/**
* 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 java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InterruptedIOException;
import java.nio.channels.ClosedChannelException;
import java.util.EnumSet;
import java.util.concurrent.atomic.AtomicReference;
import org.apache.hadoop.HadoopIllegalArgumentException;
import org.apache.hadoop.classification.InterfaceAudience;
import org.apache.hadoop.crypto.CryptoProtocolVersion;
import org.apache.hadoop.fs.CanSetDropBehind;
import org.apache.hadoop.fs.CreateFlag;
import org.apache.hadoop.fs.FSOutputSummer;
import org.apache.hadoop.fs.FileAlreadyExistsException;
import org.apache.hadoop.fs.FileEncryptionInfo;
import org.apache.hadoop.fs.ParentNotDirectoryException;
import org.apache.hadoop.fs.Syncable;
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.client.impl.DfsClientConf;
import org.apache.hadoop.hdfs.protocol.DSQuotaExceededException;
import org.apache.hadoop.hdfs.protocol.DatanodeInfo;
import org.apache.hadoop.hdfs.protocol.ExtendedBlock;
import org.apache.hadoop.hdfs.protocol.HdfsFileStatus;
import org.apache.hadoop.hdfs.protocol.LocatedBlock;
import org.apache.hadoop.hdfs.protocol.NSQuotaExceededException;
import org.apache.hadoop.hdfs.protocol.QuotaByStorageTypeExceededException;
import org.apache.hadoop.hdfs.protocol.SnapshotAccessControlException;
import org.apache.hadoop.hdfs.protocol.UnresolvedPathException;
import org.apache.hadoop.hdfs.protocol.datatransfer.PacketHeader;
import org.apache.hadoop.hdfs.security.token.block.BlockTokenIdentifier;
import org.apache.hadoop.hdfs.server.datanode.CachingStrategy;
import org.apache.hadoop.hdfs.server.namenode.RetryStartFileException;
import org.apache.hadoop.hdfs.server.namenode.SafeModeException;
import org.apache.hadoop.hdfs.util.ByteArrayManager;
import org.apache.hadoop.io.EnumSetWritable;
import org.apache.hadoop.ipc.RemoteException;
import org.apache.hadoop.security.AccessControlException;
import org.apache.hadoop.security.token.Token;
import org.apache.hadoop.util.DataChecksum;
import org.apache.hadoop.util.DataChecksum.Type;
import org.apache.hadoop.util.Progressable;
import org.apache.hadoop.util.Time;
import org.apache.htrace.Sampler;
import org.apache.htrace.Trace;
import org.apache.htrace.TraceScope;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import com.google.common.annotations.VisibleForTesting;
import com.google.common.base.Preconditions;
/****************************************************************
* DFSOutputStream creates files from a stream of bytes.
*
* The client application writes data that is cached internally by
* this stream. Data is broken up into packets, each packet is
* typically 64K in size. A packet comprises of chunks. Each chunk
* is typically 512 bytes and has an associated checksum with it.
*
* When a client application fills up the currentPacket, it is
* enqueued into the dataQueue of DataStreamer. DataStreamer is a
* thread that picks up packets from the dataQueue and sends it to
* the first datanode in the pipeline.
*
****************************************************************/
@InterfaceAudience.Private
public class DFSOutputStream extends FSOutputSummer
implements Syncable, CanSetDropBehind {
static final Logger LOG = LoggerFactory.getLogger(DFSOutputStream.class);
/**
* Number of times to retry creating a file when there are transient
* errors (typically related to encryption zones and KeyProvider operations).
*/
@VisibleForTesting
static final int CREATE_RETRY_COUNT = 10;
@VisibleForTesting
static CryptoProtocolVersion[] SUPPORTED_CRYPTO_VERSIONS =
CryptoProtocolVersion.supported();
protected final DFSClient dfsClient;
protected final ByteArrayManager byteArrayManager;
// closed is accessed by different threads under different locks.
protected volatile boolean closed = false;
protected final String src;
protected final long fileId;
protected final long blockSize;
protected final int bytesPerChecksum;
protected DFSPacket currentPacket = null;
private DataStreamer streamer;
protected int packetSize = 0; // write packet size, not including the header.
