/**
* 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;
import static org.junit.Assert.assertTrue;
import static org.junit.Assert.assertFalse;
import java.io.EOFException;
import java.io.File;
import java.io.IOException;
import java.io.RandomAccessFile;
import java.net.URI;
import java.nio.ByteBuffer;
import java.security.PrivilegedExceptionAction;
import java.util.concurrent.TimeoutException;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FSDataInputStream;
import org.apache.hadoop.fs.FSDataOutputStream;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.hdfs.client.HdfsDataInputStream;
import org.apache.hadoop.hdfs.protocol.ClientDatanodeProtocol;
import org.apache.hadoop.hdfs.protocol.DatanodeID;
import org.apache.hadoop.hdfs.protocol.DatanodeInfo;
import org.apache.hadoop.hdfs.protocol.ExtendedBlock;
import org.apache.hadoop.hdfs.protocol.LocatedBlocks;
import org.apache.hadoop.hdfs.protocol.datatransfer.DataTransferProtocol;
import org.apache.hadoop.hdfs.security.token.block.BlockTokenIdentifier;
import org.apache.hadoop.hdfs.server.datanode.SimulatedFSDataset;
import org.apache.hadoop.io.IOUtils;
import org.apache.hadoop.net.unix.DomainSocket;
import org.apache.hadoop.net.unix.TemporarySocketDirectory;
import org.apache.hadoop.security.UserGroupInformation;
import org.apache.hadoop.security.token.Token;
import org.apache.hadoop.util.StringUtils;
import org.apache.hadoop.util.Time;
import org.junit.AfterClass;
import org.junit.Assert;
import org.junit.Assume;
import org.junit.Before;
import org.junit.BeforeClass;
import org.junit.Test;
import static org.hamcrest.CoreMatchers.*;
/**
* Test for short circuit read functionality using {@link BlockReaderLocal}.
* When a block is being read by a client is on the local datanode, instead of
* using {@link DataTransferProtocol} and connect to datanode, the short circuit
* read allows reading the file directly from the files on the local file
* system.
*/
public class TestShortCircuitLocalRead {
private static TemporarySocketDirectory sockDir;
@BeforeClass
public static void init() {
sockDir = new TemporarySocketDirectory();
DomainSocket.disableBindPathValidation();
}
@AfterClass
public static void shutdown() throws IOException {
sockDir.close();
}
@Before
public void before() {
Assume.assumeThat(DomainSocket.getLoadingFailureReason(), equalTo(null));
}
static final long seed = 0xDEADBEEFL;
static final int blockSize = 5120;
boolean simulatedStorage = false;
// creates a file but does not close it
static FSDataOutputStream createFile(FileSystem fileSys, Path name, int repl)
throws IOException {
FSDataOutputStream stm = fileSys.create(name, true,
fileSys.getConf().getInt("io.file.buffer.size", 4096),
(short)repl, blockSize);
return stm;
}
static private void checkData(byte[] actual, int from, byte[] expected,
String message) {
checkData(actual, from, expected, actual.length, message);
}
static private void checkData(byte[] actual, int from, byte[] expected, int len,
String message) {
for (int idx = 0; idx < len; idx++) {
if (expected[from + idx] != actual[idx]) {
Assert.fail(message + " byte " + (from + idx) + " differs. expected "
+ expected[from + idx] + " actual " + actual[idx] +
"\nexpected: " + StringUtils.byteToHexString(expected, from, from + len) +
"\nactual: " + StringUtils.byteToHexString(actual, 0, len));
}
}
}
private static String getCurrentUser() throws IOException {
return UserGroupInformation.getCurrentUser().getShortUserName();
}
/** Check file content, reading as user {@code readingUser} */
static void checkFileContent(URI uri, Path name, byte[] expected,
int readOffset, String readingUser, Configuration conf,
boolean legacyShortCircuitFails)
throws IOException, InterruptedException {
// Ensure short circuit is enabled
DistributedFileSystem fs = getFileSystem(readingUser, uri, conf);
if (legacyShortCircuitFails) {
assertTrue(fs.getClient().useLegacyBlockReaderLocal());
}
FSDataInputStream stm = fs.open(name);
byte[] actual = new byte[expected.length-readOffset];
stm.readFully(readOffset, actual);
checkData(actual, readOffset, expected, "Read 2");
stm.close();
// Now read using a different API.
