/**
* 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.hdfs.server.namenode.metrics;
import java.io.IOException;
import java.util.Random;
import java.io.DataInputStream;
import junit.framework.TestCase;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.hdfs.DFSTestUtil;
import org.apache.hadoop.hdfs.DistributedFileSystem;
import org.apache.hadoop.hdfs.MiniDFSCluster;
import org.apache.hadoop.hdfs.protocol.LocatedBlock;
import org.apache.hadoop.hdfs.server.namenode.FSNamesystem;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.hdfs.server.namenode.NameNode;
import org.apache.hadoop.metrics2.MetricsSource;
import org.apache.hadoop.metrics2.MetricsRecordBuilder;
import static org.apache.hadoop.test.MetricsAsserts.*;
/**
* Test for metrics published by the Namenode
*/
public class TestNameNodeMetrics extends TestCase {
private static final Configuration CONF = new Configuration();
private static final int DFS_REPLICATION_INTERVAL = 1;
private static final Path TEST_ROOT_DIR_PATH =
new Path(System.getProperty("test.build.data", "build/test/data"));
// Number of datanodes in the cluster
private static final int DATANODE_COUNT = 3;
static {
CONF.setLong("dfs.block.size", 100);
CONF.setInt("io.bytes.per.checksum", 1);
CONF.setLong("dfs.heartbeat.interval", DFS_REPLICATION_INTERVAL);
CONF.setInt("dfs.replication.interval", DFS_REPLICATION_INTERVAL);
}
private MiniDFSCluster cluster;
private MetricsSource fsnMetrics;
private DistributedFileSystem fs;
private Random rand = new Random();
private FSNamesystem namesystem;
private NameNodeInstrumentation nnMetrics;
private static Path getTestPath(String fileName) {
return new Path(TEST_ROOT_DIR_PATH, fileName);
}
@Override
protected void setUp() throws Exception {
cluster = new MiniDFSCluster(CONF, DATANODE_COUNT, true, null);
cluster.waitActive();
namesystem = cluster.getNameNode().getNamesystem();
fs = (DistributedFileSystem) cluster.getFileSystem();
nnMetrics = NameNode.getNameNodeMetrics();
fsnMetrics = namesystem;
}
@Override
protected void tearDown() throws Exception {
cluster.shutdown();
}
/** create a file with a length of <code>fileLen</code> */
private void createFile(Path file, long fileLen, short replicas) throws IOException {
DFSTestUtil.createFile(fs, file, fileLen, replicas, rand.nextLong());
}
private void updateMetrics() throws Exception {
// Wait for metrics update (corresponds to dfs.replication.interval
// for some block related metrics to get updated)
Thread.sleep(1000);
}
private void readFile(FileSystem fileSys,Path name) throws IOException {
//Just read file so that getNumBlockLocations are incremented
DataInputStream stm = fileSys.open(name);
byte [] buffer = new byte[4];
stm.read(buffer,0,4);
stm.close();
}
/**
* Test that capacity metrics are exported and pass
* basic sanity tests.
*/
public void testCapacityMetrics() throws Exception {
MetricsRecordBuilder rb = getMetrics(fsnMetrics);
long capacityTotal = getLongGauge("CapacityTotal", rb);
assert(capacityTotal != 0);
long capacityUsed = getLongGauge("CapacityUsed", rb);
long capacityRemaining =
getLongGauge("CapacityRemaining", rb);
long capacityUsedNonDFS =
getLongGauge("CapacityUsedNonDFS", rb);
assert(capacityUsed + capacityRemaining + capacityUsedNonDFS ==
capacityTotal);
}
/** Test metrics associated with addition of a file */
public void testFileAdd() throws Exception {
// Add files with 32 blocks
final Path file = getTestPath("testFileAdd");
createFile(file, 3200, (short)3);
final long blockCount = 32;
int blockCapacity = namesystem.getBlockCapacity();
updateMetrics();
assertGauge("BlockCapacity", blockCapacity, fsnMetrics);
// File create operations is 1
// Number of files created is depth of <code>file</code> path
MetricsRecordBuilder rb = getMetrics(nnMetrics);
assertCounter("CreateFileOps", 1, rb);
assertCounter("FilesCreated", file.depth(), rb);
// Blocks are stored in a hashmap. Compute its capacity, which
// doubles every time the number of entries reach the threshold.
int threshold = (int)(blockCapacity * FSNamesystem.DEFAULT_MAP_LOAD_FACTOR);
while (threshold < blockCount) {
blockCapacity <<= 1;
}
updateMetrics();
long filesTotal = file.depth() + 1; // Add 1 for root
rb = getMetrics(fsnMetrics);
assertGauge("FilesTotal", filesTotal, rb);
assertGauge("BlocksTotal", blockCount, rb);
assertGauge("BlockCapacity", blockCapacity, rb);
fs.delete(file, true);
filesTotal--; // reduce the filecount for deleted file
// Wait for more than DATANODE_COUNT replication intervals to ensure all
// the blocks pending deletion are sent for deletion to the datanodes.