protected int chunksPerPacket = 0;
protected long lastFlushOffset = 0; // offset when flush was invoked
private long initialFileSize = 0; // at time of file open
private final short blockReplication; // replication factor of file
protected boolean shouldSyncBlock = false; // force blocks to disk upon close
protected final AtomicReference<CachingStrategy> cachingStrategy;
private FileEncryptionInfo fileEncryptionInfo;
/** Use {@link ByteArrayManager} to create buffer for non-heartbeat packets.*/
protected DFSPacket createPacket(int packetSize, int chunksPerPkt, long offsetInBlock,
long seqno, boolean lastPacketInBlock) throws InterruptedIOException {
final byte[] buf;
final int bufferSize = PacketHeader.PKT_MAX_HEADER_LEN + packetSize;
try {
buf = byteArrayManager.newByteArray(bufferSize);
} catch (InterruptedException ie) {
final InterruptedIOException iioe = new InterruptedIOException(
"seqno=" + seqno);
iioe.initCause(ie);
throw iioe;
}
return new DFSPacket(buf, chunksPerPkt, offsetInBlock, seqno,
getChecksumSize(), lastPacketInBlock);
}
@Override
protected void checkClosed() throws IOException {
if (isClosed()) {
getStreamer().getLastException().throwException4Close();
}
}
//
// returns the list of targets, if any, that is being currently used.
//
@VisibleForTesting
public synchronized DatanodeInfo[] getPipeline() {
if (getStreamer().streamerClosed()) {
return null;
}
DatanodeInfo[] currentNodes = getStreamer().getNodes();
if (currentNodes == null) {
return null;
}
DatanodeInfo[] value = new DatanodeInfo[currentNodes.length];
for (int i = 0; i < currentNodes.length; i++) {
value[i] = currentNodes[i];
}
return value;
}
/**
* @return the object for computing checksum.
* The type is NULL if checksum is not computed.
*/
private static DataChecksum getChecksum4Compute(DataChecksum checksum,
HdfsFileStatus stat) {
if (DataStreamer.isLazyPersist(stat) && stat.getReplication() == 1) {
// do not compute checksum for writing to single replica to memory
return DataChecksum.newDataChecksum(Type.NULL,
checksum.getBytesPerChecksum());
}
return checksum;
}
private DFSOutputStream(DFSClient dfsClient, String src, Progressable progress,
HdfsFileStatus stat, DataChecksum checksum) throws IOException {
super(getChecksum4Compute(checksum, stat));
this.dfsClient = dfsClient;
this.src = src;
this.fileId = stat.getFileId();
this.blockSize = stat.getBlockSize();
this.blockReplication = stat.getReplication();
this.fileEncryptionInfo = stat.getFileEncryptionInfo();
this.cachingStrategy = new AtomicReference<CachingStrategy>(
dfsClient.getDefaultWriteCachingStrategy());
if ((progress != null) && DFSClient.LOG.isDebugEnabled()) {
DFSClient.LOG.debug(
"Set non-null progress callback on DFSOutputStream " + src);
}
this.bytesPerChecksum = checksum.getBytesPerChecksum();
if (bytesPerChecksum <= 0) {
throw new HadoopIllegalArgumentException(
"Invalid value: bytesPerChecksum = " + bytesPerChecksum + " <= 0");
}
if (blockSize % bytesPerChecksum != 0) {
throw new HadoopIllegalArgumentException("Invalid values: "
+ DFSConfigKeys.DFS_BYTES_PER_CHECKSUM_KEY + " (=" + bytesPerChecksum
+ ") must divide block size (=" + blockSize + ").");
}
this.byteArrayManager = dfsClient.getClientContext().getByteArrayManager();
}
/** Construct a new output stream for creating a file. */
protected DFSOutputStream(DFSClient dfsClient, String src, HdfsFileStatus stat,
EnumSet<CreateFlag> flag, Progressable progress,
DataChecksum checksum, String[] favoredNodes) throws IOException {
this(dfsClient, src, progress, stat, checksum);
this.shouldSyncBlock = flag.contains(CreateFlag.SYNC_BLOCK);
computePacketChunkSize(dfsClient.getConf().getWritePacketSize(), bytesPerChecksum);
streamer = new DataStreamer(stat, null, dfsClient, src, progress, checksum,
cachingStrategy, byteArrayManager, favoredNodes);
}
static DFSOutputStream newStreamForCreate(DFSClient dfsClient, String src,
