/**
* 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 static org.apache.hadoop.test.MetricsAsserts.assertCounter;
import static org.apache.hadoop.test.MetricsAsserts.assertGauge;
import static org.apache.hadoop.test.MetricsAsserts.assertQuantileGauges;
import static org.apache.hadoop.test.MetricsAsserts.getMetrics;
import static org.junit.Assert.assertTrue;
import java.io.DataInputStream;
import java.io.IOException;
import java.util.Random;
import org.apache.commons.logging.LogFactory;
import org.apache.commons.logging.impl.Log4JLogger;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Options.Rename;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.hdfs.DFSConfigKeys;
import org.apache.hadoop.hdfs.DFSTestUtil;
import org.apache.hadoop.hdfs.DistributedFileSystem;
import org.apache.hadoop.hdfs.HdfsConfiguration;
import org.apache.hadoop.hdfs.MiniDFSCluster;
import org.apache.hadoop.hdfs.protocol.HdfsConstants.SafeModeAction;
import org.apache.hadoop.hdfs.protocol.LocatedBlock;
import org.apache.hadoop.hdfs.server.blockmanagement.BlockManager;
import org.apache.hadoop.hdfs.server.blockmanagement.BlockManagerTestUtil;
import org.apache.hadoop.hdfs.server.datanode.DataNode;
import org.apache.hadoop.hdfs.server.datanode.DataNodeTestUtils;
import org.apache.hadoop.hdfs.server.namenode.FSNamesystem;
import org.apache.hadoop.hdfs.server.namenode.NameNodeAdapter;
import org.apache.hadoop.metrics2.MetricsRecordBuilder;
import org.apache.hadoop.test.MetricsAsserts;
import org.apache.hadoop.util.Time;
import org.apache.log4j.Level;
import org.junit.After;
import org.junit.Before;
import org.junit.Test;
/**
* Test for metrics published by the Namenode
*/
public class TestNameNodeMetrics {
private static final Configuration CONF = new HdfsConfiguration();
private static final int DFS_REPLICATION_INTERVAL = 1;
private static final Path TEST_ROOT_DIR_PATH =
new Path("/testNameNodeMetrics");
private static final String NN_METRICS = "NameNodeActivity";
private static final String NS_METRICS = "FSNamesystem";
// Number of datanodes in the cluster
private static final int DATANODE_COUNT = 3;
private static final int WAIT_GAUGE_VALUE_RETRIES = 20;
// Rollover interval of percentile metrics (in seconds)
private static final int PERCENTILES_INTERVAL = 1;
static {
CONF.setLong(DFSConfigKeys.DFS_BLOCK_SIZE_KEY, 100);
CONF.setInt(DFSConfigKeys.DFS_BYTES_PER_CHECKSUM_KEY, 1);
CONF.setLong(DFSConfigKeys.DFS_HEARTBEAT_INTERVAL_KEY,
DFS_REPLICATION_INTERVAL);
CONF.setInt(DFSConfigKeys.DFS_NAMENODE_REPLICATION_INTERVAL_KEY,
DFS_REPLICATION_INTERVAL);
CONF.set(DFSConfigKeys.DFS_METRICS_PERCENTILES_INTERVALS_KEY,
"" + PERCENTILES_INTERVAL);
// Enable stale DataNodes checking
CONF.setBoolean(DFSConfigKeys.DFS_NAMENODE_AVOID_STALE_DATANODE_FOR_READ_KEY, true);
((Log4JLogger)LogFactory.getLog(MetricsAsserts.class))
.getLogger().setLevel(Level.DEBUG);
}
private MiniDFSCluster cluster;
private DistributedFileSystem fs;
private Random rand = new Random();
private FSNamesystem namesystem;
private BlockManager bm;
private static Path getTestPath(String fileName) {
return new Path(TEST_ROOT_DIR_PATH, fileName);
}
@Before
public void setUp() throws Exception {
cluster = new MiniDFSCluster.Builder(CONF).numDataNodes(DATANODE_COUNT).build();
cluster.waitActive();
namesystem = cluster.getNamesystem();
bm = namesystem.getBlockManager();
fs = (DistributedFileSystem) cluster.getFileSystem();
}
@After
public 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.namenode.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.