actual = new byte[expected.length-readOffset];
stm = fs.open(name);
IOUtils.skipFully(stm, readOffset);
//Read a small number of bytes first.
int nread = stm.read(actual, 0, 3);
nread += stm.read(actual, nread, 2);
//Read across chunk boundary
nread += stm.read(actual, nread, 517);
checkData(actual, readOffset, expected, nread, "A few bytes");
//Now read rest of it
while (nread < actual.length) {
int nbytes = stm.read(actual, nread, actual.length - nread);
if (nbytes < 0) {
throw new EOFException("End of file reached before reading fully.");
}
nread += nbytes;
}
checkData(actual, readOffset, expected, "Read 3");
if (legacyShortCircuitFails) {
assertFalse(fs.getClient().useLegacyBlockReaderLocal());
}
stm.close();
}
private static byte [] arrayFromByteBuffer(ByteBuffer buf) {
ByteBuffer alt = buf.duplicate();
alt.clear();
byte[] arr = new byte[alt.remaining()];
alt.get(arr);
return arr;
}
/** Check the file content, reading as user {@code readingUser} */
static void checkFileContentDirect(URI uri, Path name, byte[] expected,
int readOffset, String readingUser, Configuration conf,
boolean legacyShortCircuitFails)
throws IOException, InterruptedException {
// Ensure short circuit is enabled
DistributedFileSystem fs = getFileSystem(readingUser, uri, conf);
if (legacyShortCircuitFails) {
assertTrue(fs.getClient().useLegacyBlockReaderLocal());
}
HdfsDataInputStream stm = (HdfsDataInputStream)fs.open(name);
ByteBuffer actual = ByteBuffer.allocateDirect(expected.length - readOffset);
IOUtils.skipFully(stm, readOffset);
actual.limit(3);
//Read a small number of bytes first.
int nread = stm.read(actual);
actual.limit(nread + 2);
nread += stm.read(actual);
// Read across chunk boundary
actual.limit(Math.min(actual.capacity(), nread + 517));
nread += stm.read(actual);
checkData(arrayFromByteBuffer(actual), readOffset, expected, nread,
"A few bytes");
//Now read rest of it
actual.limit(actual.capacity());
while (actual.hasRemaining()) {
int nbytes = stm.read(actual);
if (nbytes < 0) {
throw new EOFException("End of file reached before reading fully.");
}
nread += nbytes;
}
checkData(arrayFromByteBuffer(actual), readOffset, expected, "Read 3");
if (legacyShortCircuitFails) {
assertFalse(fs.getClient().useLegacyBlockReaderLocal());
}
stm.close();
}
public void doTestShortCircuitReadLegacy(boolean ignoreChecksum, int size,
int readOffset, String shortCircuitUser, String readingUser,
boolean legacyShortCircuitFails) throws IOException, InterruptedException {
doTestShortCircuitReadImpl(ignoreChecksum, size, readOffset,
shortCircuitUser, readingUser, legacyShortCircuitFails);
}
public void doTestShortCircuitRead(boolean ignoreChecksum, int size,
int readOffset) throws IOException, InterruptedException {
String shortCircuitUser = getCurrentUser();
doTestShortCircuitReadImpl(ignoreChecksum, size, readOffset,
null, getCurrentUser(), false);
}
/**
* Test that file data can be read by reading the block file
* directly from the local store.
*/
public void doTestShortCircuitReadImpl(boolean ignoreChecksum, int size,
int readOffset, String shortCircuitUser, String readingUser,
boolean legacyShortCircuitFails) throws IOException, InterruptedException {
Configuration conf = new Configuration();
conf.setBoolean(DFSConfigKeys.DFS_CLIENT_READ_SHORTCIRCUIT_KEY, true);
conf.setBoolean(DFSConfigKeys.DFS_CLIENT_READ_SHORTCIRCUIT_SKIP_CHECKSUM_KEY,
ignoreChecksum);
conf.set(DFSConfigKeys.DFS_DOMAIN_SOCKET_PATH_KEY,
new File(sockDir.getDir(),
"TestShortCircuitLocalRead._PORT.sock").getAbsolutePath());
if (shortCircuitUser != null) {
conf.set(DFSConfigKeys.DFS_BLOCK_LOCAL_PATH_ACCESS_USER_KEY,
shortCircuitUser);
conf.setBoolean(DFSConfigKeys.DFS_CLIENT_USE_LEGACY_BLOCKREADERLOCAL, true);
}
if (simulatedStorage) {
SimulatedFSDataset.setFactory(conf);
}
MiniDFSCluster cluster = new MiniDFSCluster.Builder(conf).numDataNodes(1)
.format(true).build();
FileSystem fs = cluster.getFileSystem();
try {
// check that / exists
Path path = new Path("/");
assertTrue("/ should be a directory", fs.getFileStatus(path)
.isDirectory() == true);
// create a new file in home directory. Do not close it.
