YARN-10234. FS-CS converter: don't enable auto-create queue property for root. Contributed by Peter Bacsko

(cherry picked from commit 55fcbcb5c2a096f98f273fda52ae25ecaa1d8bb6)

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/scheduler/fair/converter/FSQueueConverter.java

@@ -27,6 +27,7 @@ import java.util.stream.Collectors;
 
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.yarn.api.records.Resource;
+import org.apache.hadoop.yarn.server.resourcemanager.scheduler.capacity.CapacitySchedulerConfiguration;
 import org.apache.hadoop.yarn.server.resourcemanager.scheduler.fair.ConfigurableResource;
 import org.apache.hadoop.yarn.server.resourcemanager.scheduler.fair.FSLeafQueue;
 import org.apache.hadoop.yarn.server.resourcemanager.scheduler.fair.FSQueue;
@@ -225,7 +226,8 @@ public class FSQueueConverter {
    * @param queueName
    */
   private void emitAutoCreateChildQueue(String queueName, FSQueue queue) {
-    if (autoCreateChildQueues && !queue.getChildQueues().isEmpty()) {
+    if (autoCreateChildQueues && !queue.getChildQueues().isEmpty()
+        && !queueName.equals(CapacitySchedulerConfiguration.ROOT)) {
       capacitySchedulerConfig.setBoolean(PREFIX + queueName +
           ".auto-create-child-queue.enabled", true);
     }

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/test/java/org/apache/hadoop/yarn/server/resourcemanager/scheduler/fair/converter/TestFSConfigToCSConfigConverter.java

@@ -649,6 +649,7 @@ public class TestFSConfigToCSConfigConverter {
     testAutoCreateChildQueuesWithoutPlacementRules(false);
   }
 
+  @SuppressWarnings("checkstyle:linelength")
   private void testAutoCreateChildQueuesWithoutPlacementRules(
       boolean allowUndeclaredPools) throws Exception {
     config = new Configuration(false);
@@ -661,15 +662,27 @@ public class TestFSConfigToCSConfigConverter {
     converter.convert(config);
 
     Configuration convertedConf = converter.getCapacitySchedulerConfig();
-    String property =
+    String rootUserAutoCreate =
+        "yarn.scheduler.capacity.root.users.auto-create-child-queue.enabled";
+    String rootAutoCreate =
         "yarn.scheduler.capacity.root.auto-create-child-queue.enabled";
+    String leafQueueAutoCreate =
+        "yarn.scheduler.capacity.root.users.joe.auto-create-child-queue.enabled";
 
     if (allowUndeclaredPools) {
-      assertEquals("Auto-create queue wasn't enabled", true,
-          convertedConf.getBoolean(property, false));
+      assertEquals("Auto-create queue wasn't enabled for root.users", true,
+          convertedConf.getBoolean(rootUserAutoCreate, false));
+      assertNull("Auto-create queue shouldn't be set for root",
+          convertedConf.get(rootAutoCreate));
+      assertNull("Auto-create queue shouldn't be set for leaf",
+          convertedConf.get(leafQueueAutoCreate));
     } else {
-      assertNull("Auto-create queue shouldn't be set",
-          convertedConf.get(property));
+      assertNull("Auto-create queue shouldn't be set for root.users",
+          convertedConf.get(rootUserAutoCreate));
+      assertNull("Auto-create queue shouldn't be set for root",
+          convertedConf.get(rootAutoCreate));
+      assertNull("Auto-create queue shouldn't be set for leaf",
+          convertedConf.get(leafQueueAutoCreate));
     }
   }
 

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/test/java/org/apache/hadoop/yarn/server/resourcemanager/scheduler/fair/converter/TestFSQueueConverter.java

@@ -316,7 +316,7 @@ public class TestFSQueueConverter {
 
     converter.convertQueueHierarchy(rootQueue);
 
-    Set<String> parentQueues = Sets.newHashSet("root",
+    Set<String> parentQueues = Sets.newHashSet(
         "root.admins",
         "root.users");