ -35,31 +35,13 @@ public abstract class AbstractManagedParentQueue extends ParentQueue {
   private static final Logger LOG = LoggerFactory.getLogger(
       AbstractManagedParentQueue.class);
 
-  private int maxAppsForAutoCreatedQueues;
-  private int maxAppsPerUserForAutoCreatedQueues;
-  private int userLimit;
-  private float userLimitFactor;
+  protected AutoCreatedLeafQueueTemplate leafQueueTemplate;
 
   public AbstractManagedParentQueue(CapacitySchedulerContext cs,
       String queueName, CSQueue parent, CSQueue old) throws IOException {
     super(cs, queueName, parent, old);
 
     super.setupQueueConfigs(csContext.getClusterResource());
-    initializeLeafQueueConfigs();
-
-    StringBuffer queueInfo = new StringBuffer();
-    queueInfo.append("Created Managed Parent Queue: ").append(queueName)
-        .append("\nof type : [" + getClass())
-        .append("]\nwith capacity: [")
-        .append(super.getCapacity()).append("]\nwith max capacity: [")
-        .append(super.getMaximumCapacity()).append("\nwith max apps: [")
-        .append(getMaxApplicationsForAutoCreatedQueues())
-        .append("]\nwith max apps per user: [")
-        .append(getMaxApplicationsPerUserForAutoCreatedQueues())
-        .append("]\nwith user limit: [").append(getUserLimit())
-        .append("]\nwith user limit factor: [")
-        .append(getUserLimitFactor()).append("].");
-    LOG.info(queueInfo.toString());
   }
 
   @Override
@@ -71,8 +53,6 @@ public void reinitialize(CSQueue newlyParsedQueue, Resource clusterResource)
       // Set new configs
       setupQueueConfigs(clusterResource);
 
-      initializeLeafQueueConfigs();
-
       // run reinitialize on each existing queue, to trigger absolute cap
       // recomputations
       for (CSQueue res : this.getChildQueues()) {
@@ -87,72 +67,29 @@ public void reinitialize(CSQueue newlyParsedQueue, Resource clusterResource)
    * Initialize leaf queue configs from template configurations specified on
    * parent queue.
    */
-  protected void initializeLeafQueueConfigs() {
+  protected AutoCreatedLeafQueueTemplate.Builder initializeLeafQueueConfigs
+    (String queuePath) {
 
     CapacitySchedulerConfiguration conf = csContext.getConfiguration();
 
-    final String queuePath = super.getQueuePath();
+    AutoCreatedLeafQueueTemplate.Builder leafQueueTemplateBuilder = new
+        AutoCreatedLeafQueueTemplate.Builder();
     int maxApps = conf.getMaximumApplicationsPerQueue(queuePath);
     if (maxApps < 0) {
       maxApps = (int) (
           CapacitySchedulerConfiguration.DEFAULT_MAXIMUM_SYSTEM_APPLICATIIONS
               * getAbsoluteCapacity());
     }
-    userLimit = conf.getUserLimit(queuePath);
-    userLimitFactor = conf.getUserLimitFactor(queuePath);
-    maxAppsForAutoCreatedQueues = maxApps;
-    maxAppsPerUserForAutoCreatedQueues =
-        (int) (maxApps * (userLimit / 100.0f) * userLimitFactor);
 
-  }
+    int userLimit = conf.getUserLimit(queuePath);
+    float userLimitFactor = conf.getUserLimitFactor(queuePath);
+    leafQueueTemplateBuilder.userLimit(userLimit)
+          .userLimitFactor(userLimitFactor)
+          .maxApps(maxApps)
+          .maxAppsPerUser(
+              (int) (maxApps * (userLimit / 100.0f) * userLimitFactor));
 
-  /**
-   * Number of maximum applications for each of the auto created leaf queues.
-   *
-   * @return maxAppsForAutoCreatedQueues
-   */
-  public int getMaxApplicationsForAutoCreatedQueues() {
-    return maxAppsForAutoCreatedQueues;
-  }
-
-  /**
-   * Number of maximum applications per user for each of the auto created
-   * leaf queues.
-   *
-   * @return maxAppsPerUserForAutoCreatedQueues
-   */
-  public int getMaxApplicationsPerUserForAutoCreatedQueues() {
-    return maxAppsPerUserForAutoCreatedQueues;
-  }
-
-  /**
-   * User limit value for each of the  auto created leaf queues.
-   *
-   * @return userLimit
-   */
-  public int getUserLimitForAutoCreatedQueues() {
-    return userLimit;
-  }
-
-  /**
-   * User limit factor value for each of the  auto created leaf queues.
-   *
-   * @return userLimitFactor
-   */
-  public float getUserLimitFactor() {
-    return userLimitFactor;
-  }
-
-  public int getMaxAppsForAutoCreatedQueues() {
-    return maxAppsForAutoCreatedQueues;
-  }
-
-  public int getMaxAppsPerUserForAutoCreatedQueues() {
-    return maxAppsPerUserForAutoCreatedQueues;
-  }
-
-  public int getUserLimit() {
-    return userLimit;
+    return leafQueueTemplateBuilder;
   }
 
   /**
@@ -229,4 +166,111 @@ public CSQueue removeChildQueue(String childQueueName)
     }
     return childQueue;
   }
+
+  protected float sumOfChildCapacities() {
+    try {
+      writeLock.lock();
+      float ret = 0;
+      for (CSQueue l : childQueues) {
+        ret += l.getCapacity();
+      }
+      return ret;
+    } finally {
+      writeLock.unlock();
+    }
+  }
+
+  protected float sumOfChildAbsCapacities() {
+    try {
+      writeLock.lock();
+      float ret = 0;
+      for (CSQueue l : childQueues) {
+        ret += l.getAbsoluteCapacity();
+      }
+      return ret;
+    } finally {
+      writeLock.unlock();
+    }
+  }
+
+  public static class AutoCreatedLeafQueueTemplate {
+
+    private QueueCapacities queueCapacities;
+
+    private int maxApps;
+    private int maxAppsPerUser;
+    private int userLimit;
+    private float userLimitFactor;
+
+    AutoCreatedLeafQueueTemplate(Builder builder) {
+      this.maxApps = builder.maxApps;
+      this.maxAppsPerUser = builder.maxAppsPerUser;
+      this.userLimit = builder.userLimit;
+      this.userLimitFactor = builder.userLimitFactor;
+      this.queueCapacities = builder.queueCapacities;
+    }
+
+    public static class Builder {
+      private int maxApps;
+      private int maxAppsPerUser;
+
+      private int userLimit;
+      private float userLimitFactor;
+
+      private QueueCapacities queueCapacities;
+
+      Builder maxApps(int maxApplications) {
+        this.maxApps =  maxApplications;
+        return this;
+      }
+
+      Builder maxAppsPerUser(int maxApplicationsPerUser) {
+        this.maxAppsPerUser = maxApplicationsPerUser;
+        return this;
+      }
+
+      Builder userLimit(int usrLimit) {
+        this.userLimit = usrLimit;
+        return this;
+      }
+
+      Builder userLimitFactor(float ulf) {
+        this.userLimitFactor = ulf;
+        return this;
+      }
+
+      Builder capacities(QueueCapacities capacities) {
+        this.queueCapacities = capacities;
+        return this;
+      }
+
+      AutoCreatedLeafQueueTemplate build() {
+        return new AutoCreatedLeafQueueTemplate(this);
+      }
+    }
+
+    public int getUserLimit() {
+      return userLimit;
+    }
+
+    public float getUserLimitFactor() {
+      return userLimitFactor;
+    }
+
+    public QueueCapacities getQueueCapacities() {
+      return queueCapacities;
+    }
+
+    public int getMaxApps() {
+      return maxApps;
+    }
+
+    public int getMaxAppsPerUser() {
+      return maxAppsPerUser;
+    }
+  }
+
+  public AutoCreatedLeafQueueTemplate getLeafQueueTemplate() {
+    return leafQueueTemplate;
+  }
 }

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/scheduler/capacity/AutoCreatedLeafQueue.java

@@ -21,6 +21,8 @@
 import org.apache.hadoop.yarn.api.records.Resource;
 import org.apache.hadoop.yarn.server.resourcemanager.scheduler.SchedulerDynamicEditException;
 import org.apache.hadoop.yarn.server.resourcemanager.scheduler.common.QueueEntitlement;
+import org.apache.hadoop.yarn.server.resourcemanager.scheduler.capacity
+    .AbstractManagedParentQueue.AutoCreatedLeafQueueTemplate;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -42,17 +44,18 @@ public AutoCreatedLeafQueue(CapacitySchedulerContext cs, String queueName,
       AbstractManagedParentQueue parent) throws IOException {
     super(cs, queueName, parent, null);
 
-    updateApplicationAndUserLimits(parent.getUserLimitForAutoCreatedQueues(),
-        parent.getUserLimitFactor(),
-        parent.getMaxApplicationsForAutoCreatedQueues(),
-        parent.getMaxApplicationsPerUserForAutoCreatedQueues());
-
+    AutoCreatedLeafQueueTemplate leafQueueTemplate =
+        parent.getLeafQueueTemplate();
+    updateApplicationAndUserLimits(leafQueueTemplate.getUserLimit(),
+        leafQueueTemplate.getUserLimitFactor(),
+        leafQueueTemplate.getMaxApps(),
+        leafQueueTemplate.getMaxAppsPerUser());
     this.parent = parent;
   }
 
   @Override
-  public void reinitialize(CSQueue newlyParsedQueue,
-      Resource clusterResource) throws IOException {
+  public void reinitialize(CSQueue newlyParsedQueue, Resource clusterResource)
+      throws IOException {
     try {
       writeLock.lock();
 
@@ -62,10 +65,12 @@ public void reinitialize(CSQueue newlyParsedQueue,
       CSQueueUtils.updateQueueStatistics(resourceCalculator, clusterResource,
           this, labelManager, null);
 
-      updateApplicationAndUserLimits(parent.getUserLimitForAutoCreatedQueues(),
-          parent.getUserLimitFactor(),
-          parent.getMaxApplicationsForAutoCreatedQueues(),
-          parent.getMaxApplicationsPerUserForAutoCreatedQueues());
+      AutoCreatedLeafQueueTemplate leafQueueTemplate =
+          parent.getLeafQueueTemplate();
+      updateApplicationAndUserLimits(leafQueueTemplate.getUserLimit(),
+          leafQueueTemplate.getUserLimitFactor(),
+          leafQueueTemplate.getMaxApps(),
+          leafQueueTemplate.getMaxAppsPerUser());
 
     } finally {
       writeLock.unlock();

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/scheduler/capacity/CapacityScheduler.java

