HDFS-4213. Add an API to hsync for updating the last block length at the namenode. Contributed by Jing Zhao

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1415799 13f79535-47bb-0310-9956-ffa450edef68
This commit is contained in:
Tsz-wo Sze 2012-11-30 19:24:30 +00:00
parent d866f81edb
commit 571da54179
11 changed files with 231 additions and 46 deletions

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@ -389,6 +389,9 @@ Release 2.0.3-alpha - Unreleased
HDFS-4155. libhdfs implementation of hsync API (Liang Xie via todd)
HDFS-4213. Add an API to hsync for updating the last block length at the
namenode. (Jing Zhao via szetszwo)
IMPROVEMENTS
HDFS-3925. Prettify PipelineAck#toString() for printing to a log

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@ -46,6 +46,7 @@ import org.apache.hadoop.fs.Syncable;
import org.apache.hadoop.fs.UnresolvedLinkException;
import org.apache.hadoop.fs.permission.FsPermission;
import org.apache.hadoop.hdfs.client.HdfsDataOutputStream;
import org.apache.hadoop.hdfs.client.HdfsDataOutputStream.SyncFlag;
import org.apache.hadoop.hdfs.protocol.DSQuotaExceededException;
import org.apache.hadoop.hdfs.protocol.DatanodeInfo;
import org.apache.hadoop.hdfs.protocol.ExtendedBlock;
@ -1487,7 +1488,12 @@ public class DFSOutputStream extends FSOutputSummer implements Syncable {
*/
@Override
public void hflush() throws IOException {
flushOrSync(false);
flushOrSync(false, EnumSet.noneOf(SyncFlag.class));
}
@Override
public void hsync() throws IOException {
hsync(EnumSet.noneOf(SyncFlag.class));
}
/**
@ -1498,17 +1504,35 @@ public class DFSOutputStream extends FSOutputSummer implements Syncable {
* Note that only the current block is flushed to the disk device.
* To guarantee durable sync across block boundaries the stream should
* be created with {@link CreateFlag#SYNC_BLOCK}.
*
* @param syncFlags
* Indicate the semantic of the sync. Currently used to specify
* whether or not to update the block length in NameNode.
*/
@Override
public void hsync() throws IOException {
flushOrSync(true);
public void hsync(EnumSet<SyncFlag> syncFlags) throws IOException {
flushOrSync(true, syncFlags);
}
private void flushOrSync(boolean isSync) throws IOException {
/**
* Flush/Sync buffered data to DataNodes.
*
* @param isSync
* Whether or not to require all replicas to flush data to the disk
* device
* @param syncFlags
* Indicate extra detailed semantic of the flush/sync. Currently
* mainly used to specify whether or not to update the file length in
* the NameNode
* @throws IOException
*/
private void flushOrSync(boolean isSync, EnumSet<SyncFlag> syncFlags)
throws IOException {
dfsClient.checkOpen();
isClosed();
try {
long toWaitFor;
long lastBlockLength = -1L;
boolean updateLength = syncFlags.contains(SyncFlag.UPDATE_LENGTH);
synchronized (this) {
/* Record current blockOffset. This might be changed inside
* flushBuffer() where a partial checksum chunk might be flushed.
@ -1573,12 +1597,19 @@ public class DFSOutputStream extends FSOutputSummer implements Syncable {
waitForAckedSeqno(toWaitFor);
// If any new blocks were allocated since the last flush,
// then persist block locations on namenode.
//
if (persistBlocks.getAndSet(false)) {
if (updateLength) {
synchronized (this) {
if (streamer != null && streamer.block != null) {
lastBlockLength = streamer.block.getNumBytes();
}
}
}
// If 1) any new blocks were allocated since the last flush, or 2) to
// update length in NN is requried, then persist block locations on
// namenode.
if (persistBlocks.getAndSet(false) || updateLength) {
try {
dfsClient.namenode.fsync(src, dfsClient.clientName);
dfsClient.namenode.fsync(src, dfsClient.clientName, lastBlockLength);
} catch (IOException ioe) {
DFSClient.LOG.warn("Unable to persist blocks in hflush for " + src, ioe);
// If we got an error here, it might be because some other thread called