Thread.sleep(DFS_REPLICATION_INTERVAL * (DATANODE_COUNT + 1) * 1000);
updateMetrics();
rb = getMetrics(fsnMetrics);
assertGauge("FilesTotal", filesTotal, rb);
assertGauge("PendingDeletionBlocks", 0L, rb);
// Delete file operations and number of files deleted must be 1
rb = getMetrics(nnMetrics);
assertCounter("DeleteFileOps", 1, rb);
assertCounter("FilesDeleted", 1, rb);
}
/** Corrupt a block and ensure metrics reflects it */
public void testCorruptBlock() throws Exception {
fs.delete(new Path("/"), true);
// Create a file with single block with two replicas
final Path file = getTestPath("testCorruptBlock");
createFile(file, 100, (short)2);
// Corrupt first replica of the block
LocatedBlock block = namesystem.getBlockLocations(file.toString(), 0, 1).get(0);
namesystem.markBlockAsCorrupt(block.getBlock(), block.getLocations()[0]);
updateMetrics();
MetricsRecordBuilder rb = getMetrics(fsnMetrics);
assertGauge("CorruptBlocks", 1L, rb);
assertGauge("PendingReplicationBlocks", 1L, rb);
assertGauge("ScheduledReplicationBlocks", 1L, rb);
fs.delete(file, true);
updateMetrics();
rb = getMetrics(fsnMetrics);
assertGauge("CorruptBlocks", 0L, rb);
assertGauge("PendingReplicationBlocks", 0L, rb);
assertGauge("ScheduledReplicationBlocks", 0L, rb);
}
/** Create excess blocks by reducing the replication factor for
* for a file and ensure metrics reflects it
*/
public void testExcessBlocks() throws Exception {
Path file = getTestPath("testExcessBlocks");
createFile(file, 100, (short)2);
long totalBlocks = 1;
namesystem.setReplication(file.toString(), (short)1);
updateMetrics();
assertGauge("ExcessBlocks", totalBlocks, fsnMetrics);
fs.delete(file, true);
}
/** Test to ensure metrics reflects missing blocks */
public void testMissingBlock() throws Exception {
// Create a file with single block with two replicas
Path file = getTestPath("testMissingBlocks");
createFile(file, 100, (short)1);
// Corrupt the only replica of the block to result in a missing block
LocatedBlock block = namesystem.getBlockLocations(file.toString(), 0, 1).get(0);
namesystem.markBlockAsCorrupt(block.getBlock(), block.getLocations()[0]);
updateMetrics();
MetricsRecordBuilder rb = getMetrics(fsnMetrics);
assertGauge("UnderReplicatedBlocks", 1L, rb);
assertGauge("MissingBlocks", 1L, rb);
fs.delete(file, true);
updateMetrics();
assertGauge("UnderReplicatedBlocks", 0L, fsnMetrics);
}
/**
* Test numGetBlockLocations metric
*
* Test initiates and performs file operations (create,read,close,open file )
* which results in metrics changes. These metrics changes are updated and
* tested for correctness.
*
* create file operation does not increment numGetBlockLocation
* one read file operation increments numGetBlockLocation by 1
*
* @throws IOException in case of an error
*/
public void testGetBlockLocationMetric() throws Exception{
Path file1_Path = new Path(TEST_ROOT_DIR_PATH, "file1.dat");
// When cluster starts first time there are no file (read,create,open)
// operations so metric numGetBlockLocations should be 0.
assertCounter("GetBlockLocations", 0, nnMetrics);
//Perform create file operation
createFile(file1_Path,100,(short)2);
updateMetrics();
//Create file does not change numGetBlockLocations metric
assertCounter("GetBlockLocations", 0, nnMetrics);
// Open and read file operation increments numGetBlockLocations
// Perform read file operation on earlier created file
readFile(fs, file1_Path);
updateMetrics();
// Verify read file operation has incremented numGetBlockLocations by 1
assertCounter("GetBlockLocations", 1, nnMetrics);
// opening and reading file twice will increment numGetBlockLocations by 2
readFile(fs, file1_Path);
readFile(fs, file1_Path);
updateMetrics();
assertCounter("GetBlockLocations", 3, nnMetrics);
// Verify total load metrics, total load = Data Node started.
updateMetrics();
assertGauge("TotalLoad", DATANODE_COUNT, fsnMetrics);
}
}