hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/datanode/fsdataset/impl/TestLazyPersistReplicaRecovery.java

/**
 * 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,
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 * See the License for the specific language governing permissions and
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package org.apache.hadoop.hdfs.server.datanode.fsdataset.impl;

import org.apache.hadoop.fs.Path;
import org.apache.hadoop.test.GenericTestUtils;
import org.junit.Test;

import java.io.IOException;
import java.util.concurrent.TimeoutException;

import static org.apache.hadoop.fs.StorageType.DEFAULT;
import static org.apache.hadoop.fs.StorageType.RAM_DISK;

public class TestLazyPersistReplicaRecovery extends LazyPersistTestCase {
  @Test
  public void testDnRestartWithSavedReplicas()
      throws IOException, InterruptedException, TimeoutException {

    getClusterBuilder().build();
    final String METHOD_NAME = GenericTestUtils.getMethodName();
    Path path1 = new Path("/" + METHOD_NAME + ".01.dat");

    makeTestFile(path1, BLOCK_SIZE, true);
    ensureFileReplicasOnStorageType(path1, RAM_DISK);

    // Sleep for a short time to allow the lazy writer thread to do its job.
    // However the block replica should not be evicted from RAM_DISK yet.
    Thread.sleep(3 * LAZY_WRITER_INTERVAL_SEC * 1000);
    ensureFileReplicasOnStorageType(path1, RAM_DISK);

    LOG.info("Restarting the DataNode");
    cluster.restartDataNode(0, true);
    cluster.waitActive();
    triggerBlockReport();

    // Ensure that the replica is now on persistent storage.
    ensureFileReplicasOnStorageType(path1, DEFAULT);
  }

  @Test
  public void testDnRestartWithUnsavedReplicas()
      throws IOException, InterruptedException, TimeoutException {

    getClusterBuilder().build();
    FsDatasetTestUtil.stopLazyWriter(cluster.getDataNodes().get(0));

    final String METHOD_NAME = GenericTestUtils.getMethodName();
    Path path1 = new Path("/" + METHOD_NAME + ".01.dat");
    makeTestFile(path1, BLOCK_SIZE, true);
    ensureFileReplicasOnStorageType(path1, RAM_DISK);

    LOG.info("Restarting the DataNode");
    cluster.restartDataNode(0, true);
    cluster.waitActive();

    // Ensure that the replica is still on transient storage.
    ensureFileReplicasOnStorageType(path1, RAM_DISK);
  }
}