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@ -18,6 +18,7 @@
package org.apache.hadoop.hdfs.client;
import java.io.IOException;
import java.util.EnumSet;
import org.apache.hadoop.classification.InterfaceAudience;
import org.apache.hadoop.classification.InterfaceStability;
@ -56,4 +57,24 @@ public class HdfsDataOutputStream extends FSDataOutputStream {
public synchronized int getCurrentBlockReplication() throws IOException {
return ((DFSOutputStream)getWrappedStream()).getCurrentBlockReplication();
}
/**
* Sync buffered data to DataNodes (flush to disk devices).
*
* @param syncFlags
* Indicate the detailed semantic and actions of the hsync.
* @throws IOException
* @see FSDataOutputStream#hsync()
*/
public void hsync(EnumSet<SyncFlag> syncFlags) throws IOException {
((DFSOutputStream) getWrappedStream()).hsync(syncFlags);
}
public static enum SyncFlag {
/**
* When doing sync to DataNodes, also update the metadata (block
* length) in the NameNode
*/
UPDATE_LENGTH;
}
}

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@ -815,14 +815,15 @@ public interface ClientProtocol {
* The file must be currently open for writing.
* @param src The string representation of the path
* @param client The string representation of the client
*
* @param lastBlockLength The length of the last block (under construction)
* to be reported to NameNode
* @throws AccessControlException permission denied
* @throws FileNotFoundException file <code>src</code> is not found
* @throws UnresolvedLinkException if <code>src</code> contains a symlink.
* @throws IOException If an I/O error occurred
*/
@Idempotent
public void fsync(String src, String client)
public void fsync(String src, String client, long lastBlockLength)
throws AccessControlException, FileNotFoundException,
UnresolvedLinkException, IOException;

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@ -688,7 +688,7 @@ public class ClientNamenodeProtocolServerSideTranslatorPB implements
public FsyncResponseProto fsync(RpcController controller,
FsyncRequestProto req) throws ServiceException {
try {
server.fsync(req.getSrc(), req.getClient());
server.fsync(req.getSrc(), req.getClient(), req.getLastBlockLength());
return VOID_FSYNC_RESPONSE;
} catch (IOException e) {
throw new ServiceException(e);

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@ -659,12 +659,11 @@ public class ClientNamenodeProtocolTranslatorPB implements
}
@Override
public void fsync(String src, String client) throws AccessControlException,
FileNotFoundException, UnresolvedLinkException, IOException {
FsyncRequestProto req = FsyncRequestProto.newBuilder()
.setSrc(src)
.setClient(client)
.build();
public void fsync(String src, String client, long lastBlockLength)
throws AccessControlException, FileNotFoundException,
UnresolvedLinkException, IOException {
FsyncRequestProto req = FsyncRequestProto.newBuilder().setSrc(src)
.setClient(client).setLastBlockLength(lastBlockLength).build();
try {
rpcProxy.fsync(null, req);
} catch (ServiceException e) {

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@ -2979,9 +2979,11 @@ public class FSNamesystem implements Namesystem, FSClusterStats,
/** Persist all metadata about this file.
* @param src The string representation of the path
* @param clientName The string representation of the client
* @param lastBlockLength The length of the last block
* under construction reported from client.
* @throws IOException if path does not exist
*/
void fsync(String src, String clientName)
void fsync(String src, String clientName, long lastBlockLength)
throws IOException, UnresolvedLinkException {
NameNode.stateChangeLog.info("BLOCK* fsync: " + src + " for " + clientName);
writeLock();
@ -2991,6 +2993,9 @@ public class FSNamesystem implements Namesystem, FSClusterStats,
throw new SafeModeException("Cannot fsync file " + src, safeMode);
}
INodeFileUnderConstruction pendingFile = checkLease(src, clientName);
if (lastBlockLength > 0) {
pendingFile.updateLengthOfLastBlock(lastBlockLength);
}
dir.persistBlocks(src, pendingFile);
} finally {
writeUnlock();

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@ -171,4 +171,22 @@ class INodeFileUnderConstruction extends INodeFile implements MutableBlockCollec
setBlock(numBlocks()-1, ucBlock);
return ucBlock;
}
/**
* Update the length for the last block
*
* @param lastBlockLength
* The length of the last block reported from client
* @throws IOException
*/
void updateLengthOfLastBlock(long lastBlockLength) throws IOException {
BlockInfo lastBlock = this.getLastBlock();
assert (lastBlock != null) : "The last block for path "
+ this.getFullPathName() + " is null when updating its length";
assert (lastBlock instanceof BlockInfoUnderConstruction) : "The last block for path "
+ this.getFullPathName()
+ " is not a BlockInfoUnderConstruction when updating its length";
lastBlock.setNumBytes(lastBlockLength);
}
}