@@ -41,7 +41,6 @@
 import org.apache.hadoop.conf.Configurable;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.security.AccessControlException;
-import org.apache.hadoop.security.Groups;
 import org.apache.hadoop.security.UserGroupInformation;
 import org.apache.hadoop.util.Time;
 import org.apache.hadoop.yarn.api.records.ApplicationAttemptId;
@@ -64,10 +63,10 @@
 import org.apache.hadoop.yarn.proto.YarnServiceProtos.SchedulerResourceTypes;
 import org.apache.hadoop.yarn.server.resourcemanager.RMContext;
 import org.apache.hadoop.yarn.server.resourcemanager.nodelabels.RMNodeLabelsManager;
+import org.apache.hadoop.yarn.server.resourcemanager.placement.ApplicationPlacementContext;
 import org.apache.hadoop.yarn.server.resourcemanager.placement.PlacementFactory;
 import org.apache.hadoop.yarn.server.resourcemanager.placement.PlacementRule;
 import org.apache.hadoop.yarn.server.resourcemanager.placement.UserGroupMappingPlacementRule;
-import org.apache.hadoop.yarn.server.resourcemanager.placement.UserGroupMappingPlacementRule.QueueMapping;
 import org.apache.hadoop.yarn.server.resourcemanager.recovery.RMStateStore.RMState;
 import org.apache.hadoop.yarn.server.resourcemanager.recovery.records.ApplicationStateData;
 import org.apache.hadoop.yarn.server.resourcemanager.reservation.ReservationConstants;
@@ -146,6 +145,8 @@
 import com.google.common.base.Preconditions;
 import com.google.common.util.concurrent.SettableFuture;
 
+import static org.apache.hadoop.yarn.server.resourcemanager.scheduler.capacity.CapacitySchedulerConfiguration.QUEUE_MAPPING;
+
 @LimitedPrivate("yarn")
 @Evolving
 @SuppressWarnings("unchecked")
@@ -560,44 +561,17 @@ public int getPendingBacklogs() {
   }
 
   @VisibleForTesting
-  public UserGroupMappingPlacementRule
-      getUserGroupMappingPlacementRule() throws IOException {
+  public PlacementRule getUserGroupMappingPlacementRule() throws IOException {
     try {
       readLock.lock();
-      boolean overrideWithQueueMappings = conf.getOverrideWithQueueMappings();
-      LOG.info(
-          "Initialized queue mappings, override: " + overrideWithQueueMappings);
-
-      // Get new user/group mappings
-      List<QueueMapping> newMappings = conf.getQueueMappings();
-      // check if mappings refer to valid queues
-      for (QueueMapping mapping : newMappings) {
-        String mappingQueue = mapping.getQueue();
-        if (!mappingQueue.equals(
-            UserGroupMappingPlacementRule.CURRENT_USER_MAPPING) && !mappingQueue
-            .equals(UserGroupMappingPlacementRule.PRIMARY_GROUP_MAPPING)) {
-          CSQueue queue = getQueue(mappingQueue);
-          if (queue == null || !(queue instanceof LeafQueue)) {
-            throw new IOException(
-                "mapping contains invalid or non-leaf queue " + mappingQueue);
-          }
-        }
-      }
-
-      // initialize groups if mappings are present
-      if (newMappings.size() > 0) {
-        Groups groups = new Groups(conf);
-        return new UserGroupMappingPlacementRule(overrideWithQueueMappings,
-            newMappings, groups);
-      }
-
-      return null;
+      return UserGroupMappingPlacementRule.get(this);
     } finally {
       readLock.unlock();
     }
   }
 
-  private void updatePlacementRules() throws IOException {
+  @VisibleForTesting
+  void updatePlacementRules() throws IOException {
     // Initialize placement rules
     Collection<String> placementRuleStrs = conf.getStringCollection(
         YarnConfiguration.QUEUE_PLACEMENT_RULES);
@@ -731,37 +705,92 @@ private void addApplicationOnRecovery(
     }
   }
 
-  private void addApplication(ApplicationId applicationId,
-      String queueName, String user, Priority priority) {
+  private void addApplication(ApplicationId applicationId, String queueName,
+      String user, Priority priority,
+      ApplicationPlacementContext placementContext) {
     try {
       writeLock.lock();
       if (isSystemAppsLimitReached()) {
         String message = "Maximum system application limit reached,"
             + "cannot accept submission of application: " + applicationId;
-        this.rmContext.getDispatcher().getEventHandler().handle(new RMAppEvent(
-            applicationId, RMAppEventType.APP_REJECTED, message));
+        this.rmContext.getDispatcher().getEventHandler().handle(
+            new RMAppEvent(applicationId, RMAppEventType.APP_REJECTED,
+                message));
         return;
       }
       // Sanity checks.
       CSQueue queue = getQueue(queueName);
+
+      if (queue == null && placementContext != null) {
+        //Could be a potential auto-created leaf queue
+        try {
+          queue = autoCreateLeafQueue(placementContext);
+        } catch (YarnException | IOException e) {
+          LOG.error("Could not auto-create leaf queue due to : ", e);
+          final String message =
+              "Application " + applicationId + " submission by user : " + user
+                  + " to  queue : " + queueName + " failed : " + e.getMessage();
+          this.rmContext.getDispatcher().getEventHandler().handle(
+              new RMAppEvent(applicationId, RMAppEventType.APP_REJECTED,
+                  message));
+        }
+      }
+
       if (queue == null) {
-        String message =
+        final String message =
             "Application " + applicationId + " submitted by user " + user
                 + " to unknown queue: " + queueName;
+
         this.rmContext.getDispatcher().getEventHandler().handle(
             new RMAppEvent(applicationId, RMAppEventType.APP_REJECTED,
                 message));
         return;
       }
+
       if (!(queue instanceof LeafQueue)) {
         String message =
-            "Application " + applicationId + " submitted by user " + user
-                + " to non-leaf queue: " + queueName;
+            "Application " + applicationId + " submitted by user : " + user
+                + " to non-leaf queue : " + queueName;
         this.rmContext.getDispatcher().getEventHandler().handle(
             new RMAppEvent(applicationId, RMAppEventType.APP_REJECTED,
                 message));
         return;
+      } else if (queue instanceof AutoCreatedLeafQueue && queue
+          .getParent() instanceof ManagedParentQueue) {
+
+        //If queue already exists and auto-queue creation was not required,
+        //placement context should not be null
+        if (placementContext == null) {
+          String message =
+              "Application " + applicationId + " submission by user : " + user
+                  + " to specified queue : " + queueName + "  is prohibited. "
+                  + "Verify automatic queue mapping for user exists in " +
+                  QUEUE_MAPPING;
+          this.rmContext.getDispatcher().getEventHandler().handle(
+              new RMAppEvent(applicationId, RMAppEventType.APP_REJECTED,
+                  message));
+          return;
+          // For a queue which exists already and
+          // not auto-created above, then its parent queue should match
+          // the parent queue specified in queue mapping
+        } else if (!queue.getParent().getQueueName().equals(
+            placementContext.getParentQueue())) {
+          String message =
+              "Auto created Leaf queue " + placementContext.getQueue() + " "
+                  + "already exists under queue : " + queue
+                  .getParent().getQueuePath()
+                  + ".But Queue mapping configuration " +
+                   CapacitySchedulerConfiguration.QUEUE_MAPPING + " has been "
+                  + "updated to a different parent queue : "
+                  + placementContext.getParentQueue()
+                  + " for the specified user : " + user;
+          this.rmContext.getDispatcher().getEventHandler().handle(
+              new RMAppEvent(applicationId, RMAppEventType.APP_REJECTED,
+                  message));
+          return;
+        }
       }
+
       // Submit to the queue
       try {
         queue.submitApplication(applicationId, user, queueName);
@@ -1483,7 +1512,8 @@ public void handle(SchedulerEvent event) {
       if (queueName != null) {
         if (!appAddedEvent.getIsAppRecovering()) {
           addApplication(appAddedEvent.getApplicationId(), queueName,
-              appAddedEvent.getUser(), appAddedEvent.getApplicatonPriority());
+              appAddedEvent.getUser(), appAddedEvent.getApplicatonPriority(),
+              appAddedEvent.getPlacementContext());
         } else {
           addApplicationOnRecovery(appAddedEvent.getApplicationId(), queueName,
               appAddedEvent.getUser(), appAddedEvent.getApplicatonPriority());
@@ -2001,7 +2031,8 @@ public void setEntitlement(String inQueue, QueueEntitlement entitlement)
     try {
       writeLock.lock();
       LeafQueue queue = this.queueManager.getAndCheckLeafQueue(inQueue);
-      ParentQueue parent = (ParentQueue) queue.getParent();
+      AbstractManagedParentQueue parent = (AbstractManagedParentQueue) queue
+          .getParent();
 
       if (!(queue instanceof AutoCreatedLeafQueue)) {
         throw new SchedulerDynamicEditException(
@@ -2010,7 +2041,8 @@ public void setEntitlement(String inQueue, QueueEntitlement entitlement)
       }
 
       if (parent == null
-          || !(AbstractManagedParentQueue.class.isAssignableFrom(parent.getClass()))) {
+          || !(AbstractManagedParentQueue.class.isAssignableFrom(
+              parent.getClass()))) {
         throw new SchedulerDynamicEditException(
             "The parent of AutoCreatedLeafQueue " + inQueue
                 + " must be a PlanQueue/ManagedParentQueue");
@@ -2655,4 +2687,43 @@ public MutableConfigurationProvider getMutableConfProvider() {
     }
     return null;
   }
+
+  private LeafQueue autoCreateLeafQueue(
+      ApplicationPlacementContext placementContext)
+      throws IOException, YarnException {
+
+    AutoCreatedLeafQueue autoCreatedLeafQueue = null;
+
+    String leafQueueName = placementContext.getQueue();
+    String parentQueueName = placementContext.getParentQueue();
+
+    if (!StringUtils.isEmpty(parentQueueName)) {
+      CSQueue parentQueue = getQueue(parentQueueName);
+
+      if (parentQueue != null && conf.isAutoCreateChildQueueEnabled(
+          parentQueue.getQueuePath())) {
+
+        ManagedParentQueue autoCreateEnabledParentQueue =
+            (ManagedParentQueue) parentQueue;
+        autoCreatedLeafQueue = new AutoCreatedLeafQueue(this, leafQueueName,
+            autoCreateEnabledParentQueue);
+
+        addQueue(autoCreatedLeafQueue);
+
+        //TODO - Set entitlement through capacity management policy
+      } else{
+        throw new SchedulerDynamicEditException(
+            "Could not auto-create leaf queue for " + leafQueueName
+                + ". Queue mapping specifies an invalid parent queue "
+                + "which does not exist "
+                + parentQueueName);
+      }
+    } else{
+      throw new SchedulerDynamicEditException(
+          "Could not auto-create leaf queue for " + leafQueueName
+              + ". Queue mapping does not specify"
+              + " which parent queue it needs to be created under.");
+    }
+    return autoCreatedLeafQueue;
+  }
 }

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/scheduler/capacity/CapacitySchedulerConfiguration.java

@@ -907,6 +907,12 @@ public boolean getOverrideWithQueueMappings() {
         DEFAULT_ENABLE_QUEUE_MAPPING_OVERRIDE);
   }
 
+  @Private
+  @VisibleForTesting
+  public void setOverrideWithQueueMappings(boolean overrideWithQueueMappings) {
+    setBoolean(ENABLE_QUEUE_MAPPING_OVERRIDE, overrideWithQueueMappings);
+  }
+
   /**
    * Returns a collection of strings, trimming leading and trailing whitespeace
    * on each value
@@ -981,6 +987,31 @@ public List<QueueMapping> getQueueMappings() {
     return mappings;
   }
 