byte[] fileData = AppendTestUtil.randomBytes(seed, size);
Path file1 = fs.makeQualified(new Path("filelocal.dat"));
FSDataOutputStream stm = createFile(fs, file1, 1);
stm.write(fileData);
stm.close();
URI uri = cluster.getURI();
checkFileContent(uri, file1, fileData, readOffset, readingUser, conf,
legacyShortCircuitFails);
checkFileContentDirect(uri, file1, fileData, readOffset, readingUser,
conf, legacyShortCircuitFails);
} finally {
fs.close();
cluster.shutdown();
}
}
@Test(timeout=10000)
public void testFileLocalReadNoChecksum() throws Exception {
doTestShortCircuitRead(true, 3*blockSize+100, 0);
}
@Test(timeout=10000)
public void testFileLocalReadChecksum() throws Exception {
doTestShortCircuitRead(false, 3*blockSize+100, 0);
}
@Test(timeout=10000)
public void testSmallFileLocalRead() throws Exception {
doTestShortCircuitRead(false, 13, 0);
doTestShortCircuitRead(false, 13, 5);
doTestShortCircuitRead(true, 13, 0);
doTestShortCircuitRead(true, 13, 5);
}
@Test(timeout=10000)
public void testLocalReadLegacy() throws Exception {
doTestShortCircuitReadLegacy(true, 13, 0, getCurrentUser(),
getCurrentUser(), false);
}
/**
* Try a short circuit from a reader that is not allowed to
* to use short circuit. The test ensures reader falls back to non
* shortcircuit reads when shortcircuit is disallowed.
*/
@Test(timeout=10000)
public void testLocalReadFallback() throws Exception {
doTestShortCircuitReadLegacy(true, 13, 0, getCurrentUser(), "notallowed", true);
}
@Test(timeout=10000)
public void testReadFromAnOffset() throws Exception {
doTestShortCircuitRead(false, 3*blockSize+100, 777);
doTestShortCircuitRead(true, 3*blockSize+100, 777);
}
@Test(timeout=10000)
public void testLongFile() throws Exception {
doTestShortCircuitRead(false, 10*blockSize+100, 777);
doTestShortCircuitRead(true, 10*blockSize+100, 777);
}
private ClientDatanodeProtocol getProxy(UserGroupInformation ugi,
final DatanodeID dnInfo, final Configuration conf) throws IOException,
InterruptedException {
return ugi.doAs(new PrivilegedExceptionAction<ClientDatanodeProtocol>() {
@Override
public ClientDatanodeProtocol run() throws Exception {
return DFSUtil.createClientDatanodeProtocolProxy(dnInfo, conf, 60000,
false);
}
});
}
private static DistributedFileSystem getFileSystem(String user, final URI uri,
final Configuration conf) throws InterruptedException, IOException {
UserGroupInformation ugi = UserGroupInformation.createRemoteUser(user);
return ugi.doAs(new PrivilegedExceptionAction<DistributedFileSystem>() {
@Override
public DistributedFileSystem run() throws Exception {
return (DistributedFileSystem)FileSystem.get(uri, conf);
}
});
}
@Test(timeout=10000)
public void testDeprecatedGetBlockLocalPathInfoRpc()
throws IOException, InterruptedException {
final Configuration conf = new Configuration();
MiniDFSCluster cluster = new MiniDFSCluster.Builder(conf).numDataNodes(1)
.format(true).build();
cluster.waitActive();
FileSystem fs = cluster.getFileSystem();
try {
DFSTestUtil.createFile(fs, new Path("/tmp/x"), 16, (short) 1, 23);
LocatedBlocks lb = cluster.getNameNode().getRpcServer()
.getBlockLocations("/tmp/x", 0, 16);
// Create a new block object, because the block inside LocatedBlock at
// namenode is of type BlockInfo.
