YARN-6917. Queue path is recomputed from scratch on every allocation. Contributed by Eric Payne

(cherry picked from commit 5558792894169425bff054364a1ab4c48b347fb9)

Conflicts:
	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

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

@@ -60,6 +60,7 @@ public abstract class AbstractCSQueue implements CSQueue {
   private static final Log LOG = LogFactory.getLog(AbstractCSQueue.class);  
   CSQueue parent;
   final String queueName;
+  private final String queuePath;
   volatile int numContainers;
   
   final Resource minimumAllocation;
@@ -96,6 +97,8 @@ public abstract class AbstractCSQueue implements CSQueue {
     this.labelManager = cs.getRMContext().getNodeLabelManager();
     this.parent = parent;
     this.queueName = queueName;
+    this.queuePath =
+      ((parent == null) ? "" : (parent.getQueuePath() + ".")) + this.queueName;
     this.resourceCalculator = cs.getResourceCalculator();
     
     // must be called after parent and queueName is set
@@ -122,6 +125,11 @@ public abstract class AbstractCSQueue implements CSQueue {
         queueCapacities,
         parent == null ? null : parent.getQueueCapacities());
   }
+
+  @Override
+  public String getQueuePath() {
+    return queuePath;
+  }
   
   @Override
   public synchronized float getCapacity() {

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

@@ -310,11 +310,6 @@ public class LeafQueue extends AbstractCSQueue {
     allUsersTimesWeights = sumAllUsersTimesWeights();
   }
 
-  @Override
-  public String getQueuePath() {
-    return getParent().getQueuePath() + "." + getQueueName();
-  }
-
   /**
    * Used only by tests.
    */

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

@@ -179,12 +179,6 @@ public class ParentQueue extends AbstractCSQueue {
     }
   }
 
-  @Override
-  public String getQueuePath() {
-    String parentPath = ((parent == null) ? "" : (parent.getQueuePath() + "."));
-    return parentPath + getQueueName();
-  }
-
   @Override
   public synchronized QueueInfo getQueueInfo( 
       boolean includeChildQueues, boolean recursive) {