+  @Private
+  @VisibleForTesting
+  public void setQueuePlacementRules(Collection<String> queuePlacementRules) {
+    if (queuePlacementRules == null) {
+      return;
+    }
+    String str = StringUtils.join(",", queuePlacementRules);
+    setStrings(YarnConfiguration.QUEUE_PLACEMENT_RULES, str);
+  }
+
+  @Private
+  @VisibleForTesting
+  public void setQueueMappings(List<QueueMapping> queueMappings) {
+    if (queueMappings == null) {
+      return;
+    }
+
+    List<String> queueMappingStrs = new ArrayList<>();
+    for (QueueMapping mapping : queueMappings) {
+      queueMappingStrs.add(mapping.toString());
+    }
+
+    setStrings(QUEUE_MAPPING, StringUtils.join(",", queueMappingStrs));
+  }
+
   public boolean isReservable(String queue) {
     boolean isReservable =
         getBoolean(getQueuePrefix(queue) + IS_RESERVABLE, false);
@@ -1523,4 +1554,126 @@ public long getDefaultLifetimePerQueue(String queue) {
   public void setDefaultLifetimePerQueue(String queue, long defaultLifetime) {
     setLong(getQueuePrefix(queue) + DEFAULT_LIFETIME_SUFFIX, defaultLifetime);
   }
+
+  @Private
+  public static final boolean DEFAULT_AUTO_CREATE_CHILD_QUEUE_ENABLED = false;
+
+  @Private
+  public static final String AUTO_CREATE_CHILD_QUEUE_ENABLED =
+      "auto-create-child-queue.enabled";
+
+  @Private
+  public static final String AUTO_CREATED_LEAF_QUEUE_TEMPLATE_PREFIX =
+      "leaf-queue-template";
+
+  @Private
+  public static final String AUTO_CREATE_QUEUE_MAX_QUEUES =
+      "auto-create-child-queue.max-queues";
+
+  @Private
+  public static final int DEFAULT_AUTO_CREATE_QUEUE_MAX_QUEUES = 1000;
+
+  /**
+   * If true, this queue will be created as a Parent Queue which Auto Created
+   * leaf child queues
+   *
+   * @param queuePath The queues path
+   * @return true if auto create is enabled for child queues else false. Default
+   * is false
+   */
+  @Private
+  public boolean isAutoCreateChildQueueEnabled(String queuePath) {
+    boolean isAutoCreateEnabled = getBoolean(
+        getQueuePrefix(queuePath) + AUTO_CREATE_CHILD_QUEUE_ENABLED,
+        DEFAULT_AUTO_CREATE_CHILD_QUEUE_ENABLED);
+    return isAutoCreateEnabled;
+  }
+
+  @Private
+  @VisibleForTesting
+  public void setAutoCreateChildQueueEnabled(String queuePath,
+      boolean autoCreationEnabled) {
+    setBoolean(getQueuePrefix(queuePath) +
+            AUTO_CREATE_CHILD_QUEUE_ENABLED,
+        autoCreationEnabled);
+  }
+
+  /**
+   * Get the auto created leaf queue's template configuration prefix
+   * Leaf queue's template capacities are configured at the parent queue
+   *
+   * @param queuePath parent queue's path
+   * @return Config prefix for leaf queue template configurations
+   */
+  @Private
+  public String getAutoCreatedQueueTemplateConfPrefix(String queuePath) {
+    return queuePath + DOT + AUTO_CREATED_LEAF_QUEUE_TEMPLATE_PREFIX;
+  }
+
+  @Private
+  public static final String FAIL_AUTO_CREATION_ON_EXCEEDING_CAPACITY =
+      "auto-create-child-queue.fail-on-exceeding-parent-capacity";
+
+  @Private
+  public static final boolean DEFAULT_FAIL_AUTO_CREATION_ON_EXCEEDING_CAPACITY =
+      false;
+
+  /**
+   * Fail further auto leaf queue creation when parent's guaranteed capacity is
+   * exceeded.
+   *
+   * @param queuePath the parent queue's path
+   * @return true if configured to fail else false
+   */
+  @Private
+  public boolean getShouldFailAutoQueueCreationWhenGuaranteedCapacityExceeded(
+      String queuePath) {
+    boolean shouldFailAutoQueueCreationOnExceedingGuaranteedCapacity =
+        getBoolean(getQueuePrefix(queuePath)
+                + FAIL_AUTO_CREATION_ON_EXCEEDING_CAPACITY,
+            DEFAULT_FAIL_AUTO_CREATION_ON_EXCEEDING_CAPACITY);
+    return shouldFailAutoQueueCreationOnExceedingGuaranteedCapacity;
+  }
+
+  @VisibleForTesting
+  @Private
+  public void setShouldFailAutoQueueCreationWhenGuaranteedCapacityExceeded(
+      String queuePath, boolean autoCreationEnabled) {
+    setBoolean(
+        getQueuePrefix(queuePath) +
+            FAIL_AUTO_CREATION_ON_EXCEEDING_CAPACITY,
+        autoCreationEnabled);
+  }
+
+  /**
+   * Get the max number of leaf queues that are allowed to be created under
+   * a parent queue
+   *
+   * @param queuePath the paret queue's path
+   * @return the max number of leaf queues allowed to be auto created
+   */
+  @Private
+  public int getAutoCreatedQueuesMaxChildQueuesLimit(String queuePath) {
+    return getInt(getQueuePrefix(queuePath) +
+            AUTO_CREATE_QUEUE_MAX_QUEUES,
+        DEFAULT_AUTO_CREATE_QUEUE_MAX_QUEUES);
+  }
+
+  @Private
+  @VisibleForTesting
+  public void setAutoCreatedLeafQueueTemplateCapacity(String queuePath,
+      float val) {
+    String leafQueueConfPrefix = getAutoCreatedQueueTemplateConfPrefix(
+        queuePath);
+    setCapacity(leafQueueConfPrefix, val);
+  }
+
+  @Private
+  @VisibleForTesting
+  public void setAutoCreatedLeafQueueTemplateMaxCapacity(String queuePath,
+      float val) {
+    String leafQueueConfPrefix = getAutoCreatedQueueTemplateConfPrefix(
+        queuePath);
+    setMaximumCapacity(leafQueueConfPrefix, val);
+  }
 }

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/scheduler/capacity/CapacitySchedulerQueueManager.java

@@ -154,7 +154,7 @@ public void setCapacitySchedulerContext(
    * @throws IOException if fails to initialize queues
    */
   public void initializeQueues(CapacitySchedulerConfiguration conf)
-      throws IOException {
+    throws IOException {
     root = parseQueue(this.csContext, conf, null,
         CapacitySchedulerConfiguration.ROOT, queues, queues, NOOP);
     setQueueAcls(authorizer, appPriorityACLManager, queues);
@@ -176,7 +176,7 @@ public void reinitializeQueues(CapacitySchedulerConfiguration newConf)
     if (!csContext.isConfigurationMutable() ||
         csContext.getRMContext().getHAServiceState()
             != HAServiceProtocol.HAServiceState.STANDBY) {
-      // Ensure queue hiearchy in the new XML file is proper.
+      // Ensure queue hierarchy in the new XML file is proper.
       validateQueueHierarchy(queues, newQueues);
     }
 
@@ -216,11 +216,13 @@ static CSQueue parseQueue(
       Map<String, CSQueue> oldQueues,
       QueueHook hook) throws IOException {
     CSQueue queue;
-    String fullQueueName =
-        (parent == null) ? queueName
-            : (parent.getQueuePath() + "." + queueName);
+    String fullQueueName = (parent == null) ?
+        queueName :
+        (parent.getQueuePath() + "." + queueName);
     String[] childQueueNames = conf.getQueues(fullQueueName);
     boolean isReservableQueue = conf.isReservable(fullQueueName);
+    boolean isAutoCreateEnabled = conf.isAutoCreateChildQueueEnabled(
+        fullQueueName);
     if (childQueueNames == null || childQueueNames.length == 0) {
       if (null == parent) {
         throw new IllegalStateException(
@@ -229,9 +231,8 @@ static CSQueue parseQueue(
       // Check if the queue will be dynamically managed by the Reservation
       // system
       if (isReservableQueue) {
-        queue =
-            new PlanQueue(csContext, queueName, parent,
-                oldQueues.get(queueName));
+        queue = new PlanQueue(csContext, queueName, parent,
+            oldQueues.get(queueName));
 
         //initializing the "internal" default queue, for SLS compatibility
         String defReservationId =
@@ -249,38 +250,46 @@ static CSQueue parseQueue(
         ((PlanQueue) queue).setChildQueues(childQueues);
         queues.put(defReservationId, resQueue);
 
-      } else {
-        queue =
-            new LeafQueue(csContext, queueName, parent,
-                oldQueues.get(queueName));
+      } else if (isAutoCreateEnabled) {
+        queue = new ManagedParentQueue(csContext, queueName, parent,
+            oldQueues.get(queueName));
 
+      } else{
+        queue = new LeafQueue(csContext, queueName, parent,
+            oldQueues.get(queueName));
         // Used only for unit tests
         queue = hook.hook(queue);
       }
-    } else {
+    } else{
       if (isReservableQueue) {
         throw new IllegalStateException(
             "Only Leaf Queues can be reservable for " + queueName);
       }
-      ParentQueue parentQueue =
-          new ParentQueue(csContext, queueName, parent,
-              oldQueues.get(queueName));
+
+      ParentQueue parentQueue;
+      if (isAutoCreateEnabled) {
+        parentQueue = new ManagedParentQueue(csContext, queueName, parent,
+            oldQueues.get(queueName));
+      } else{
+        parentQueue = new ParentQueue(csContext, queueName, parent,
+            oldQueues.get(queueName));
+      }
 
       // Used only for unit tests
       queue = hook.hook(parentQueue);
 
       List<CSQueue> childQueues = new ArrayList<>();
       for (String childQueueName : childQueueNames) {
-        CSQueue childQueue =
-            parseQueue(csContext, conf, queue, childQueueName,
-              queues, oldQueues, hook);
+        CSQueue childQueue = parseQueue(csContext, conf, queue, childQueueName,
+            queues, oldQueues, hook);
         childQueues.add(childQueue);
       }
       parentQueue.setChildQueues(childQueues);
+
     }
 