ExtendedBlock blk = new ExtendedBlock(lb.get(0).getBlock());
Token<BlockTokenIdentifier> token = lb.get(0).getBlockToken();
final DatanodeInfo dnInfo = lb.get(0).getLocations()[0];
ClientDatanodeProtocol proxy =
DFSUtil.createClientDatanodeProtocolProxy(dnInfo, conf, 60000, false);
try {
proxy.getBlockLocalPathInfo(blk, token);
Assert.fail("The call should have failed as this user "
+ " is not allowed to call getBlockLocalPathInfo");
} catch (IOException ex) {
Assert.assertTrue(ex.getMessage().contains(
"not allowed to call getBlockLocalPathInfo"));
}
} finally {
fs.close();
cluster.shutdown();
}
}
@Test(timeout=10000)
public void testSkipWithVerifyChecksum() throws IOException {
int size = blockSize;
Configuration conf = new Configuration();
conf.setBoolean(DFSConfigKeys.DFS_CLIENT_READ_SHORTCIRCUIT_KEY, true);
conf.setBoolean(DFSConfigKeys.DFS_CLIENT_READ_SHORTCIRCUIT_SKIP_CHECKSUM_KEY, false);
conf.set(DFSConfigKeys.DFS_DOMAIN_SOCKET_PATH_KEY,
"/tmp/testSkipWithVerifyChecksum._PORT");
DomainSocket.disableBindPathValidation();
if (simulatedStorage) {
SimulatedFSDataset.setFactory(conf);
}
MiniDFSCluster cluster = new MiniDFSCluster.Builder(conf).numDataNodes(1)
.format(true).build();
FileSystem fs = cluster.getFileSystem();
try {
// check that / exists
Path path = new Path("/");
assertTrue("/ should be a directory", fs.getFileStatus(path)
.isDirectory() == true);
byte[] fileData = AppendTestUtil.randomBytes(seed, size*3);
// create a new file in home directory. Do not close it.
Path file1 = new Path("filelocal.dat");
FSDataOutputStream stm = createFile(fs, file1, 1);
// write to file
stm.write(fileData);
stm.close();
// now test the skip function
FSDataInputStream instm = fs.open(file1);
byte[] actual = new byte[fileData.length];
// read something from the block first, otherwise BlockReaderLocal.skip()
// will not be invoked
int nread = instm.read(actual, 0, 3);
long skipped = 2*size+3;
instm.seek(skipped);
nread = instm.read(actual, (int)(skipped + nread), 3);
instm.close();
} finally {
fs.close();
cluster.shutdown();
}
}
@Test
public void testHandleTruncatedBlockFile() throws IOException {
MiniDFSCluster cluster = null;
HdfsConfiguration conf = new HdfsConfiguration();
conf.setBoolean(DFSConfigKeys.DFS_CLIENT_READ_SHORTCIRCUIT_KEY, true);
conf.setBoolean(DFSConfigKeys.DFS_CLIENT_READ_SHORTCIRCUIT_SKIP_CHECKSUM_KEY, false);
conf.set(DFSConfigKeys.DFS_DOMAIN_SOCKET_PATH_KEY,
"/tmp/testHandleTruncatedBlockFile._PORT");
conf.set(DFSConfigKeys.DFS_CHECKSUM_TYPE_KEY, "CRC32C");
final Path TEST_PATH = new Path("/a");
final Path TEST_PATH2 = new Path("/b");
final long RANDOM_SEED = 4567L;
final long RANDOM_SEED2 = 4568L;
FSDataInputStream fsIn = null;
final int TEST_LENGTH = 3456;
try {
cluster = new MiniDFSCluster.Builder(conf).numDataNodes(1).build();
cluster.waitActive();
FileSystem fs = cluster.getFileSystem();
DFSTestUtil.createFile(fs, TEST_PATH,
TEST_LENGTH, (short)1, RANDOM_SEED);
DFSTestUtil.createFile(fs, TEST_PATH2,
TEST_LENGTH, (short)1, RANDOM_SEED2);
fsIn = cluster.getFileSystem().open(TEST_PATH2);
byte original[] = new byte[TEST_LENGTH];
IOUtils.readFully(fsIn, original, 0, TEST_LENGTH);
fsIn.close();
fsIn = null;
try {
DFSTestUtil.waitReplication(fs, TEST_PATH, (short)1);
} catch (InterruptedException e) {
Assert.fail("unexpected InterruptedException during " +
"waitReplication: " + e);
} catch (TimeoutException e) {