*/
@Test (timeout = 1800)
public void testCapacityMetrics() throws Exception {
MetricsRecordBuilder rb = getMetrics(NS_METRICS);
long capacityTotal = MetricsAsserts.getLongGauge("CapacityTotal", rb);
assert(capacityTotal != 0);
long capacityUsed = MetricsAsserts.getLongGauge("CapacityUsed", rb);
long capacityRemaining =
MetricsAsserts.getLongGauge("CapacityRemaining", rb);
long capacityUsedNonDFS =
MetricsAsserts.getLongGauge("CapacityUsedNonDFS", rb);
assert(capacityUsed + capacityRemaining + capacityUsedNonDFS ==
capacityTotal);
}
/** Test metrics indicating the number of stale DataNodes */
@Test
public void testStaleNodes() throws Exception {
// Set two datanodes as stale
for (int i = 0; i < 2; i++) {
DataNode dn = cluster.getDataNodes().get(i);
DataNodeTestUtils.setHeartbeatsDisabledForTests(dn, true);
long staleInterval = CONF.getLong(
DFSConfigKeys.DFS_NAMENODE_STALE_DATANODE_INTERVAL_KEY,
DFSConfigKeys.DFS_NAMENODE_STALE_DATANODE_INTERVAL_DEFAULT);
cluster.getNameNode().getNamesystem().getBlockManager()
.getDatanodeManager().getDatanode(dn.getDatanodeId())
.setLastUpdate(Time.now() - staleInterval - 1);
}
// Let HeartbeatManager to check heartbeat
BlockManagerTestUtil.checkHeartbeat(cluster.getNameNode().getNamesystem()
.getBlockManager());
assertGauge("StaleDataNodes", 2, getMetrics(NS_METRICS));
// Reset stale datanodes
for (int i = 0; i < 2; i++) {
DataNode dn = cluster.getDataNodes().get(i);
DataNodeTestUtils.setHeartbeatsDisabledForTests(dn, false);
cluster.getNameNode().getNamesystem().getBlockManager()
.getDatanodeManager().getDatanode(dn.getDatanodeId())
.setLastUpdate(Time.now());
}
// Let HeartbeatManager to refresh
BlockManagerTestUtil.checkHeartbeat(cluster.getNameNode().getNamesystem()
.getBlockManager());
assertGauge("StaleDataNodes", 0, getMetrics(NS_METRICS));
}
/** Test metrics associated with addition of a file */
@Test
public void testFileAdd() throws Exception {
// Add files with 100 blocks
final Path file = getTestPath("testFileAdd");
createFile(file, 3200, (short)3);
final long blockCount = 32;
int blockCapacity = namesystem.getBlockCapacity();
updateMetrics();
assertGauge("BlockCapacity", blockCapacity, getMetrics(NS_METRICS));
MetricsRecordBuilder rb = getMetrics(NN_METRICS);
// File create operations is 1
// Number of files created is depth of <code>file</code> path
assertCounter("CreateFileOps", 1L, rb);
assertCounter("FilesCreated", (long)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 * BlockManager.DEFAULT_MAP_LOAD_FACTOR);
while (threshold < blockCount) {
blockCapacity <<= 1;
}
updateMetrics();
long filesTotal = file.depth() + 1; // Add 1 for root
rb = getMetrics(NS_METRICS);
assertGauge("FilesTotal", filesTotal, rb);
assertGauge("BlocksTotal", blockCount, rb);
assertGauge("BlockCapacity", blockCapacity, rb);
fs.delete(file, true);
filesTotal--; // reduce the filecount for deleted file
rb = waitForDnMetricValue(NS_METRICS, "FilesTotal", filesTotal);
assertGauge("BlocksTotal", 0L, rb);
assertGauge("PendingDeletionBlocks", 0L, rb);
rb = getMetrics(NN_METRICS);
// Delete file operations and number of files deleted must be 1
assertCounter("DeleteFileOps", 1L, rb);
assertCounter("FilesDeleted", 1L, rb);
}
/** Corrupt a block and ensure metrics reflects it */
@Test
public void testCorruptBlock() throws Exception {
// 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 = NameNodeAdapter.getBlockLocations(