-    if (queue instanceof LeafQueue && queues.containsKey(queueName)
-        && queues.get(queueName) instanceof LeafQueue) {
+    if (queue instanceof LeafQueue && queues.containsKey(queueName) && queues
+        .get(queueName) instanceof LeafQueue) {
       throw new IOException("Two leaf queues were named " + queueName
           + ". Leaf queue names must be distinct");
     }
@@ -312,27 +321,46 @@ private void validateQueueHierarchy(Map<String, CSQueue> queues,
           if (oldQueue.getState() == QueueState.STOPPED) {
             LOG.info("Deleting Queue " + queueName + ", as it is not"
                 + " present in the modified capacity configuration xml");
-          } else {
+          } else{
             throw new IOException(oldQueue.getQueuePath() + " is deleted from"
                 + " the new capacity scheduler configuration, but the"
-                + " queue is not yet in stopped state. "
-                + "Current State : " + oldQueue.getState());
+                + " queue is not yet in stopped state. " + "Current State : "
+                + oldQueue.getState());
           }
         } else if (!oldQueue.getQueuePath().equals(newQueue.getQueuePath())) {
           //Queue's cannot be moved from one hierarchy to other
-          throw new IOException(queueName + " is moved from:"
-              + oldQueue.getQueuePath() + " to:" + newQueue.getQueuePath()
-              + " after refresh, which is not allowed.");
-        } else  if (oldQueue instanceof LeafQueue
+          throw new IOException(
+              queueName + " is moved from:" + oldQueue.getQueuePath() + " to:"
+                  + newQueue.getQueuePath()
+                  + " after refresh, which is not allowed.");
+        } else if (oldQueue instanceof ParentQueue
+            && !(oldQueue instanceof ManagedParentQueue)
+            && newQueue instanceof ManagedParentQueue) {
+          throw new IOException(
+              "Can not convert parent queue: " + oldQueue.getQueuePath()
+                  + " to auto create enabled parent queue since "
+                  + "it could have other pre-configured queues which is not "
+                  + "supported");
+        } else if (oldQueue instanceof ManagedParentQueue
+            && !(newQueue instanceof ManagedParentQueue)) {
+          throw new IOException(
+              "Cannot convert auto create enabled parent queue: " + oldQueue
+                  .getQueuePath() + " to leaf queue. Please check "
+                  + " parent queue's configuration "
+                  + CapacitySchedulerConfiguration
+                  .AUTO_CREATE_CHILD_QUEUE_ENABLED
+                  + " is set to true");
+        } else if (oldQueue instanceof LeafQueue
             && newQueue instanceof ParentQueue) {
           if (oldQueue.getState() == QueueState.STOPPED) {
             LOG.info("Converting the leaf queue: " + oldQueue.getQueuePath()
                 + " to parent queue.");
-          } else {
-            throw new IOException("Can not convert the leaf queue: "
-                + oldQueue.getQueuePath() + " to parent queue since "
-                + "it is not yet in stopped state. Current State : "
-                + oldQueue.getState());
+          } else{
+            throw new IOException(
+                "Can not convert the leaf queue: " + oldQueue.getQueuePath()
+                    + " to parent queue since "
+                    + "it is not yet in stopped state. Current State : "
+                    + oldQueue.getState());
           }
         } else if (oldQueue instanceof ParentQueue
             && newQueue instanceof LeafQueue) {
@@ -352,6 +380,7 @@ private void validateQueueHierarchy(Map<String, CSQueue> queues,
    */
   private void updateQueues(Map<String, CSQueue> existingQueues,
       Map<String, CSQueue> newQueues) {
+    CapacitySchedulerConfiguration conf = csContext.getConfiguration();
     for (Map.Entry<String, CSQueue> e : newQueues.entrySet()) {
       String queueName = e.getKey();
       CSQueue queue = e.getValue();
@@ -363,7 +392,13 @@ private void updateQueues(Map<String, CSQueue> existingQueues,
         .iterator(); itr.hasNext();) {
       Map.Entry<String, CSQueue> e = itr.next();
       String queueName = e.getKey();
-      if (!newQueues.containsKey(queueName)) {
+      CSQueue existingQueue = e.getValue();
+
+      //TODO - Handle case when auto create is disabled on parent queues
+      if (!newQueues.containsKey(queueName) && !(
+          existingQueue instanceof AutoCreatedLeafQueue && conf
+              .isAutoCreateChildQueueEnabled(
+                  existingQueue.getParent().getQueuePath()))) {
         itr.remove();
       }
     }

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/scheduler/capacity/ManagedParentQueue.java

@@ -0,0 +1,158 @@
+/**
+ * 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
+ * <p>
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * <p>
+ * 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.scheduler.capacity;
+
+import org.apache.hadoop.yarn.api.records.Resource;
+import org.apache.hadoop.yarn.server.resourcemanager.scheduler
+    .SchedulerDynamicEditException;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.io.IOException;
+
+/**
+ * Auto Creation enabled Parent queue. This queue initially does not have any
+ * children to start with and all child
+ * leaf queues will be auto created. Currently this does not allow other
+ * pre-configured leaf or parent queues to
+ * co-exist along with auto-created leaf queues. The auto creation is limited
+ * to leaf queues currently.
+ */
+public class ManagedParentQueue extends AbstractManagedParentQueue {
+
+  private boolean shouldFailAutoCreationWhenGuaranteedCapacityExceeded = false;
+
+  private static final Logger LOG = LoggerFactory.getLogger(
+      ManagedParentQueue.class);
+
+  public ManagedParentQueue(final CapacitySchedulerContext cs,
+      final String queueName, final CSQueue parent, final CSQueue old)
+      throws IOException {
+    super(cs, queueName, parent, old);
+    String leafQueueTemplateConfPrefix = getLeafQueueConfigPrefix(
+        csContext.getConfiguration());
+    this.leafQueueTemplate = initializeLeafQueueConfigs(
+        leafQueueTemplateConfPrefix).build();
+
+    StringBuffer queueInfo = new StringBuffer();
+    queueInfo.append("Created Managed Parent Queue: ").append(queueName).append(
+        "]\nwith capacity: [").append(super.getCapacity()).append(
+        "]\nwith max capacity: [").append(super.getMaximumCapacity()).append(
+        "\nwith max apps: [").append(leafQueueTemplate.getMaxApps()).append(
+        "]\nwith max apps per user: [").append(
+        leafQueueTemplate.getMaxAppsPerUser()).append("]\nwith user limit: [")
+        .append(leafQueueTemplate.getUserLimit()).append(
+        "]\nwith user limit factor: [").append(
+        leafQueueTemplate.getUserLimitFactor()).append("].");
+    LOG.info(queueInfo.toString());
+  }
+
+  @Override
+  public void reinitialize(CSQueue newlyParsedQueue, Resource clusterResource)
+      throws IOException {
+    validate(newlyParsedQueue);
+    super.reinitialize(newlyParsedQueue, clusterResource);
+    String leafQueueTemplateConfPrefix = getLeafQueueConfigPrefix(
+        csContext.getConfiguration());
+    this.leafQueueTemplate = initializeLeafQueueConfigs(
+        leafQueueTemplateConfPrefix).build();
+  }
+
+  @Override
+  protected AutoCreatedLeafQueueTemplate.Builder initializeLeafQueueConfigs(
+      String queuePath) {
+
+    AutoCreatedLeafQueueTemplate.Builder leafQueueTemplate =
+        super.initializeLeafQueueConfigs(queuePath);
+
+    CapacitySchedulerConfiguration conf = csContext.getConfiguration();
+    String leafQueueTemplateConfPrefix = getLeafQueueConfigPrefix(conf);
+    QueueCapacities queueCapacities = new QueueCapacities(false);
+    CSQueueUtils.loadUpdateAndCheckCapacities(leafQueueTemplateConfPrefix,
+        csContext.getConfiguration(), queueCapacities, getQueueCapacities());
+    leafQueueTemplate.capacities(queueCapacities);
+
+    shouldFailAutoCreationWhenGuaranteedCapacityExceeded =
+        conf.getShouldFailAutoQueueCreationWhenGuaranteedCapacityExceeded(
+            getQueuePath());
+
+    return leafQueueTemplate;
+  }
+
+  protected void validate(final CSQueue newlyParsedQueue) throws IOException {
+    // Sanity check
+    if (!(newlyParsedQueue instanceof ManagedParentQueue) || !newlyParsedQueue
+        .getQueuePath().equals(getQueuePath())) {
+      throw new IOException(
+          "Trying to reinitialize " + getQueuePath() + " from "
+              + newlyParsedQueue.getQueuePath());
+    }
+  }
+
+  @Override
+  public void addChildQueue(CSQueue childQueue)
+      throws SchedulerDynamicEditException {
+    try {
+      writeLock.lock();
+
+      if (childQueue == null || !(childQueue instanceof AutoCreatedLeafQueue)) {
+        throw new SchedulerDynamicEditException(
+            "Expected child queue to be an instance of AutoCreatedLeafQueue");
+      }
+
+      CapacitySchedulerConfiguration conf = csContext.getConfiguration();
+      ManagedParentQueue parentQueue =
+          (ManagedParentQueue) childQueue.getParent();
+
+      String leafQueueName = childQueue.getQueueName();
+      int maxQueues = conf.getAutoCreatedQueuesMaxChildQueuesLimit(
+          parentQueue.getQueuePath());
+
+      if (parentQueue.getChildQueues().size() >= maxQueues) {
+        throw new SchedulerDynamicEditException(
+            "Cannot auto create leaf queue " + leafQueueName + ".Max Child "
+                + "Queue limit exceeded which is configured as : " + maxQueues
+                + " and number of child queues is : " + parentQueue
+                .getChildQueues().size());
+      }
+
+      if (shouldFailAutoCreationWhenGuaranteedCapacityExceeded) {
+        if (getLeafQueueTemplate().getQueueCapacities().getAbsoluteCapacity()
+            + parentQueue.sumOfChildAbsCapacities() > parentQueue
+            .getAbsoluteCapacity()) {
+          throw new SchedulerDynamicEditException(
+              "Cannot auto create leaf queue " + leafQueueName + ". Child "
+                  + "queues capacities have reached parent queue : "
+                  + parentQueue.getQueuePath() + " guaranteed capacity");
+        }
+      }
+
+      AutoCreatedLeafQueue leafQueue = (AutoCreatedLeafQueue) childQueue;
+      super.addChildQueue(leafQueue);
+      //TODO - refresh policy queue after capacity management is added
+
+    } finally {
+      writeLock.unlock();
+    }
+  }
+
+  private String getLeafQueueConfigPrefix(CapacitySchedulerConfiguration conf) {
+    return conf.getAutoCreatedQueueTemplateConfPrefix(getQueuePath());
+  }
+
+}

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/scheduler/capacity/ParentQueue.java

@@ -1081,17 +1081,4 @@ public void stopQueue() {
   public QueueOrderingPolicy getQueueOrderingPolicy() {
     return queueOrderingPolicy;
   }
-
-  protected float sumOfChildCapacities() {
-    try {
-      writeLock.lock();
-      float ret = 0;
-      for (CSQueue l : childQueues) {
-        ret += l.getCapacity();
-      }
-      return ret;
-    } finally {
-      writeLock.unlock();
-    }
-  }
 }

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/scheduler/capacity/PlanQueue.java

@@ -40,6 +40,19 @@ public class PlanQueue extends AbstractManagedParentQueue {
   public PlanQueue(CapacitySchedulerContext cs, String queueName,
       CSQueue parent, CSQueue old) throws IOException {
     super(cs, queueName, parent, old);
+    this.leafQueueTemplate = initializeLeafQueueConfigs(getQueuePath()).build();
+
+    StringBuffer queueInfo = new StringBuffer();
+    queueInfo.append("Created Plan Queue: ").append(queueName).append(
+        "]\nwith capacity: [").append(super.getCapacity()).append(
+        "]\nwith max capacity: [").append(super.getMaximumCapacity()).append(
+        "\nwith max apps: [").append(leafQueueTemplate.getMaxApps()).append(
+        "]\nwith max apps per user: [").append(
+        leafQueueTemplate.getMaxAppsPerUser()).append("]\nwith user limit: [")
+        .append(leafQueueTemplate.getUserLimit()).append(
+        "]\nwith user limit factor: [").append(
+        leafQueueTemplate.getUserLimitFactor()).append("].");
+    LOG.info(queueInfo.toString());
   }
 
   @Override
@@ -47,17 +60,21 @@ public void reinitialize(CSQueue newlyParsedQueue, Resource clusterResource)
       throws IOException {
     validate(newlyParsedQueue);
     super.reinitialize(newlyParsedQueue, clusterResource);
+    this.leafQueueTemplate = initializeLeafQueueConfigs(getQueuePath()).build();
   }
 