Assert.fail("unexpected TimeoutException during " +
"waitReplication: " + e);
}
ExtendedBlock block = DFSTestUtil.getFirstBlock(fs, TEST_PATH);
File dataFile = MiniDFSCluster.getBlockFile(0, block);
cluster.shutdown();
cluster = null;
RandomAccessFile raf = null;
try {
raf = new RandomAccessFile(dataFile, "rw");
raf.setLength(0);
} finally {
if (raf != null) raf.close();
}
cluster = new MiniDFSCluster.Builder(conf).numDataNodes(1).format(false).build();
cluster.waitActive();
fs = cluster.getFileSystem();
fsIn = fs.open(TEST_PATH);
try {
byte buf[] = new byte[100];
fsIn.seek(2000);
fsIn.readFully(buf, 0, buf.length);
Assert.fail("shouldn't be able to read from corrupt 0-length " +
"block file.");
} catch (IOException e) {
DFSClient.LOG.error("caught exception ", e);
}
fsIn.close();
fsIn = null;
// We should still be able to read the other file.
// This is important because it indicates that we detected that the
// previous block was corrupt, rather than blaming the problem on
// communication.
fsIn = fs.open(TEST_PATH2);
byte buf[] = new byte[original.length];
fsIn.readFully(buf, 0, buf.length);
TestBlockReaderLocal.assertArrayRegionsEqual(original, 0, buf, 0,
original.length);
fsIn.close();
fsIn = null;
} finally {
if (fsIn != null) fsIn.close();
if (cluster != null) cluster.shutdown();
}
}
/**
* Test to run benchmarks between short circuit read vs regular read with
* specified number of threads simultaneously reading.
* <br>
* Run this using the following command:
* bin/hadoop --config confdir \
* org.apache.hadoop.hdfs.TestShortCircuitLocalRead \
* <shortcircuit on?> <checsum on?> <Number of threads>
*/
public static void main(String[] args) throws Exception {
if (args.length != 3) {
System.out.println("Usage: test shortcircuit checksum threadCount");
System.exit(1);
}
boolean shortcircuit = Boolean.valueOf(args[0]);
boolean checksum = Boolean.valueOf(args[1]);
int threadCount = Integer.valueOf(args[2]);
// Setup create a file
final Configuration conf = new Configuration();
conf.setBoolean(DFSConfigKeys.DFS_CLIENT_READ_SHORTCIRCUIT_KEY, shortcircuit);
conf.set(DFSConfigKeys.DFS_DOMAIN_SOCKET_PATH_KEY,
"/tmp/TestShortCircuitLocalRead._PORT");
conf.setBoolean(DFSConfigKeys.DFS_CLIENT_READ_SHORTCIRCUIT_SKIP_CHECKSUM_KEY,
checksum);
//Override fileSize and DATA_TO_WRITE to much larger values for benchmark test
int fileSize = 1000 * blockSize + 100; // File with 1000 blocks
final byte [] dataToWrite = AppendTestUtil.randomBytes(seed, fileSize);
// create a new file in home directory. Do not close it.
final Path file1 = new Path("filelocal.dat");
final FileSystem fs = FileSystem.get(conf);
FSDataOutputStream stm = createFile(fs, file1, 1);
stm.write(dataToWrite);
stm.close();
long start = Time.now();
final int iteration = 20;
Thread[] threads = new Thread[threadCount];
for (int i = 0; i < threadCount; i++) {
threads[i] = new Thread() {
@Override
public void run() {
for (int i = 0; i < iteration; i++) {
try {
String user = getCurrentUser();
checkFileContent(fs.getUri(), file1, dataToWrite, 0, user, conf,
true);
} catch (IOException e) {
e.printStackTrace();
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
};
}
for (int i = 0; i < threadCount; i++) {
threads[i].start();
}
for (int i = 0; i < threadCount; i++) {
threads[i].join();
}
long end = Time.now();
System.out.println("Iteration " + iteration + " took " + (end - start));
fs.delete(file1, false);
}
}