FsPermission masked, EnumSet<CreateFlag> flag, boolean createParent,
short replication, long blockSize, Progressable progress, int buffersize,
DataChecksum checksum, String[] favoredNodes) throws IOException {
TraceScope scope =
dfsClient.getPathTraceScope("newStreamForCreate", src);
try {
HdfsFileStatus stat = null;
// Retry the create if we get a RetryStartFileException up to a maximum
// number of times
boolean shouldRetry = true;
int retryCount = CREATE_RETRY_COUNT;
while (shouldRetry) {
shouldRetry = false;
try {
stat = dfsClient.namenode.create(src, masked, dfsClient.clientName,
new EnumSetWritable<CreateFlag>(flag), createParent, replication,
blockSize, SUPPORTED_CRYPTO_VERSIONS);
break;
} catch (RemoteException re) {
IOException e = re.unwrapRemoteException(
AccessControlException.class,
DSQuotaExceededException.class,
QuotaByStorageTypeExceededException.class,
FileAlreadyExistsException.class,
FileNotFoundException.class,
ParentNotDirectoryException.class,
NSQuotaExceededException.class,
RetryStartFileException.class,
SafeModeException.class,
UnresolvedPathException.class,
SnapshotAccessControlException.class,
UnknownCryptoProtocolVersionException.class);
if (e instanceof RetryStartFileException) {
if (retryCount > 0) {
shouldRetry = true;
retryCount--;
} else {
throw new IOException("Too many retries because of encryption" +
" zone operations", e);
}
} else {
throw e;
}
}
}
Preconditions.checkNotNull(stat, "HdfsFileStatus should not be null!");
final DFSOutputStream out = new DFSOutputStream(dfsClient, src, stat,
flag, progress, checksum, favoredNodes);
out.start();
return out;
} finally {
scope.close();
}
}
/** Construct a new output stream for append. */
private DFSOutputStream(DFSClient dfsClient, String src,
EnumSet<CreateFlag> flags, Progressable progress, LocatedBlock lastBlock,
HdfsFileStatus stat, DataChecksum checksum, String[] favoredNodes)
throws IOException {
this(dfsClient, src, progress, stat, checksum);
initialFileSize = stat.getLen(); // length of file when opened
this.shouldSyncBlock = flags.contains(CreateFlag.SYNC_BLOCK);
boolean toNewBlock = flags.contains(CreateFlag.NEW_BLOCK);
this.fileEncryptionInfo = stat.getFileEncryptionInfo();
// The last partial block of the file has to be filled.
if (!toNewBlock && lastBlock != null) {
// indicate that we are appending to an existing block
streamer = new DataStreamer(lastBlock, stat, dfsClient, src, progress, checksum,
cachingStrategy, byteArrayManager);
getStreamer().setBytesCurBlock(lastBlock.getBlockSize());
adjustPacketChunkSize(stat);
getStreamer().setPipelineInConstruction(lastBlock);
} else {
computePacketChunkSize(dfsClient.getConf().getWritePacketSize(),
bytesPerChecksum);
streamer = new DataStreamer(stat, lastBlock != null ? lastBlock.getBlock() : null,
dfsClient, src, progress, checksum, cachingStrategy, byteArrayManager,
favoredNodes);
}
}
private void adjustPacketChunkSize(HdfsFileStatus stat) throws IOException{
long usedInLastBlock = stat.getLen() % blockSize;
int freeInLastBlock = (int)(blockSize - usedInLastBlock);
// calculate the amount of free space in the pre-existing
// last crc chunk
int usedInCksum = (int)(stat.getLen() % bytesPerChecksum);
int freeInCksum = bytesPerChecksum - usedInCksum;
// if there is space in the last block, then we have to
// append to that block
if (freeInLastBlock == blockSize) {
throw new IOException("The last block for file " +
src + " is full.");
}
if (usedInCksum > 0 && freeInCksum > 0) {
// if there is space in the last partial chunk, then
// setup in such a way that the next packet will have only
// one chunk that fills up the partial chunk.
//
computePacketChunkSize(0, freeInCksum);
setChecksumBufSize(freeInCksum);
getStreamer().setAppendChunk(true);
} else {
// if the remaining space in the block is smaller than
// that expected size of of a packet, then create
// smaller size packet.