   @Override
-  protected void initializeLeafQueueConfigs() {
-    String queuePath = super.getQueuePath();
+  protected AutoCreatedLeafQueueTemplate.Builder initializeLeafQueueConfigs
+      (String queuePath) {
+    AutoCreatedLeafQueueTemplate.Builder leafQueueTemplate = super
+        .initializeLeafQueueConfigs
+        (queuePath);
     showReservationsAsQueues = csContext.getConfiguration()
         .getShowReservationAsQueues(queuePath);
-    super.initializeLeafQueueConfigs();
+    return leafQueueTemplate;
   }
 
-  private void validate(final CSQueue newlyParsedQueue) throws IOException {
+  protected void validate(final CSQueue newlyParsedQueue) throws IOException {
     // Sanity check
     if (!(newlyParsedQueue instanceof PlanQueue) || !newlyParsedQueue
         .getQueuePath().equals(getQueuePath())) {

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/scheduler/event/AppAddedSchedulerEvent.java

@@ -6,9 +6,9 @@
  * 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
- *
+ * <p>
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * <p>
  * 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.
@@ -22,6 +22,8 @@
 import org.apache.hadoop.yarn.api.records.ApplicationSubmissionContext;
 import org.apache.hadoop.yarn.api.records.Priority;
 import org.apache.hadoop.yarn.api.records.ReservationId;
+import org.apache.hadoop.yarn.server.resourcemanager.placement
+    .ApplicationPlacementContext;
 
 public class AppAddedSchedulerEvent extends SchedulerEvent {
 
@@ -31,15 +33,23 @@ public class AppAddedSchedulerEvent extends SchedulerEvent {
   private final ReservationId reservationID;
   private final boolean isAppRecovering;
   private final Priority appPriority;
+  private final ApplicationPlacementContext placementContext;
 
   public AppAddedSchedulerEvent(ApplicationId applicationId, String queue,
       String user) {
-    this(applicationId, queue, user, false, null, Priority.newInstance(0));
+    this(applicationId, queue, user, false, null, Priority.newInstance(0),
+        null);
+  }
+
+  public AppAddedSchedulerEvent(ApplicationId applicationId, String queue,
+      String user, ApplicationPlacementContext placementContext) {
+    this(applicationId, queue, user, false, null, Priority.newInstance(0),
+        placementContext);
   }
 
   public AppAddedSchedulerEvent(ApplicationId applicationId, String queue,
       String user, ReservationId reservationID, Priority appPriority) {
-    this(applicationId, queue, user, false, reservationID, appPriority);
+    this(applicationId, queue, user, false, reservationID, appPriority, null);
   }
 
   public AppAddedSchedulerEvent(String user,
@@ -47,12 +57,20 @@ public AppAddedSchedulerEvent(String user,
       Priority appPriority) {
     this(submissionContext.getApplicationId(), submissionContext.getQueue(),
         user, isAppRecovering, submissionContext.getReservationID(),
-        appPriority);
+        appPriority, null);
+  }
+
+  public AppAddedSchedulerEvent(String user,
+      ApplicationSubmissionContext submissionContext, boolean isAppRecovering,
+      Priority appPriority, ApplicationPlacementContext placementContext) {
+    this(submissionContext.getApplicationId(), submissionContext.getQueue(),
+        user, isAppRecovering, submissionContext.getReservationID(),
+        appPriority, placementContext);
   }
 
   public AppAddedSchedulerEvent(ApplicationId applicationId, String queue,
       String user, boolean isAppRecovering, ReservationId reservationID,
-      Priority appPriority) {
+      Priority appPriority, ApplicationPlacementContext placementContext) {
     super(SchedulerEventType.APP_ADDED);
     this.applicationId = applicationId;
     this.queue = queue;
@@ -60,6 +78,7 @@ public AppAddedSchedulerEvent(ApplicationId applicationId, String queue,
     this.reservationID = reservationID;
     this.isAppRecovering = isAppRecovering;
     this.appPriority = appPriority;
+    this.placementContext = placementContext;
   }
 
   public ApplicationId getApplicationId() {
@@ -85,4 +104,8 @@ public ReservationId getReservationID() {
   public Priority getApplicatonPriority() {
     return appPriority;
   }
+
+  public ApplicationPlacementContext getPlacementContext() {
+    return placementContext;
+  }
 }

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

@@ -44,7 +44,6 @@
 import org.apache.hadoop.fs.CommonConfigurationKeysPublic;
 import org.apache.hadoop.io.DataOutputBuffer;
 import org.apache.hadoop.security.AccessControlException;
-import org.apache.hadoop.security.Credentials;
 import org.apache.hadoop.security.UserGroupInformation;
 import org.apache.hadoop.service.Service;
 import org.apache.hadoop.yarn.MockApps;
@@ -70,6 +69,7 @@
 import org.apache.hadoop.yarn.server.resourcemanager.ahs.RMApplicationHistoryWriter;
 import org.apache.hadoop.yarn.server.resourcemanager.metrics.SystemMetricsPublisher;
 import org.apache.hadoop.yarn.server.resourcemanager.nodelabels.RMNodeLabelsManager;
+import org.apache.hadoop.yarn.server.resourcemanager.placement.ApplicationPlacementContext;
 import org.apache.hadoop.yarn.server.resourcemanager.placement.PlacementManager;
 import org.apache.hadoop.yarn.server.resourcemanager.recovery.RMStateStore;
 import org.apache.hadoop.yarn.server.resourcemanager.rmapp.MockRMApp;
@@ -84,7 +84,6 @@
 import org.apache.hadoop.yarn.server.resourcemanager.rmcontainer.ContainerAllocationExpirer;
 import org.apache.hadoop.yarn.server.resourcemanager.scheduler.ResourceScheduler;
 import org.apache.hadoop.yarn.server.resourcemanager.scheduler.YarnScheduler;
-import org.apache.hadoop.yarn.server.resourcemanager.scheduler.capacity.CapacityScheduler;
 import org.apache.hadoop.yarn.server.resourcemanager.security.ClientToAMTokenSecretManagerInRM;
 import org.apache.hadoop.yarn.server.resourcemanager.timelineservice.RMTimelineCollectorManager;
 import org.apache.hadoop.yarn.server.security.ApplicationACLsManager;
@@ -856,28 +855,32 @@ public void testEscapeApplicationSummary() {
     Assert.assertTrue(msg.contains("preemptedResources=<memory:1234\\, vCores:56>"));
     Assert.assertTrue(msg.contains("applicationType=MAPREDUCE"));
  }
-  
+
   @Test
   public void testRMAppSubmitWithQueueChanged() throws Exception {
     // Setup a PlacementManager returns a new queue
     PlacementManager placementMgr = mock(PlacementManager.class);
-    doAnswer(new Answer<Void>() {
+    doAnswer(new Answer<ApplicationPlacementContext>() {
 
       @Override
-      public Void answer(InvocationOnMock invocation) throws Throwable {
-        ApplicationSubmissionContext ctx =
-            (ApplicationSubmissionContext) invocation.getArguments()[0];
-        ctx.setQueue("newQueue");
-        return null;
+      public ApplicationPlacementContext answer(InvocationOnMock invocation)
+          throws Throwable {
+        return new ApplicationPlacementContext("newQueue");
       }
-      
-    }).when(placementMgr).placeApplication(any(ApplicationSubmissionContext.class),
-            any(String.class));
+
+    }).when(placementMgr).placeApplication(
+        any(ApplicationSubmissionContext.class), any(String.class));
     rmContext.setQueuePlacementManager(placementMgr);
-    
+
     asContext.setQueue("oldQueue");
     appMonitor.submitApplication(asContext, "test");
+
     RMApp app = rmContext.getRMApps().get(appId);
+    RMAppEvent event = new RMAppEvent(appId, RMAppEventType.START);
+    rmContext.getRMApps().get(appId).handle(event);
+    event = new RMAppEvent(appId, RMAppEventType.APP_NEW_SAVED);
+    rmContext.getRMApps().get(appId).handle(event);
+
     Assert.assertNotNull("app is null", app);
     Assert.assertEquals("newQueue", asContext.getQueue());
 

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

@@ -52,14 +52,14 @@ private void verifyQueueMapping(QueueMapping queueMapping, String inputUser,
   private void verifyQueueMapping(QueueMapping queueMapping, String inputUser,
       String inputQueue, String expectedQueue, boolean overwrite) throws YarnException {
     Groups groups = new Groups(conf);
-    UserGroupMappingPlacementRule rule =
-        new UserGroupMappingPlacementRule(overwrite, Arrays.asList(queueMapping),
-            groups);
-    ApplicationSubmissionContext asc =
-        Records.newRecord(ApplicationSubmissionContext.class);
+    UserGroupMappingPlacementRule rule = new UserGroupMappingPlacementRule(
+        overwrite, Arrays.asList(queueMapping), groups);
+    ApplicationSubmissionContext asc = Records.newRecord(
+        ApplicationSubmissionContext.class);
     asc.setQueue(inputQueue);
-    String queue = rule.getQueueForApp(asc, inputUser);
-    Assert.assertEquals(expectedQueue, queue);
+    ApplicationPlacementContext ctx = rule.getPlacementForApp(asc, inputUser);
+    Assert.assertEquals(expectedQueue,
+        ctx != null ? ctx.getQueue() : inputQueue);
   }
 
   @Test

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

@@ -803,6 +803,7 @@ public static void waitSchedulerApplicationAttemptStopped(
           Map<ApplicationId, SchedulerApplication<SchedulerApplicationAttempt>> applications,
           EventHandler<SchedulerEvent> handler, String queueName)
           throws Exception {
+
     ApplicationId appId =
         ApplicationId.newInstance(System.currentTimeMillis(), 1);
     AppAddedSchedulerEvent appAddedEvent =

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

@@ -103,6 +103,7 @@
 import org.apache.hadoop.yarn.server.resourcemanager.TestAMAuthorization.MyContainerManager;
 import org.apache.hadoop.yarn.server.resourcemanager.nodelabels.NullRMNodeLabelsManager;
 import org.apache.hadoop.yarn.server.resourcemanager.nodelabels.RMNodeLabelsManager;
+import org.apache.hadoop.yarn.server.resourcemanager.placement.UserGroupMappingPlacementRule;
 import org.apache.hadoop.yarn.server.resourcemanager.rmapp.RMApp;
 import org.apache.hadoop.yarn.server.resourcemanager.rmapp.RMAppImpl;
 import org.apache.hadoop.yarn.server.resourcemanager.rmapp.RMAppMetrics;
@@ -904,7 +905,7 @@ void checkQueueCapacities(CapacityScheduler cs,
         (B3_CAPACITY/100.0f) * capB, 1.0f, 1.0f);
   }
 
-  private void checkQueueCapacity(CSQueue q, float expectedCapacity,
+  void checkQueueCapacity(CSQueue q, float expectedCapacity,
       float expectedAbsCapacity, float expectedMaxCapacity,
       float expectedAbsMaxCapacity) {
     final float epsilon = 1e-5f;
@@ -917,7 +918,7 @@ private void checkQueueCapacity(CSQueue q, float expectedCapacity,
         q.getAbsoluteMaximumCapacity(), epsilon);
   }
 
-  private CSQueue findQueue(CSQueue root, String queuePath) {
+  CSQueue findQueue(CSQueue root, String queuePath) {
     if (root.getQueuePath().equals(queuePath)) {
       return root;
     }
@@ -1396,7 +1397,6 @@ public void testAddAndRemoveAppFromCapacityScheduler() throws Exception {
     AbstractYarnScheduler<SchedulerApplicationAttempt, SchedulerNode> cs =
         (AbstractYarnScheduler<SchedulerApplicationAttempt, SchedulerNode>) rm
           .getResourceScheduler();
-
     SchedulerApplication<SchedulerApplicationAttempt> app =
         TestSchedulerUtils.verifyAppAddedAndRemovedFromScheduler(
           cs.getSchedulerApplications(), cs, "a1");

