HDFS-12886. Ignore minReplication for block recovery. Contributed by Lukas Majercak.
(cherry picked from commit 08ff1586d5d3e39f546200f9e696f62ea4cf000d)
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/blockmanagement/BlockManager.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/blockmanagement/BlockManager.java
index 6b7175d..89264c4 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/blockmanagement/BlockManager.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/blockmanagement/BlockManager.java
@@ -1001,6 +1001,13 @@
addExpectedReplicasToPending(lastBlock);
}
completeBlock(lastBlock, iip, false);
+ } else if (pendingRecoveryBlocks.isUnderRecovery(lastBlock)) {
+ // We've just finished recovery for this block, complete
+ // the block forcibly disregarding number of replicas.
+ // This is to ignore minReplication, the block will be closed
+ // and then replicated out.
+ completeBlock(lastBlock, iip, true);
+ updateNeededReconstructions(lastBlock, 1, 0);
}
return committed;
}
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/datanode/TestBlockRecovery.java b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/datanode/TestBlockRecovery.java
index e9bd7a8..07fd4ae 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/datanode/TestBlockRecovery.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/datanode/TestBlockRecovery.java
@@ -19,9 +19,14 @@
package org.apache.hadoop.hdfs.server.datanode;
import org.apache.hadoop.hdfs.AppendTestUtil;
+import org.apache.hadoop.hdfs.DFSClient;
import org.apache.hadoop.hdfs.server.namenode.NameNode;
import org.apache.hadoop.hdfs.server.protocol.SlowDiskReports;
+import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_BLOCK_SIZE_KEY;
+import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_NAMENODE_HEARTBEAT_RECHECK_INTERVAL_KEY;
+import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_NAMENODE_REPLICATION_MIN_KEY;
+import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertTrue;
import static org.junit.Assert.fail;
import static org.mockito.Matchers.any;
@@ -42,6 +47,7 @@
import java.net.InetSocketAddress;
import java.net.URISyntaxException;
import java.util.ArrayList;
+import java.util.Arrays;
import java.util.Collection;
import java.util.HashMap;
import java.util.List;
@@ -1142,4 +1148,81 @@
}
}
}
+
+ /**
+ * Test that block will be recovered even if there are less than the
+ * specified minReplication datanodes involved in its recovery.
+ *
+ * Check that, after recovering, the block will be successfully replicated.
+ */
+ @Test(timeout = 300000L)
+ public void testRecoveryWillIgnoreMinReplication() throws Exception {
+ tearDown(); // Stop the Mocked DN started in startup()
+
+ final int blockSize = 4096;
+ final int numReplicas = 3;
+ final String filename = "/testIgnoreMinReplication";
+ final Path filePath = new Path(filename);
+ Configuration configuration = new HdfsConfiguration();
+ configuration.setInt(DFS_NAMENODE_HEARTBEAT_RECHECK_INTERVAL_KEY, 2000);
+ configuration.setInt(DFS_NAMENODE_REPLICATION_MIN_KEY, 2);
+ configuration.setLong(DFS_BLOCK_SIZE_KEY, blockSize);
+ MiniDFSCluster cluster = null;
+
+ try {
+ cluster = new MiniDFSCluster.Builder(configuration).numDataNodes(5)
+ .build();
+ cluster.waitActive();
+ final DistributedFileSystem dfs = cluster.getFileSystem();
+ final FSNamesystem fsn = cluster.getNamesystem();
+
+ // Create a file and never close the output stream to trigger recovery
+ FSDataOutputStream out = dfs.create(filePath, (short) numReplicas);
+ out.write(AppendTestUtil.randomBytes(0, blockSize));
+ out.hsync();
+
+ DFSClient dfsClient = new DFSClient(new InetSocketAddress("localhost",
+ cluster.getNameNodePort()), configuration);
+ LocatedBlock blk = dfsClient.getNamenode().
+ getBlockLocations(filename, 0, blockSize).
+ getLastLocatedBlock();
+
+ // Kill 2 out of 3 datanodes so that only 1 alive, thus < minReplication
+ List<DatanodeInfo> dataNodes = Arrays.asList(blk.getLocations());
+ assertEquals(dataNodes.size(), numReplicas);
+ for (DatanodeInfo dataNode : dataNodes.subList(0, numReplicas - 1)) {
+ cluster.stopDataNode(dataNode.getName());
+ }
+
+ GenericTestUtils.waitFor(new Supplier<Boolean>() {
+ @Override
+ public Boolean get() {
+ return fsn.getNumDeadDataNodes() == 2;
+ }
+ }, 300, 300000);
+
+ // Make sure hard lease expires to trigger replica recovery
+ cluster.setLeasePeriod(100L, 100L);
+
+ // Wait for recovery to succeed
+ GenericTestUtils.waitFor(new Supplier<Boolean>() {
+ @Override
+ public Boolean get() {
+ try {
+ return dfs.isFileClosed(filePath);
+ } catch (IOException e) {}
+ return false;
+ }
+ }, 300, 300000);
+
+ // Wait for the block to be replicated
+ DFSTestUtil.waitForReplication(cluster, DFSTestUtil.getFirstBlock(
+ dfs, filePath), 1, numReplicas, 0);
+
+ } finally {
+ if (cluster != null) {
+ cluster.shutdown();
+ }
+ }
+ }
}
