YARN-10442. RM should make sure node label file highly available. (#2390)

* YARN-10442. RM should make sure node label file highly available.

* YARN-10442. Corrected method name.
            Added license header for file TestNodeLabelFileReplication.java
            Added Test code.

* YARN-10442. Changed property name and log.

* YARN-10442. Changed default replication for FS store file.

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

@@ -4076,6 +4076,11 @@ public class YarnConfiguration extends Configuration {
   public static final String FS_NODE_LABELS_STORE_ROOT_DIR = NODE_LABELS_PREFIX
       + "fs-store.root-dir";
 
+  /** FS store file replication. */
+  public static final String FS_STORE_FILE_REPLICATION = YARN_PREFIX
+      + "fs-store.file.replication";
+  public static final int DEFAULT_FS_STORE_FILE_REPLICATION = 0;
+
   /**
    * Node-attribute configurations.
    */

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-common/src/main/java/org/apache/hadoop/yarn/nodelabels/store/AbstractFSNodeStore.java

@@ -27,6 +27,7 @@ import org.apache.hadoop.fs.LocalFileSystem;
 import org.apache.hadoop.fs.Path;
 import org.apache.hadoop.io.IOUtils;
 import org.apache.hadoop.yarn.nodelabels.store.op.FSNodeStoreLogOp;
+import org.apache.hadoop.yarn.conf.YarnConfiguration;
 import org.apache.hadoop.yarn.nodelabels.store.FSStoreOpHandler.StoreType;
 
 import java.io.EOFException;
@@ -47,6 +48,7 @@ public abstract class AbstractFSNodeStore<M> {
   private FSDataOutputStream editlogOs;
 
   private Path editLogPath;
+  private int replication;
   private StoreSchema schema;
 
   protected M manager;
@@ -65,6 +67,8 @@ public abstract class AbstractFSNodeStore<M> {
     initFileSystem(conf);
     // mkdir of root dir path
     fs.mkdirs(fsWorkingPath);
+    this.replication = conf.getInt(YarnConfiguration.FS_STORE_FILE_REPLICATION,
+        YarnConfiguration.DEFAULT_FS_STORE_FILE_REPLICATION);
     LOG.info("Created store directory :" + fsWorkingPath);
   }
 
@@ -162,6 +166,7 @@ public abstract class AbstractFSNodeStore<M> {
       StoreOp op = FSStoreOpHandler.getMirrorOp(storeType);
       op.write(os, manager);
     }
+    checkAvailability(writingMirrorPath);
     // Move mirror to mirror.old
     if (fs.exists(mirrorPath)) {
       fs.delete(oldMirrorPath, false);
@@ -178,11 +183,27 @@ public abstract class AbstractFSNodeStore<M> {
     // create a new editlog file
     editlogOs = fs.create(editLogPath, true);
     editlogOs.close();
-
+    checkAvailability(editLogPath);
     LOG.info("Finished write mirror at:" + mirrorPath.toString());
     LOG.info("Finished create editlog file at:" + editLogPath.toString());
   }
 
+  /**
+   * Make sure replica is highly available. It will avoid setting replication,
+   * if the value configured for
+   * {@link YarnConfiguration#FS_STORE_FILE_REPLICATION} is 0.
+   */
+  private void checkAvailability(Path file) throws IOException {
+    try {
+      if (replication != 0
+          && fs.getFileStatus(file).getReplication() < replication) {
+        fs.setReplication(file, (short) replication);
+      }
+    } catch (UnsupportedOperationException e) {
+      LOG.error("Failed set replication for a file : {}", file);
+    }
+  }
+
   protected void loadManagerFromEditLog(Path editPath) throws IOException {
     if (!fs.exists(editPath)) {
       return;

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

@@ -3804,6 +3804,14 @@
     <value>org.apache.hadoop.yarn.nodelabels.FileSystemNodeLabelsStore</value>
   </property>
 
+  <property>
+    <description>The replication factor for the FS store
+     files. Default value is 0, means it will use file system
+      default replication.</description>
+    <name>yarn.fs-store.file.replication</name>
+    <value>0</value>
+  </property>
+
   <property>
     <description>
       Enable the CSRF filter for the RM web app

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

@@ -0,0 +1,64 @@
+/**
+ * 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.nodelabels;
+
+import java.io.IOException;
+
+import org.apache.hadoop.conf.Configuration;
+import org.apache.hadoop.fs.FileSystem;
+import org.apache.hadoop.fs.Path;
+import org.apache.hadoop.hdfs.MiniDFSCluster;
+import org.apache.hadoop.yarn.conf.YarnConfiguration;
+import org.apache.hadoop.yarn.nodelabels.CommonNodeLabelsManager;
+import org.junit.Assert;
+import org.junit.Test;
+
+public class TestNodeLabelFileReplication {
+
+  @Test
+  public void testNodeLabelFileReplication() throws IOException {
+    int expectedReplication = 10;
+    Configuration conf = new Configuration();
+    conf.setBoolean(YarnConfiguration.NODE_LABELS_ENABLED, true);
+    conf.setInt(YarnConfiguration.FS_STORE_FILE_REPLICATION,
+        expectedReplication);
+    MiniDFSCluster cluster = null;
+    try {
+      cluster = new MiniDFSCluster.Builder(new Configuration()).numDataNodes(1)
+          .build();
+      FileSystem fs = cluster.getFileSystem();
+      String nodeLabelDir = fs.getUri().toString() + "/nodelabel";
+      conf.set(YarnConfiguration.FS_NODE_LABELS_STORE_ROOT_DIR, nodeLabelDir);
+      CommonNodeLabelsManager manager = new CommonNodeLabelsManager();
+      manager.init(conf);
+      manager.start();
+      int fileReplication = fs
+          .getFileStatus(new Path(nodeLabelDir, "nodelabel.mirror"))
+          .getReplication();
+      Assert.assertEquals(
+          "Node label file replication should be " + expectedReplication,
+          expectedReplication, fileReplication);
+      manager.close();
+    } finally {
+      if (cluster != null) {
+        cluster.shutdown();
+      }
+    }
+  }
+}