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

@@ -0,0 +1,794 @@
+/**
+ * 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
+ * <p>
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * <p>
+ * 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.scheduler.capacity;
+
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
+import org.apache.hadoop.yarn.api.records.ApplicationAttemptId;
+import org.apache.hadoop.yarn.api.records.ApplicationId;
+import org.apache.hadoop.yarn.api.records.ContainerId;
+import org.apache.hadoop.yarn.api.records.Priority;
+import org.apache.hadoop.yarn.api.records.QueueState;
+import org.apache.hadoop.yarn.api.records.ResourceRequest;
+import org.apache.hadoop.yarn.conf.YarnConfiguration;
+import org.apache.hadoop.yarn.event.AsyncDispatcher;
+import org.apache.hadoop.yarn.event.Event;
+import org.apache.hadoop.yarn.event.EventHandler;
+import org.apache.hadoop.yarn.exceptions.YarnException;
+import org.apache.hadoop.yarn.factories.RecordFactory;
+import org.apache.hadoop.yarn.factory.providers.RecordFactoryProvider;
+import org.apache.hadoop.yarn.server.resourcemanager.MockNodes;
+import org.apache.hadoop.yarn.server.resourcemanager.MockRM;
+import org.apache.hadoop.yarn.server.resourcemanager.RMContext;
+import org.apache.hadoop.yarn.server.resourcemanager.RMContextImpl;
+import org.apache.hadoop.yarn.server.resourcemanager.placement.ApplicationPlacementContext;
+import org.apache.hadoop.yarn.server.resourcemanager.placement.UserGroupMappingPlacementRule;
+import org.apache.hadoop.yarn.server.resourcemanager.rmapp.RMApp;
+import org.apache.hadoop.yarn.server.resourcemanager.rmapp.RMAppEvent;
+import org.apache.hadoop.yarn.server.resourcemanager.rmapp.RMAppEventType;
+import org.apache.hadoop.yarn.server.resourcemanager.rmapp.RMAppState;
+import org.apache.hadoop.yarn.server.resourcemanager.rmapp.attempt.RMAppAttemptState;
+import org.apache.hadoop.yarn.server.resourcemanager.rmnode.RMNode;
+import org.apache.hadoop.yarn.server.resourcemanager.scheduler.ContainerUpdates;
+import org.apache.hadoop.yarn.server.resourcemanager.scheduler.ResourceScheduler;
+import org.apache.hadoop.yarn.server.resourcemanager.scheduler.SchedulerDynamicEditException;
+import org.apache.hadoop.yarn.server.resourcemanager.scheduler.common.QueueEntitlement;
+import org.apache.hadoop.yarn.server.resourcemanager.scheduler.event.AppAddedSchedulerEvent;
+import org.apache.hadoop.yarn.server.resourcemanager.scheduler.event.AppAttemptAddedSchedulerEvent;
+import org.apache.hadoop.yarn.server.resourcemanager.scheduler.event.NodeAddedSchedulerEvent;
+import org.apache.hadoop.yarn.server.resourcemanager.scheduler.event.SchedulerEvent;
+import org.apache.hadoop.yarn.server.resourcemanager.security.ClientToAMTokenSecretManagerInRM;
+import org.apache.hadoop.yarn.server.resourcemanager.security.NMTokenSecretManagerInRM;
+import org.apache.hadoop.yarn.server.resourcemanager.security.RMContainerTokenSecretManager;
+import org.apache.hadoop.yarn.server.utils.BuilderUtils;
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+import java.util.concurrent.BlockingQueue;
+import java.util.concurrent.LinkedBlockingQueue;
+import java.util.concurrent.TimeUnit;
+
+import static org.apache.hadoop.yarn.server.resourcemanager.placement.UserGroupMappingPlacementRule.CURRENT_USER_MAPPING;
+import static org.apache.hadoop.yarn.server.resourcemanager.scheduler.capacity.CSQueueUtils.EPSILON;
+import static org.apache.hadoop.yarn.server.resourcemanager.scheduler.capacity.CapacitySchedulerConfiguration.DOT;
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.assertTrue;
+import static org.junit.Assert.fail;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.when;
+
+/**
+ * Tests for creation and reinitilization of auto created leaf queues
+ * under a ManagedParentQueue.
+ */
+public class TestCapacitySchedulerAutoQueueCreation {
+
+  private static final Log LOG = LogFactory.getLog(TestCapacityScheduler.class);
+  private final int GB = 1024;
+  private final static ContainerUpdates NULL_UPDATE_REQUESTS =
+      new ContainerUpdates();
+
+  private static final String A = CapacitySchedulerConfiguration.ROOT + ".a";
+  private static final String B = CapacitySchedulerConfiguration.ROOT + ".b";
+  private static final String C = CapacitySchedulerConfiguration.ROOT + ".c";
+  private static final String D = CapacitySchedulerConfiguration.ROOT + ".d";
+  private static final String A1 = A + ".a1";
+  private static final String A2 = A + ".a2";
+  private static final String B1 = B + ".b1";
+  private static final String B2 = B + ".b2";
+  private static final String B3 = B + ".b3";
+  private static final String C1 = C + ".c1";
+  private static final String C2 = C + ".c2";
+  private static final String C3 = C + ".c3";
+  private static float A_CAPACITY = 20f;
+  private static float B_CAPACITY = 40f;
+  private static float C_CAPACITY = 20f;
+  private static float D_CAPACITY = 20f;
+  private static float A1_CAPACITY = 30;
+  private static float A2_CAPACITY = 70;
+  private static float B1_CAPACITY = 60f;
+  private static float B2_CAPACITY = 20f;
+  private static float B3_CAPACITY = 20f;
+  private static float C1_CAPACITY = 20f;
+  private static float C2_CAPACITY = 20f;
+
+  private static String USER = "user_";
+  private static String USER0 = USER + 0;
+  private static String USER2 = USER + 2;
+  private static String PARENT_QUEUE = "c";
+
+  private MockRM mockRM = null;
+
+  private CapacityScheduler cs;
+
+  private final TestCapacityScheduler tcs = new TestCapacityScheduler();
+
+  private static SpyDispatcher dispatcher;
+
+  private static EventHandler<Event> rmAppEventEventHandler;
+
+  private static class SpyDispatcher extends AsyncDispatcher {
+
+    private static BlockingQueue<Event> eventQueue =
+        new LinkedBlockingQueue<>();
+
+    private static class SpyRMAppEventHandler implements EventHandler<Event> {
+      public void handle(Event event) {
+        eventQueue.add(event);
+      }
+    }
+
+    @Override
+    protected void dispatch(Event event) {
+      eventQueue.add(event);
+    }
+
+    @Override
+    public EventHandler<Event> getEventHandler() {
+      return rmAppEventEventHandler;
+    }
+
+    void spyOnNextEvent(Event expectedEvent, long timeout)
+        throws InterruptedException {
+
+      Event event = eventQueue.poll(timeout, TimeUnit.MILLISECONDS);
+      assertEquals(expectedEvent.getType(), event.getType());
+      assertEquals(expectedEvent.getClass(), event.getClass());
+    }
+  }
+
+  @Before
+  public void setUp() throws Exception {
+    CapacitySchedulerConfiguration conf = new CapacitySchedulerConfiguration();
+    setupQueueConfiguration(conf);
+    conf.setClass(YarnConfiguration.RM_SCHEDULER, CapacityScheduler.class,
+        ResourceScheduler.class);
+
+    List<String> queuePlacementRules = new ArrayList<>();
+    queuePlacementRules.add(YarnConfiguration.USER_GROUP_PLACEMENT_RULE);
+    conf.setQueuePlacementRules(queuePlacementRules);
+
+    setupQueueMappings(conf);
+
+    mockRM = new MockRM(conf);
+    cs = (CapacityScheduler) mockRM.getResourceScheduler();
+
+    dispatcher = new SpyDispatcher();
+    rmAppEventEventHandler = new SpyDispatcher.SpyRMAppEventHandler();
+    dispatcher.register(RMAppEventType.class, rmAppEventEventHandler);
+    cs.updatePlacementRules();
+    mockRM.start();
+
+    cs.start();
+  }
+
+  private CapacitySchedulerConfiguration setupQueueMappings(
+      CapacitySchedulerConfiguration conf) {
+
+    //set queue mapping
+    List<UserGroupMappingPlacementRule.QueueMapping> queueMappings =
+        new ArrayList<>();
+    for (int i = 0; i <= 3; i++) {
+      //Set C as parent queue name for auto queue creation
+      UserGroupMappingPlacementRule.QueueMapping userQueueMapping =
+          new UserGroupMappingPlacementRule.QueueMapping(
+              UserGroupMappingPlacementRule.QueueMapping.MappingType.USER,
+              USER + i, getQueueMapping(PARENT_QUEUE, USER + i));
+      queueMappings.add(userQueueMapping);
+    }
+
+    conf.setQueueMappings(queueMappings);
+    //override with queue mappings
+    conf.setOverrideWithQueueMappings(true);
+    return conf;
+  }
+
+  /**
+   * @param conf, to be modified
+   * @return, CS configuration which has C
+   * as an auto creation enabled parent queue
+   * <p>
+   * root
+   * /     \      \       \
+   * a        b      c    d
+   * / \    /  |  \
+   * a1  a2 b1  b2  b3
+   */
+  private CapacitySchedulerConfiguration setupQueueConfiguration(
+      CapacitySchedulerConfiguration conf) {
+
+    //setup new queues with one of them auto enabled
+    // Define top-level queues
+    // Set childQueue for root
+    conf.setQueues(CapacitySchedulerConfiguration.ROOT,
+        new String[] { "a", "b", "c", "d" });
+
+    conf.setCapacity(A, A_CAPACITY);
+    conf.setCapacity(B, B_CAPACITY);
+    conf.setCapacity(C, C_CAPACITY);
+    conf.setCapacity(D, D_CAPACITY);
+
+    // Define 2nd-level queues
+    conf.setQueues(A, new String[] { "a1", "a2" });
+    conf.setCapacity(A1, A1_CAPACITY);
+    conf.setUserLimitFactor(A1, 100.0f);
+    conf.setCapacity(A2, A2_CAPACITY);
+    conf.setUserLimitFactor(A2, 100.0f);
+
+    conf.setQueues(B, new String[] { "b1", "b2", "b3" });
+    conf.setCapacity(B1, B1_CAPACITY);
+    conf.setUserLimitFactor(B1, 100.0f);
+    conf.setCapacity(B2, B2_CAPACITY);
+    conf.setUserLimitFactor(B2, 100.0f);
+    conf.setCapacity(B3, B3_CAPACITY);
+    conf.setUserLimitFactor(B3, 100.0f);
+
+    conf.setUserLimitFactor(C, 1.0f);
+    conf.setAutoCreateChildQueueEnabled(C, true);
+
+    //Setup leaf queue template configs
+    conf.setAutoCreatedLeafQueueTemplateCapacity(C, 50.0f);
+    conf.setAutoCreatedLeafQueueTemplateMaxCapacity(C, 100.0f);
