YARN-10823. Expose all node labels for root without explicit configurations. Contributed by Andras Gyori

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

@@ -77,6 +77,7 @@ import java.util.Set;
 import java.util.concurrent.locks.ReentrantReadWriteLock;
 
 import static org.apache.hadoop.yarn.server.resourcemanager.scheduler.capacity.CapacitySchedulerConfiguration.DOT;
+import static org.apache.hadoop.yarn.server.resourcemanager.scheduler.capacity.CapacitySchedulerConfiguration.ROOT;
 import static org.apache.hadoop.yarn.server.resourcemanager.scheduler.capacity.CapacitySchedulerConfiguration.UNDEFINED;
 
 public abstract class AbstractCSQueue implements CSQueue {
@@ -463,8 +464,13 @@ public abstract class AbstractCSQueue implements CSQueue {
     if (csContext.getCapacitySchedulerQueueManager() != null
         && csContext.getCapacitySchedulerQueueManager()
         .getConfiguredNodeLabels() != null) {
-      this.configuredNodeLabels = csContext.getCapacitySchedulerQueueManager()
+      if (getQueuePath().equals(ROOT)) {
-          .getConfiguredNodeLabels().getLabelsByQueue(getQueuePath());
+        this.configuredNodeLabels = csContext.getCapacitySchedulerQueueManager()
+            .getConfiguredNodeLabels().getAllConfiguredLabels();
+      } else {
+        this.configuredNodeLabels = csContext.getCapacitySchedulerQueueManager()
+            .getConfiguredNodeLabels().getLabelsByQueue(getQueuePath());
+      }
     } else {
       // Fallback to suboptimal but correct logic
       this.configuredNodeLabels = csContext.getConfiguration()

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

@@ -25,6 +25,7 @@ import java.util.HashMap;
 import java.util.HashSet;
 import java.util.Map;
 import java.util.Set;
+import java.util.stream.Collectors;
 
 /**
  * Contains node labels for all queues extracted from configuration properties.
@@ -74,4 +75,19 @@ public class ConfiguredNodeLabels {
       String queuePath, Collection<String> nodeLabels) {
     configuredNodeLabelsByQueue.put(queuePath, new HashSet<>(nodeLabels));
   }
+
+  /**
+   * Get all configured node labels aggregated from each queue.
+   * @return all node labels
+   */
+  public Set<String> getAllConfiguredLabels() {
+    Set<String> nodeLabels = configuredNodeLabelsByQueue.values().stream()
+        .flatMap(Set::stream).collect(Collectors.toSet());
+
+    if (nodeLabels.size() == 0) {
+      nodeLabels = NO_LABEL;
+    }
+
+    return nodeLabels;
+  }
 }

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

@@ -53,6 +53,7 @@ import java.util.concurrent.CyclicBarrier;
 import java.util.concurrent.atomic.AtomicBoolean;
 
 import org.apache.hadoop.thirdparty.com.google.common.collect.ImmutableMap;
+import org.apache.hadoop.util.Sets;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.apache.hadoop.conf.Configuration;
@@ -5216,6 +5217,37 @@ public class TestLeafQueue {
         e.getMaxApplications());
   }
 
+  @Test
+  public void testRootHasAllNodeLabelsOfItsDescendants() throws IOException {
+    CapacitySchedulerConfiguration conf = csConf;
+    String rootChild = root.getChildQueues().get(0).getQueuePath();
+
+    conf.setCapacityByLabel(rootChild, "test", 100);
+    conf.setCapacityByLabel(rootChild + "." + A, "test", 20);
+    conf.setCapacityByLabel(rootChild + "." + B, "test", 40);
+    conf.setCapacityByLabel(rootChild + "." + C, "test", 10);
+    conf.setCapacityByLabel(rootChild + "." + C + "." + C1, "test", 100);
+    conf.setCapacityByLabel(rootChild + "." + D, "test", 30);
+    conf.setCapacityByLabel(rootChild + "." + E, "test", 0);
+
+    conf.setCapacityByLabel(rootChild, "test2", 100);
+    conf.setCapacityByLabel(rootChild + "." + A, "test2", 20);
+    conf.setCapacityByLabel(rootChild + "." + B, "test2", 40);
+    conf.setCapacityByLabel(rootChild + "." + C, "test2", 10);
+    conf.setCapacityByLabel(rootChild + "." + C + "." + C1, "test2", 100);
+    conf.setCapacityByLabel(rootChild + "." + D, "test2", 30);
+    conf.setCapacityByLabel(rootChild + "." + E, "test2", 0);
+
+    cs.getCapacitySchedulerQueueManager().reinitConfiguredNodeLabels(conf);
+    cs.setMaxRunningAppsEnforcer(new CSMaxRunningAppsEnforcer(cs));
+    cs.reinitialize(conf, cs.getRMContext());
+
+    ParentQueue rootQueue = (ParentQueue) cs.getRootQueue();
+
+    Assert.assertEquals(Sets.newHashSet("", "test", "test2"),
+        rootQueue.configuredNodeLabels);
+  }
+
   @After
   public void tearDown() throws Exception {
     if (cs != null) {