YARN-11088. Introduce the config to control the AM allocated to non-exclusive nodes. Contributed by Junfan Zhang

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-api/src/main/java/org/apache/hadoop/yarn/conf/YarnConfiguration.java

@@ -4412,6 +4412,9 @@ public class YarnConfiguration extends Configuration {
   public static final String AM_DEFAULT_NODE_LABEL =
       RM_NODE_LABELS_PREFIX + "am.default-node-label-expression";
 
+  public static final String AM_ALLOW_NON_EXCLUSIVE_ALLOCATION =
+      RM_NODE_LABELS_PREFIX + "am.allow-non-exclusive-allocation";
+
   public static final String RM_NODE_LABELS_PROVIDER_CONFIG =
       RM_NODE_LABELS_PREFIX + "provider";
 

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-common/src/main/resources/yarn-default.xml

@@ -3460,6 +3460,15 @@
     <name>yarn.resourcemanager.node-labels.am.default-node-label-expression</name>
   </property>
 
+  <property>
+    <description>
+      Flag to indicate whether the AM can be allocated to non-exclusive nodes or not.
+      Default is false.
+    </description>
+    <name>yarn.resourcemanager.node-labels.am.allow-non-exclusive-allocation</name>
+    <value>false</value>
+  </property>
+
   <!-- Distributed Node Attributes Configuration -->
   <property>
     <description>

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

@@ -60,6 +60,8 @@ import org.apache.hadoop.yarn.server.utils.BuilderUtils;
 import org.apache.hadoop.yarn.util.resource.ResourceCalculator;
 import org.apache.hadoop.yarn.util.resource.Resources;
 
+import static org.apache.hadoop.yarn.conf.YarnConfiguration.AM_ALLOW_NON_EXCLUSIVE_ALLOCATION;
+
 /**
  * Allocate normal (new) containers, considers locality/label, etc. Using
  * delayed scheduling mechanism to get better locality allocation.
@@ -121,10 +123,9 @@ public class RegularContainerAllocator extends AbstractContainerAllocator {
       return ContainerAllocation.PRIORITY_SKIPPED;
     }
 
-    // AM container allocation doesn't support non-exclusive allocation to
-    // avoid painful of preempt an AM container
     if (schedulingMode == SchedulingMode.IGNORE_PARTITION_EXCLUSIVITY) {
-      if (application.isWaitingForAMContainer()) {
+      if (application.isWaitingForAMContainer() && !rmContext.getYarnConfiguration()
+          .getBoolean(AM_ALLOW_NON_EXCLUSIVE_ALLOCATION, false)) {
         LOG.debug("Skip allocating AM container to app_attempt={},"
             + " don't allow to allocate AM container in non-exclusive mode",
             application.getApplicationAttemptId());

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

@@ -0,0 +1,123 @@
+/**
+ * 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 java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Set;
+
+import org.apache.hadoop.conf.Configuration;
+import org.apache.hadoop.util.Sets;
+import org.apache.hadoop.yarn.api.records.ContainerId;
+import org.apache.hadoop.yarn.api.records.NodeId;
+import org.apache.hadoop.yarn.api.records.NodeLabel;
+import org.apache.hadoop.yarn.conf.YarnConfiguration;
+import org.apache.hadoop.yarn.server.resourcemanager.MockAM;
+import org.apache.hadoop.yarn.server.resourcemanager.MockNM;
+import org.apache.hadoop.yarn.server.resourcemanager.MockRM;
+import org.apache.hadoop.yarn.server.resourcemanager.MockRMAppSubmissionData;
+import org.apache.hadoop.yarn.server.resourcemanager.MockRMAppSubmitter;
+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.recovery.MemoryRMStateStore;
+import org.apache.hadoop.yarn.server.resourcemanager.rmapp.RMApp;
+import org.apache.hadoop.yarn.server.resourcemanager.rmcontainer.RMContainerState;
+import org.apache.hadoop.yarn.server.resourcemanager.scheduler.ResourceScheduler;
+
+import org.junit.Assert;
+import org.junit.Before;
+import org.junit.Test;
+
+import org.apache.hadoop.thirdparty.com.google.common.collect.ImmutableMap;
+
+public class TestAMAllocatedToNonExclusivePartition {
+  private Configuration conf;
+  private RMNodeLabelsManager mgr;
+
+  @Before
+  public void setUp() throws Exception {
+    conf = new YarnConfiguration();
+    conf.setClass(YarnConfiguration.RM_SCHEDULER, CapacityScheduler.class,
+        ResourceScheduler.class);
+    conf.setBoolean(YarnConfiguration.RECOVERY_ENABLED, true);
+    conf.setBoolean(YarnConfiguration.RM_WORK_PRESERVING_RECOVERY_ENABLED, true);
+    conf.set(YarnConfiguration.RM_STORE, MemoryRMStateStore.class.getName());
+    mgr = new NullRMNodeLabelsManager();
+    mgr.init(conf);
+  }
+
+  @SuppressWarnings("unchecked")
+  private <E> Set<E> toSet(E... elements) {
+    Set<E> set = Sets.newHashSet(elements);
+    return set;
+  }
+
+  /**
+   * Test that AM can be allocated to non-exclusive partition when the config
+   * of {@code YarnConfiguration.AM_ALLOW_NON_EXCLUSIVE_ALLOCATION} is true.
+   */
+  @Test
+  public void testAMAllowToNonExclusivePartition() throws Exception {
+    conf.setBoolean(YarnConfiguration.AM_ALLOW_NON_EXCLUSIVE_ALLOCATION, true);
+
+    mgr.addToCluserNodeLabels(
+        Arrays.asList(NodeLabel.newInstance("x", false))
+    );
+    mgr.addLabelsToNode(
+        ImmutableMap.of(NodeId.newInstance("h1", 0), toSet("x"))
+    );
+
+    conf = TestUtils.getConfigurationWithDefaultQueueLabels(conf);
+
+    MockRM rm1 = new MockRM(conf) {
+      @Override
+      public RMNodeLabelsManager createNodeLabelManager() {
+        return mgr;
+      }
+    };
+    rm1.getRMContext().setNodeLabelManager(mgr);
+    rm1.start();
+
+    MockNM nm1 = rm1.registerNode("h1:1234", 8000); // label = x
+
+    MockRMAppSubmissionData data2 =
+        MockRMAppSubmissionData
+            .Builder
+            .createWithMemory(200, rm1)
+            .withAppName("app")
+            .withUser("user")
+            .withAcls(null)
+            .withQueue("c1")
+            .withUnmanagedAM(false)
+            .build();
+
+    RMApp app1 = MockRMAppSubmitter.submit(rm1, data2);
+    // Wait the AM allocated to non-partition node of h1
+    MockAM am1 = MockRM.launchAndRegisterAM(app1, rm1, nm1);
+
+    ContainerId containerId;
+
+    // Request a container and it also should be allocated to non-partition node of h1
+    am1.allocate("*", 1024, 1, new ArrayList<ContainerId>());
+    containerId = ContainerId.newContainerId(am1.getApplicationAttemptId(), 2);
+    Assert.assertTrue(rm1.waitForState(nm1, containerId, RMContainerState.ALLOCATED));
+
+    rm1.close();
+  }
+}