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@ -825,8 +825,9 @@ class NameNodeRpcServer implements NamenodeProtocols {
}
@Override // ClientProtocol
public void fsync(String src, String clientName) throws IOException {
namesystem.fsync(src, clientName);
public void fsync(String src, String clientName, long lastBlockLength)
throws IOException {
namesystem.fsync(src, clientName, lastBlockLength);
}
@Override // ClientProtocol

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@ -357,6 +357,7 @@ message SetQuotaResponseProto { // void response
message FsyncRequestProto {
required string src = 1;
required string client = 2;
optional sint64 lastBlockLength = 3 [default = -1];
}
message FsyncResponseProto { // void response

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@ -23,12 +23,14 @@ import static org.junit.Assert.assertTrue;
import java.io.IOException;
import java.io.InterruptedIOException;
import java.util.EnumSet;
import org.apache.commons.logging.impl.Log4JLogger;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FSDataInputStream;
import org.apache.hadoop.fs.FSDataOutputStream;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.hdfs.client.HdfsDataOutputStream.SyncFlag;
import org.apache.hadoop.hdfs.server.datanode.DataNode;
import org.apache.log4j.Level;
import org.junit.Test;
@ -43,15 +45,20 @@ public class TestHFlush {
private final String fName = "hflushtest.dat";
/** The test uses {@link #doTheJob(Configuration, String, long, short)
/**
* The test uses
* {@link #doTheJob(Configuration, String, long, short, boolean, EnumSet)}
* to write a file with a standard block size
*/
@Test
public void hFlush_01() throws IOException {
doTheJob(new HdfsConfiguration(), fName, AppendTestUtil.BLOCK_SIZE, (short)2);
doTheJob(new HdfsConfiguration(), fName, AppendTestUtil.BLOCK_SIZE,
(short) 2, false, EnumSet.noneOf(SyncFlag.class));
}
/** The test uses {@link #doTheJob(Configuration, String, long, short)
/**
* The test uses
* {@link #doTheJob(Configuration, String, long, short, boolean, EnumSet)}
* to write a file with a custom block size so the writes will be
* happening across block' boundaries
*/
@ -64,10 +71,13 @@ public class TestHFlush {
conf.setInt(DFSConfigKeys.DFS_BYTES_PER_CHECKSUM_KEY, customPerChecksumSize);
conf.setLong(DFSConfigKeys.DFS_BLOCK_SIZE_KEY, customBlockSize);
doTheJob(conf, fName, customBlockSize, (short)2);
doTheJob(conf, fName, customBlockSize, (short) 2, false,
EnumSet.noneOf(SyncFlag.class));
}
/** The test uses {@link #doTheJob(Configuration, String, long, short)
/**
* The test uses
* {@link #doTheJob(Configuration, String, long, short, boolean, EnumSet)}
* to write a file with a custom block size so the writes will be
* happening across block's and checksum' boundaries
*/
@ -80,22 +90,106 @@ public class TestHFlush {
conf.setInt(DFSConfigKeys.DFS_BYTES_PER_CHECKSUM_KEY, customPerChecksumSize);
conf.setLong(DFSConfigKeys.DFS_BLOCK_SIZE_KEY, customBlockSize);
doTheJob(conf, fName, customBlockSize, (short)2);
doTheJob(conf, fName, customBlockSize, (short) 2, false,
EnumSet.noneOf(SyncFlag.class));
}
/**
The method starts new cluster with defined Configuration;
creates a file with specified block_size and writes 10 equal sections in it;
it also calls hflush() after each write and throws an IOException in case of
an error.
@param conf cluster configuration
@param fileName of the file to be created and processed as required
@param block_size value to be used for the file's creation
@param replicas is the number of replicas
@throws IOException in case of any errors
* Test hsync (with updating block length in NameNode) while no data is
* actually written yet
*/
@Test
public void hSyncUpdateLength_00() throws IOException {
Configuration conf = new HdfsConfiguration();
MiniDFSCluster cluster = new MiniDFSCluster.Builder(conf).numDataNodes(
2).build();
DistributedFileSystem fileSystem =
(DistributedFileSystem)cluster.getFileSystem();
try {
Path path = new Path(fName);
FSDataOutputStream stm = fileSystem.create(path, true, 4096, (short) 2,
AppendTestUtil.BLOCK_SIZE);
System.out.println("Created file " + path.toString());
((DFSOutputStream) stm.getWrappedStream()).hsync(EnumSet
.of(SyncFlag.UPDATE_LENGTH));