+
+    LOG.info("Setup " + C + " as an auto leaf creation enabled parent queue");
+
+    conf.setUserLimitFactor(D, 1.0f);
+    conf.setAutoCreateChildQueueEnabled(D, true);
+
+    //Setup leaf queue template configs
+    conf.setAutoCreatedLeafQueueTemplateCapacity(D, 10.0f);
+    conf.setAutoCreatedLeafQueueTemplateMaxCapacity(D, 100.0f);
+
+    LOG.info("Setup " + D + " as an auto leaf creation enabled parent queue");
+
+    return conf;
+  }
+
+  @After
+  public void tearDown() throws Exception {
+    if (mockRM != null) {
+      mockRM.stop();
+    }
+  }
+
+  @Test(timeout = 10000)
+  public void testAutoCreateLeafQueueCreation() throws Exception {
+
+    try {
+      // submit an app
+      submitApp(cs, USER0, USER0, PARENT_QUEUE);
+
+      // check preconditions
+      List<ApplicationAttemptId> appsInC = cs.getAppsInQueue(PARENT_QUEUE);
+      assertEquals(1, appsInC.size());
+      assertNotNull(cs.getQueue(USER0));
+
+      AutoCreatedLeafQueue autoCreatedLeafQueue =
+          (AutoCreatedLeafQueue) cs.getQueue(USER0);
+      ManagedParentQueue parentQueue = (ManagedParentQueue) cs.getQueue(
+          PARENT_QUEUE);
+      assertEquals(parentQueue, autoCreatedLeafQueue.getParent());
+      validateCapacities(autoCreatedLeafQueue);
+    } finally {
+      cleanupQueue(USER0);
+    }
+  }
+
+  @Test
+  public void testReinitializeStoppedAutoCreatedLeafQueue() throws Exception {
+
+    try {
+      String host = "127.0.0.1";
+      RMNode node = MockNodes.newNodeInfo(0, MockNodes.newResource(4 * GB), 1,
+          host);
+      cs.handle(new NodeAddedSchedulerEvent(node));
+
+      // submit an app
+
+      RMApp app = mockRM.submitApp(GB, "test-auto-queue-creation-1", USER0,
+          null, USER0);
+      // check preconditions
+      List<ApplicationAttemptId> appsInC = cs.getAppsInQueue(PARENT_QUEUE);
+      assertEquals(1, appsInC.size());
+
+      assertNotNull(cs.getQueue(USER0));
+
+      AutoCreatedLeafQueue autoCreatedLeafQueue =
+          (AutoCreatedLeafQueue) cs.getQueue(USER0);
+      ManagedParentQueue parentQueue = (ManagedParentQueue) cs.getQueue(
+          PARENT_QUEUE);
+      assertEquals(parentQueue, autoCreatedLeafQueue.getParent());
+      validateCapacities(autoCreatedLeafQueue);
+
+      ApplicationAttemptId appAttemptId = appsInC.get(0);
+
+      Priority priority = TestUtils.createMockPriority(1);
+      RecordFactory recordFactory = RecordFactoryProvider.getRecordFactory(
+          null);
+      ResourceRequest r1 = TestUtils.createResourceRequest(ResourceRequest.ANY,
+          1 * GB, 1, true, priority, recordFactory);
+
+      cs.allocate(appAttemptId, Collections.<ResourceRequest>singletonList(r1),
+          Collections.<ContainerId>emptyList(), Collections.singletonList(host),
+          null, NULL_UPDATE_REQUESTS);
+
+      //And this will result in container assignment for app1
+      CapacityScheduler.schedule(cs);
+
+      //change state to draining
+      autoCreatedLeafQueue.stopQueue();
+
+      cs.killAllAppsInQueue(USER0);
+
+      mockRM.waitForState(appAttemptId, RMAppAttemptState.KILLED);
+
+      mockRM.waitForState(appAttemptId.getApplicationId(), RMAppState.KILLED);
+
+      //change state to stopped
+      autoCreatedLeafQueue.stopQueue();
+      assertEquals(QueueState.STOPPED,
+          autoCreatedLeafQueue.getQueueInfo().getQueueState());
+
+      cs.reinitialize(cs.getConf(), mockRM.getRMContext());
+
+      AutoCreatedLeafQueue leafQueue = (AutoCreatedLeafQueue) cs.getQueue(
+          USER0);
+      validateCapacities(leafQueue);
+
+    } finally {
+      cleanupQueue(USER0);
+    }
+  }
+
+  @Test
+  public void testRefreshQueuesWithAutoCreatedLeafQueues() throws Exception {
+
+    MockRM newMockRM = setupSchedulerInstance();
+    try {
+      CapacityScheduler newCS =
+          (CapacityScheduler) newMockRM.getResourceScheduler();
+      CapacitySchedulerConfiguration conf = newCS.getConfiguration();
+
+      // Test add one auto created queue dynamically and manually modify
+      // capacity
+      ManagedParentQueue parentQueue = (ManagedParentQueue) newCS.getQueue("c");
+      AutoCreatedLeafQueue c1 = new AutoCreatedLeafQueue(newCS, "c1",
+          parentQueue);
+      newCS.addQueue(c1);
+      c1.setEntitlement(new QueueEntitlement(C1_CAPACITY / 100, 1f));
+
+      // Test add another auto created queue and use setEntitlement to modify
+      // capacity
+      AutoCreatedLeafQueue c2 = new AutoCreatedLeafQueue(newCS, "c2",
+          (ManagedParentQueue) newCS.getQueue("c"));
+      newCS.addQueue(c2);
+      newCS.setEntitlement("c2", new QueueEntitlement(C2_CAPACITY / 100, 1f));
+
+      // Verify all allocations match
+      checkQueueCapacities(newCS, C_CAPACITY, D_CAPACITY);
+
+      // Reinitialize and verify all dynamic queued survived
+
+      conf.setCapacity(A, 20f);
+      conf.setCapacity(B, 20f);
+      conf.setCapacity(C, 40f);
+      conf.setCapacity(D, 20f);
+      newCS.reinitialize(conf, newMockRM.getRMContext());
+
+      checkQueueCapacities(newCS, 40f, 20f);
+
+      //chnage parent template configs and reinitialize
+      conf.setAutoCreatedLeafQueueTemplateCapacity(C, 30.0f);
+      conf.setAutoCreatedLeafQueueTemplateMaxCapacity(C, 100.0f);
+      newCS.reinitialize(conf, newMockRM.getRMContext());
+
+      ManagedParentQueue c = (ManagedParentQueue) newCS.getQueue("c");
+      AutoCreatedLeafQueue c3 = new AutoCreatedLeafQueue(newCS, "c3", c);
+      newCS.addQueue(c3);
+
+      AbstractManagedParentQueue.AutoCreatedLeafQueueTemplate
+          leafQueueTemplate = parentQueue.getLeafQueueTemplate();
+      QueueCapacities cap = leafQueueTemplate.getQueueCapacities();
+      c3.setEntitlement(
+          new QueueEntitlement(cap.getCapacity(), cap.getMaximumCapacity()));
+      newCS.reinitialize(conf, newMockRM.getRMContext());
+
+      checkQueueCapacities(newCS, 40f, 20f);
+    } finally {
+      if (newMockRM != null) {
+        ((CapacityScheduler) newMockRM.getResourceScheduler()).stop();
+        newMockRM.stop();
+      }
+    }
+  }
+
+  @Test
+  public void testConvertAutoCreateDisabledOnManagedParentQueueFails()
+      throws Exception {
+    CapacityScheduler newCS = new CapacityScheduler();
+    try {
+      CapacitySchedulerConfiguration newConf =
+          new CapacitySchedulerConfiguration();
+      setupQueueConfiguration(newConf);
+
+      newConf.setAutoCreateChildQueueEnabled(C, false);
+
+      newCS.setConf(new YarnConfiguration());
+      newCS.setRMContext(mockRM.getRMContext());
+      newCS.init(cs.getConf());
+      newCS.start();
+
+      newCS.reinitialize(newConf,
+          new RMContextImpl(null, null, null, null, null, null,
+              new RMContainerTokenSecretManager(newConf),
+              new NMTokenSecretManagerInRM(newConf),
+              new ClientToAMTokenSecretManagerInRM(), null));
+
+    } catch (IOException e) {
+      //expected exception
+    } finally {
+      newCS.stop();
+    }
+  }
+
+  @Test
+  public void testConvertLeafQueueToParentQueueWithAutoCreate()
+      throws Exception {
+    CapacityScheduler newCS = new CapacityScheduler();
+    try {
+      CapacitySchedulerConfiguration newConf =
+          new CapacitySchedulerConfiguration();
+      setupQueueConfiguration(newConf);
+      newConf.setAutoCreatedLeafQueueTemplateCapacity(A1, A1_CAPACITY / 10);
+      newConf.setAutoCreateChildQueueEnabled(A1, true);
+
+      newCS.setConf(new YarnConfiguration());
+      newCS.setRMContext(mockRM.getRMContext());
+      newCS.init(cs.getConf());
+      newCS.start();
+
+      final LeafQueue a1Queue = (LeafQueue) newCS.getQueue("a1");
+      a1Queue.stopQueue();
+
+      newCS.reinitialize(newConf,
+          new RMContextImpl(null, null, null, null, null, null,
+              new RMContainerTokenSecretManager(newConf),
+              new NMTokenSecretManagerInRM(newConf),
+              new ClientToAMTokenSecretManagerInRM(), null));
+
+    } finally {
+      newCS.stop();
+    }
+  }
+
+  @Test
+  public void testConvertFailsFromParentQueueToManagedParentQueue()
+      throws Exception {
+    CapacityScheduler newCS = new CapacityScheduler();
+    try {
+      CapacitySchedulerConfiguration newConf =
+          new CapacitySchedulerConfiguration();
+      setupQueueConfiguration(newConf);
+      newConf.setAutoCreatedLeafQueueTemplateCapacity(A, A_CAPACITY / 10);
+      newConf.setAutoCreateChildQueueEnabled(A, true);
+
+      newCS.setConf(new YarnConfiguration());
+      newCS.setRMContext(mockRM.getRMContext());
+      newCS.init(cs.getConf());
+      newCS.start();
+
+      final ParentQueue a1Queue = (ParentQueue) newCS.getQueue("a");
+      a1Queue.stopQueue();
+
+      newCS.reinitialize(newConf,
+          new RMContextImpl(null, null, null, null, null, null,
+              new RMContainerTokenSecretManager(newConf),
+              new NMTokenSecretManagerInRM(newConf),
+              new ClientToAMTokenSecretManagerInRM(), null));
+
+      fail("Expected exception while converting a parent queue to"
+          + " an auto create enabled parent queue");
+    } catch (IOException e) {
+      //expected exception
+    } finally {
+      newCS.stop();
+    }
+  }
+
+  @Test(timeout = 10000)
+  public void testAutoCreateLeafQueueFailsWithNoQueueMapping()
+      throws Exception {
+
+    final String INVALID_USER = "invalid_user";
+
+    // submit an app under a different queue name which does not exist
+    // and queue mapping does not exist for this user
+    RMApp app = mockRM.submitApp(GB, "app", INVALID_USER, null, INVALID_USER,
+        false);
+    mockRM.drainEvents();
+    mockRM.waitForState(app.getApplicationId(), RMAppState.FAILED);
+    assertEquals(RMAppState.FAILED, app.getState());