cluster.getNameNode(), file.toString(), 0, 1).get(0);
cluster.getNamesystem().writeLock();
try {
bm.findAndMarkBlockAsCorrupt(block.getBlock(), block.getLocations()[0],
"TEST");
} finally {
cluster.getNamesystem().writeUnlock();
}
updateMetrics();
MetricsRecordBuilder rb = getMetrics(NS_METRICS);
assertGauge("CorruptBlocks", 1L, rb);
assertGauge("PendingReplicationBlocks", 1L, rb);
assertGauge("ScheduledReplicationBlocks", 1L, rb);
fs.delete(file, true);
rb = waitForDnMetricValue(NS_METRICS, "CorruptBlocks", 0L);
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
*/
@Test
public void testExcessBlocks() throws Exception {
Path file = getTestPath("testExcessBlocks");
createFile(file, 100, (short)2);
long totalBlocks = 1;
NameNodeAdapter.setReplication(namesystem, file.toString(), (short)1);
updateMetrics();
MetricsRecordBuilder rb = getMetrics(NS_METRICS);
assertGauge("ExcessBlocks", totalBlocks, rb);
fs.delete(file, true);
}
/** Test to ensure metrics reflects missing blocks */
@Test
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 = NameNodeAdapter.getBlockLocations(
cluster.getNameNode(), file.toString(), 0, 1).get(0);
cluster.getNamesystem().writeLock();
try {
bm.findAndMarkBlockAsCorrupt(block.getBlock(), block.getLocations()[0],
"TEST");
} finally {
cluster.getNamesystem().writeUnlock();
}
updateMetrics();
MetricsRecordBuilder rb = getMetrics(NS_METRICS);
assertGauge("UnderReplicatedBlocks", 1L, rb);
assertGauge("MissingBlocks", 1L, rb);
fs.delete(file, true);
waitForDnMetricValue(NS_METRICS, "UnderReplicatedBlocks", 0L);
}
private void waitForDeletion() throws InterruptedException {
// 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);
}
/**
* Wait for the named gauge value from the metrics source to reach the
* desired value.
*
* There's an initial delay then a spin cycle of sleep and poll. Because
* all the tests use a shared FS instance, these tests are not independent;
* that's why the initial sleep is in there.
*
* @param source metrics source
* @param name gauge name
* @param expected expected value
* @return the last metrics record polled
* @throws Exception if something went wrong.
*/
private MetricsRecordBuilder waitForDnMetricValue(String source,
String name,
long expected)
throws Exception {
MetricsRecordBuilder rb;
long gauge;
//initial wait.
waitForDeletion();
//lots of retries are allowed for slow systems; fast ones will still
//exit early
int retries = (DATANODE_COUNT + 1) * WAIT_GAUGE_VALUE_RETRIES;
rb = getMetrics(source);
gauge = MetricsAsserts.getLongGauge(name, rb);
while (gauge != expected && (--retries > 0)) {
Thread.sleep(DFS_REPLICATION_INTERVAL * 500);
rb = getMetrics(source);
gauge = MetricsAsserts.getLongGauge(name, rb);
}
//at this point the assertion is valid or the retry count ran out
assertGauge(name, expected, rb);
return rb;
}
@Test
public void testRenameMetrics() throws Exception {
Path src = getTestPath("src");
createFile(src, 100, (short)1);
Path target = getTestPath("target");
createFile(target, 100, (short)1);
fs.rename(src, target, Rename.OVERWRITE);
updateMetrics();
MetricsRecordBuilder rb = getMetrics(NN_METRICS);
assertCounter("FilesRenamed", 1L, rb);
assertCounter("FilesDeleted", 1L, rb);
}
/**
* 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
*/
@Test
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 GetBlockLocations should be 0.