long currentFileLength = fileSystem.getFileStatus(path).getLen();
assertEquals(0L, currentFileLength);
stm.close();
} finally {
fileSystem.close();
cluster.shutdown();
}
}
/**
* The test calls
* {@link #doTheJob(Configuration, String, long, short, boolean, EnumSet)}
* while requiring the semantic of {@link SyncFlag#UPDATE_LENGTH}.
*/
@Test
public void hSyncUpdateLength_01() throws IOException {
doTheJob(new HdfsConfiguration(), fName, AppendTestUtil.BLOCK_SIZE,
(short) 2, true, EnumSet.of(SyncFlag.UPDATE_LENGTH));
}
/**
* The test calls
* {@link #doTheJob(Configuration, String, long, short, boolean, EnumSet)}
* while requiring the semantic of {@link SyncFlag#UPDATE_LENGTH}.
* Similar with {@link #hFlush_02()} , it writes a file with a custom block
* size so the writes will be happening across block' boundaries
*/
@Test
public void hSyncUpdateLength_02() throws IOException {
Configuration conf = new HdfsConfiguration();
int customPerChecksumSize = 512;
int customBlockSize = customPerChecksumSize * 3;
// Modify defaul filesystem settings
conf.setInt(DFSConfigKeys.DFS_BYTES_PER_CHECKSUM_KEY, customPerChecksumSize);
conf.setLong(DFSConfigKeys.DFS_BLOCK_SIZE_KEY, customBlockSize);
doTheJob(conf, fName, customBlockSize, (short) 2, true,
EnumSet.of(SyncFlag.UPDATE_LENGTH));
}
/**
* The test calls
* {@link #doTheJob(Configuration, String, long, short, boolean, EnumSet)}
* while requiring the semantic of {@link SyncFlag#UPDATE_LENGTH}.
* Similar with {@link #hFlush_03()} , it writes a file with a custom block
* size so the writes will be happening across block's and checksum'
* boundaries.
*/
@Test
public void hSyncUpdateLength_03() throws IOException {
Configuration conf = new HdfsConfiguration();
int customPerChecksumSize = 400;
int customBlockSize = customPerChecksumSize * 3;
// Modify defaul filesystem settings
conf.setInt(DFSConfigKeys.DFS_BYTES_PER_CHECKSUM_KEY, customPerChecksumSize);
conf.setLong(DFSConfigKeys.DFS_BLOCK_SIZE_KEY, customBlockSize);
doTheJob(conf, fName, customBlockSize, (short) 2, true,
EnumSet.of(SyncFlag.UPDATE_LENGTH));
}
/**
* The method starts new cluster with defined Configuration; creates a file
* with specified block_size and writes 10 equal sections in it; it also calls
* hflush/hsync after each write and throws an IOException in case of an error.
*
* @param conf cluster configuration
* @param fileName of the file to be created and processed as required
* @param block_size value to be used for the file's creation
* @param replicas is the number of replicas
* @param isSync hsync or hflush
* @param syncFlags specify the semantic of the sync/flush
* @throws IOException in case of any errors
*/
public static void doTheJob(Configuration conf, final String fileName,
long block_size, short replicas) throws IOException {
long block_size, short replicas, boolean isSync,
EnumSet<SyncFlag> syncFlags) throws IOException {
byte[] fileContent;
final int SECTIONS = 10;
@ -119,8 +213,21 @@ public class TestHFlush {
System.out.println("Writing " + (tenth * i) + " to " + (tenth * (i+1)) + " section to file " + fileName);
// write to the file
stm.write(fileContent, tenth * i, tenth);
// Wait while hflush() pushes all packets through built pipeline
// Wait while hflush/hsync pushes all packets through built pipeline
if (isSync) {
((DFSOutputStream)stm.getWrappedStream()).hsync(syncFlags);
} else {
((DFSOutputStream)stm.getWrappedStream()).hflush();
}
// Check file length if updatelength is required
if (isSync && syncFlags.contains(SyncFlag.UPDATE_LENGTH)) {
long currentFileLength = fileSystem.getFileStatus(path).getLen();
assertEquals(
"File size doesn't match for hsync/hflush with updating the length",
tenth * (i + 1), currentFileLength);
}
byte [] toRead = new byte[tenth];
byte [] expected = new byte[tenth];
System.arraycopy(fileContent, tenth * i, expected, 0, tenth);
@ -139,8 +246,6 @@ public class TestHFlush {
assertEquals("File size doesn't match ", AppendTestUtil.FILE_SIZE, fileSystem.getFileStatus(path).getLen());
AppendTestUtil.checkFullFile(fileSystem, path, fileContent.length, fileContent, "hflush()");
} catch (Exception e) {
e.printStackTrace();
} finally {
fileSystem.close();
cluster.shutdown();