+  }
+
+  private void validateCapacities(AutoCreatedLeafQueue autoCreatedLeafQueue) {
+    assertEquals(autoCreatedLeafQueue.getCapacity(), 0.0f, EPSILON);
+    assertEquals(autoCreatedLeafQueue.getAbsoluteCapacity(), 0.0f, EPSILON);
+    assertEquals(autoCreatedLeafQueue.getMaximumCapacity(), 0.0f, EPSILON);
+    assertEquals(autoCreatedLeafQueue.getAbsoluteMaximumCapacity(), 0.0f,
+        EPSILON);
+    int maxAppsForAutoCreatedQueues = (int) (
+        CapacitySchedulerConfiguration.DEFAULT_MAXIMUM_SYSTEM_APPLICATIIONS
+            * autoCreatedLeafQueue.getParent().getAbsoluteCapacity());
+    assertEquals(autoCreatedLeafQueue.getMaxApplicationsPerUser(),
+        maxAppsForAutoCreatedQueues);
+    assertEquals(autoCreatedLeafQueue.getMaxApplicationsPerUser(),
+        (int) (maxAppsForAutoCreatedQueues * (cs.getConfiguration()
+            .getUserLimitFactor(
+                autoCreatedLeafQueue.getParent().getQueuePath()))));
+  }
+
+  private void cleanupQueue(String queueName) throws YarnException {
+    AutoCreatedLeafQueue queue = (AutoCreatedLeafQueue) cs.getQueue(queueName);
+    if (queue != null) {
+      queue.setEntitlement(new QueueEntitlement(0.0f, 0.0f));
+      ((ManagedParentQueue) queue.getParent()).removeChildQueue(
+          queue.getQueueName());
+      cs.getCapacitySchedulerQueueManager().removeQueue(queue.getQueueName());
+    } else{
+      throw new YarnException("Queue does not exist " + queueName);
+    }
+  }
+
+  String getQueueMapping(String parentQueue, String leafQueue) {
+    return parentQueue + DOT + leafQueue;
+  }
+
+  @Test(timeout = 10000)
+  public void testQueueMappingValidationFailsWithInvalidParentQueueInMapping()
+      throws Exception {
+
+    MockRM newMockRM = setupSchedulerInstance();
+    try {
+      CapacityScheduler newCS =
+          (CapacityScheduler) newMockRM.getResourceScheduler();
+
+      //"a" is not auto create enabled
+
+      //dynamic queue mapping
+      try {
+        setupQueueMapping(newCS, CURRENT_USER_MAPPING, "a",
+            CURRENT_USER_MAPPING);
+        newCS.updatePlacementRules();
+        fail("Expected invalid parent queue mapping failure");
+
+      } catch (IOException e) {
+        //expected exception
+        assertTrue(e.getMessage().contains(
+            "invalid parent queue which does not have auto creation of leaf "
+                + "queues enabled ["
+                + "a" + "]"));
+      }
+
+      //"a" is not auto create enabled and app_user does not exist as a leaf
+      // queue
+      //static queue mapping
+      try {
+        setupQueueMapping(newCS, "app_user", "INVALID_PARENT_QUEUE",
+            "app_user");
+        newCS.updatePlacementRules();
+        fail("Expected invalid parent queue mapping failure");
+      } catch (IOException e) {
+        //expected exception
+        assertTrue(e.getMessage()
+            .contains("invalid parent queue [" + "INVALID_PARENT_QUEUE" + "]"));
+      }
+    } finally {
+      if (newMockRM != null) {
+        ((CapacityScheduler) newMockRM.getResourceScheduler()).stop();
+        newMockRM.stop();
+      }
+    }
+  }
+
+  @Test(timeout = 10000)
+  public void testQueueMappingUpdatesFailsOnRemovalOfParentQueueInMapping()
+      throws Exception {
+
+    MockRM newMockRM = setupSchedulerInstance();
+
+    try {
+      CapacityScheduler newCS =
+          (CapacityScheduler) newMockRM.getResourceScheduler();
+
+      setupQueueMapping(newCS, CURRENT_USER_MAPPING, "c", CURRENT_USER_MAPPING);
+      newCS.updatePlacementRules();
+
+      try {
+        setupQueueMapping(newCS, CURRENT_USER_MAPPING, "",
+            CURRENT_USER_MAPPING);
+        newCS.updatePlacementRules();
+        fail("Expected invalid parent queue mapping failure");
+      } catch (IOException e) {
+        //expected exception
+        assertTrue(e.getMessage().contains("invalid parent queue []"));
+      }
+    } finally {
+      if (newMockRM != null) {
+        ((CapacityScheduler) newMockRM.getResourceScheduler()).stop();
+        newMockRM.stop();
+      }
+    }
+  }
+
+  @Test
+  public void testParentQueueUpdateInQueueMappingFailsAfterAutoCreation()
+      throws Exception {
+
+    MockRM newMockRM = setupSchedulerInstance();
+    CapacityScheduler newCS =
+        (CapacityScheduler) newMockRM.getResourceScheduler();
+
+    try {
+      newMockRM.start();
+      newCS.start();
+
+      submitApp(newCS, USER0, USER0, PARENT_QUEUE);
+
+      assertNotNull(newCS.getQueue(USER0));
+
+      setupQueueMapping(newCS, USER0, "d", USER0);
+      newCS.updatePlacementRules();
+
+      RMContext rmContext = mock(RMContext.class);
+      when(rmContext.getDispatcher()).thenReturn(dispatcher);
+      newCS.setRMContext(rmContext);
+
+      ApplicationId appId = BuilderUtils.newApplicationId(1, 1);
+      SchedulerEvent addAppEvent = new AppAddedSchedulerEvent(appId, USER0,
+          USER0, new ApplicationPlacementContext(USER0, "d"));
+      newCS.handle(addAppEvent);
+
+      RMAppEvent event = new RMAppEvent(appId, RMAppEventType.APP_REJECTED,
+          "error");
+      dispatcher.spyOnNextEvent(event, 10000);
+    } finally {
+      if (newMockRM != null) {
+        ((CapacityScheduler) newMockRM.getResourceScheduler()).stop();
+        newMockRM.stop();
+      }
+    }
+  }
+
+  @Test
+  public void testAutoCreationFailsWhenParentCapacityExceeded()
+      throws IOException, SchedulerDynamicEditException {
+    MockRM newMockRM = setupSchedulerInstance();
+    CapacityScheduler newCS =
+        (CapacityScheduler) newMockRM.getResourceScheduler();
+
+    try {
+      CapacitySchedulerConfiguration conf = newCS.getConfiguration();
+      conf.setShouldFailAutoQueueCreationWhenGuaranteedCapacityExceeded(C,
+          true);
+
+      newCS.reinitialize(conf, newMockRM.getRMContext());
+
+      // Test add one auto created queue dynamically and manually modify
+      // capacity
+      ManagedParentQueue parentQueue = (ManagedParentQueue) newCS.getQueue("c");
+      AutoCreatedLeafQueue c1 = new AutoCreatedLeafQueue(newCS, "c1",
+          parentQueue);
+      newCS.addQueue(c1);
+      c1.setEntitlement(new QueueEntitlement(0.5f, 1f));
+
+      AutoCreatedLeafQueue c2 = new AutoCreatedLeafQueue(newCS, "c2",
+          parentQueue);
+      newCS.addQueue(c2);
+      c2.setEntitlement(new QueueEntitlement(0.5f, 1f));
+
+      try {
+        AutoCreatedLeafQueue c3 = new AutoCreatedLeafQueue(newCS, "c3",
+            parentQueue);
+        newCS.addQueue(c3);
+        fail("Expected exception for auto queue creation failure");
+      } catch (SchedulerDynamicEditException e) {
+        //expected exception
+      }
+    } finally {
+      if (newMockRM != null) {
+        ((CapacityScheduler) newMockRM.getResourceScheduler()).stop();
+        newMockRM.stop();
+      }
+    }
+  }
+
+  private List<UserGroupMappingPlacementRule.QueueMapping> setupQueueMapping(
+      CapacityScheduler newCS, String user, String parentQueue, String queue) {
+    List<UserGroupMappingPlacementRule.QueueMapping> queueMappings =
+        new ArrayList<>();
+    queueMappings.add(new UserGroupMappingPlacementRule.QueueMapping(
+        UserGroupMappingPlacementRule.QueueMapping.MappingType.USER, user,
+        getQueueMapping(parentQueue, queue)));
+    newCS.getConfiguration().setQueueMappings(queueMappings);
+    return queueMappings;
+  }
+
+  private MockRM setupSchedulerInstance() {
+    CapacitySchedulerConfiguration conf = new CapacitySchedulerConfiguration();
+    setupQueueConfiguration(conf);
+    conf.setClass(YarnConfiguration.RM_SCHEDULER, CapacityScheduler.class,
+        ResourceScheduler.class);
+
+    List<String> queuePlacementRules = new ArrayList<String>();
+    queuePlacementRules.add(YarnConfiguration.USER_GROUP_PLACEMENT_RULE);
+    conf.setQueuePlacementRules(queuePlacementRules);
+
+    setupQueueMappings(conf);
+
+    MockRM newMockRM = new MockRM(conf);
+    return newMockRM;
+  }
+
+  void checkQueueCapacities(CapacityScheduler newCS, float capacityC,
+      float capacityD) {
+    CSQueue rootQueue = newCS.getRootQueue();
+    CSQueue queueC = tcs.findQueue(rootQueue, C);
+    CSQueue queueD = tcs.findQueue(rootQueue, D);
+    CSQueue queueC1 = tcs.findQueue(queueC, C1);
+    CSQueue queueC2 = tcs.findQueue(queueC, C2);
+    CSQueue queueC3 = tcs.findQueue(queueC, C3);
+
+    float capC = capacityC / 100.0f;
+    float capD = capacityD / 100.0f;
+
+    tcs.checkQueueCapacity(queueC, capC, capC, 1.0f, 1.0f);
+    tcs.checkQueueCapacity(queueD, capD, capD, 1.0f, 1.0f);
+    tcs.checkQueueCapacity(queueC1, C1_CAPACITY / 100.0f,
+        (C1_CAPACITY / 100.0f) * capC, 1.0f, 1.0f);
+    tcs.checkQueueCapacity(queueC2, C2_CAPACITY / 100.0f,
+        (C2_CAPACITY / 100.0f) * capC, 1.0f, 1.0f);
+
+    if (queueC3 != null) {
+      ManagedParentQueue parentQueue = (ManagedParentQueue) queueC;
+      QueueCapacities cap =
+          parentQueue.getLeafQueueTemplate().getQueueCapacities();
+      tcs.checkQueueCapacity(queueC3, cap.getCapacity(),
+          (cap.getCapacity()) * capC, 1.0f, 1.0f);
+    }
+  }
+
+  ApplicationAttemptId submitApp(CapacityScheduler newCS, String user,
+      String queue, String parentQueue) {
+    ApplicationId appId = BuilderUtils.newApplicationId(1, 1);
+    SchedulerEvent addAppEvent = new AppAddedSchedulerEvent(appId, queue, user,
+        new ApplicationPlacementContext(queue, parentQueue));
+    ApplicationAttemptId appAttemptId = BuilderUtils.newApplicationAttemptId(
+        appId, 1);
+    SchedulerEvent addAttemptEvent = new AppAttemptAddedSchedulerEvent(
+        appAttemptId, false);
+    newCS.handle(addAppEvent);
+    newCS.handle(addAttemptEvent);
+    return appAttemptId;
+  }
+}