assertCounter("GetBlockLocations", 0L, getMetrics(NN_METRICS));
//Perform create file operation
createFile(file1_Path,100,(short)2);
updateMetrics();
//Create file does not change numGetBlockLocations metric
//expect numGetBlockLocations = 0 for previous and current interval
assertCounter("GetBlockLocations", 0L, getMetrics(NN_METRICS));
// Open and read file operation increments GetBlockLocations
// Perform read file operation on earlier created file
readFile(fs, file1_Path);
updateMetrics();
// Verify read file operation has incremented numGetBlockLocations by 1
assertCounter("GetBlockLocations", 1L, getMetrics(NN_METRICS));
// opening and reading file twice will increment numGetBlockLocations by 2
readFile(fs, file1_Path);
readFile(fs, file1_Path);
updateMetrics();
assertCounter("GetBlockLocations", 3L, getMetrics(NN_METRICS));
}
/**
* Test NN checkpoint and transaction-related metrics.
*/
@Test
public void testTransactionAndCheckpointMetrics() throws Exception {
long lastCkptTime = MetricsAsserts.getLongGauge("LastCheckpointTime",
getMetrics(NS_METRICS));
assertGauge("LastCheckpointTime", lastCkptTime, getMetrics(NS_METRICS));
assertGauge("LastWrittenTransactionId", 1L, getMetrics(NS_METRICS));
assertGauge("TransactionsSinceLastCheckpoint", 1L, getMetrics(NS_METRICS));
assertGauge("TransactionsSinceLastLogRoll", 1L, getMetrics(NS_METRICS));
fs.mkdirs(new Path(TEST_ROOT_DIR_PATH, "/tmp"));
updateMetrics();
assertGauge("LastCheckpointTime", lastCkptTime, getMetrics(NS_METRICS));
assertGauge("LastWrittenTransactionId", 2L, getMetrics(NS_METRICS));
assertGauge("TransactionsSinceLastCheckpoint", 2L, getMetrics(NS_METRICS));
assertGauge("TransactionsSinceLastLogRoll", 2L, getMetrics(NS_METRICS));
cluster.getNameNodeRpc().rollEditLog();
updateMetrics();
assertGauge("LastCheckpointTime", lastCkptTime, getMetrics(NS_METRICS));
assertGauge("LastWrittenTransactionId", 4L, getMetrics(NS_METRICS));
assertGauge("TransactionsSinceLastCheckpoint", 4L, getMetrics(NS_METRICS));
assertGauge("TransactionsSinceLastLogRoll", 1L, getMetrics(NS_METRICS));
cluster.getNameNodeRpc().setSafeMode(SafeModeAction.SAFEMODE_ENTER, false);
cluster.getNameNodeRpc().saveNamespace();
cluster.getNameNodeRpc().setSafeMode(SafeModeAction.SAFEMODE_LEAVE, false);
updateMetrics();
long newLastCkptTime = MetricsAsserts.getLongGauge("LastCheckpointTime",
getMetrics(NS_METRICS));
assertTrue(lastCkptTime < newLastCkptTime);
assertGauge("LastWrittenTransactionId", 6L, getMetrics(NS_METRICS));
assertGauge("TransactionsSinceLastCheckpoint", 1L, getMetrics(NS_METRICS));
assertGauge("TransactionsSinceLastLogRoll", 1L, getMetrics(NS_METRICS));
}
/**
* Tests that the sync and block report metrics get updated on cluster
* startup.
*/
@Test
public void testSyncAndBlockReportMetric() throws Exception {
MetricsRecordBuilder rb = getMetrics(NN_METRICS);
// We have one sync when the cluster starts up, just opening the journal
assertCounter("SyncsNumOps", 1L, rb);
// Each datanode reports in when the cluster comes up
assertCounter("BlockReportNumOps", (long)DATANODE_COUNT, rb);
// Sleep for an interval+slop to let the percentiles rollover
Thread.sleep((PERCENTILES_INTERVAL+1)*1000);
// Check that the percentiles were updated
assertQuantileGauges("Syncs1s", rb);
assertQuantileGauges("BlockReport1s", rb);
}
}