//
computePacketChunkSize(
Math.min(dfsClient.getConf().getWritePacketSize(), freeInLastBlock),
bytesPerChecksum);
}
}
static DFSOutputStream newStreamForAppend(DFSClient dfsClient, String src,
EnumSet<CreateFlag> flags, int bufferSize, Progressable progress,
LocatedBlock lastBlock, HdfsFileStatus stat, DataChecksum checksum,
String[] favoredNodes) throws IOException {
TraceScope scope =
dfsClient.getPathTraceScope("newStreamForAppend", src);
try {
final DFSOutputStream out = new DFSOutputStream(dfsClient, src, flags,
progress, lastBlock, stat, checksum, favoredNodes);
out.start();
return out;
} finally {
scope.close();
}
}
protected void computePacketChunkSize(int psize, int csize) {
final int bodySize = psize - PacketHeader.PKT_MAX_HEADER_LEN;
final int chunkSize = csize + getChecksumSize();
chunksPerPacket = Math.max(bodySize/chunkSize, 1);
packetSize = chunkSize*chunksPerPacket;
if (DFSClient.LOG.isDebugEnabled()) {
DFSClient.LOG.debug("computePacketChunkSize: src=" + src +
", chunkSize=" + chunkSize +
", chunksPerPacket=" + chunksPerPacket +
", packetSize=" + packetSize);
}
}
protected TraceScope createWriteTraceScope() {
return dfsClient.getPathTraceScope("DFSOutputStream#write", src);
}
// @see FSOutputSummer#writeChunk()
@Override
protected synchronized void writeChunk(byte[] b, int offset, int len,
byte[] checksum, int ckoff, int cklen) throws IOException {
dfsClient.checkOpen();
checkClosed();
if (len > bytesPerChecksum) {
throw new IOException("writeChunk() buffer size is " + len +
" is larger than supported bytesPerChecksum " +
bytesPerChecksum);
}
if (cklen != 0 && cklen != getChecksumSize()) {
throw new IOException("writeChunk() checksum size is supposed to be " +
getChecksumSize() + " but found to be " + cklen);
}
if (currentPacket == null) {
currentPacket = createPacket(packetSize, chunksPerPacket, getStreamer()
.getBytesCurBlock(), getStreamer().getAndIncCurrentSeqno(), false);
if (DFSClient.LOG.isDebugEnabled()) {
DFSClient.LOG.debug("DFSClient writeChunk allocating new packet seqno=" +
currentPacket.getSeqno() +
", src=" + src +
", packetSize=" + packetSize +
", chunksPerPacket=" + chunksPerPacket +
", bytesCurBlock=" + getStreamer().getBytesCurBlock());
}
}
currentPacket.writeChecksum(checksum, ckoff, cklen);
currentPacket.writeData(b, offset, len);
currentPacket.incNumChunks();
getStreamer().incBytesCurBlock(len);
// If packet is full, enqueue it for transmission
//
if (currentPacket.getNumChunks() == currentPacket.getMaxChunks() ||
getStreamer().getBytesCurBlock() == blockSize) {
enqueueCurrentPacketFull();
}
}
void enqueueCurrentPacket() throws IOException {
getStreamer().waitAndQueuePacket(currentPacket);
currentPacket = null;
}
void enqueueCurrentPacketFull() throws IOException {
LOG.debug("enqueue full {}, src={}, bytesCurBlock={}, blockSize={},"
+ " appendChunk={}, {}", currentPacket, src, getStreamer()
.getBytesCurBlock(), blockSize, getStreamer().getAppendChunk(),
getStreamer());
enqueueCurrentPacket();
adjustChunkBoundary();
endBlock();
}
/** create an empty packet to mark the end of the block. */
void setCurrentPacketToEmpty() throws InterruptedIOException {
currentPacket = createPacket(0, 0, getStreamer().getBytesCurBlock(),
getStreamer().getAndIncCurrentSeqno(), true);
currentPacket.setSyncBlock(shouldSyncBlock);
}
/**
* If the reopened file did not end at chunk boundary and the above
* write filled up its partial chunk. Tell the summer to generate full
* crc chunks from now on.
*/
protected void adjustChunkBoundary() {
if (getStreamer().getAppendChunk() &&
getStreamer().getBytesCurBlock() % bytesPerChecksum == 0) {
getStreamer().setAppendChunk(false);
resetChecksumBufSize();
}
if (!getStreamer().getAppendChunk()) {
int psize = Math.min((int)(blockSize- getStreamer().getBytesCurBlock()),
dfsClient.getConf().getWritePacketSize());
computePacketChunkSize(psize, bytesPerChecksum);
}
}
/**
* if encountering a block boundary, send an empty packet to
* indicate the end of block and reset bytesCurBlock.
*
* @throws IOException
*/
protected void endBlock() throws IOException {
if (getStreamer().getBytesCurBlock() == blockSize) {
setCurrentPacketToEmpty();
enqueueCurrentPacket();
getStreamer().setBytesCurBlock(0);
lastFlushOffset = 0;
}
}
@Deprecated
public void sync() throws IOException {
hflush();
}
/**
* Flushes out to all replicas of the block. The data is in the buffers
* of the DNs but not necessarily in the DN's OS buffers.
*
* It is a synchronous operation. When it returns,
* it guarantees that flushed data become visible to new readers.
* It is not guaranteed that data has been flushed to
* persistent store on the datanode.
* Block allocations are persisted on namenode.
*/
@Override
public void hflush() throws IOException {
TraceScope scope =
dfsClient.getPathTraceScope("hflush", src);
try {
flushOrSync(false, EnumSet.noneOf(SyncFlag.class));
} finally {
scope.close();
}
}
@Override
public void hsync() throws IOException {
TraceScope scope =
dfsClient.getPathTraceScope("hsync", src);
try {
flushOrSync(true, EnumSet.noneOf(SyncFlag.class));
} finally {
scope.close();
}
}
/**
* The expected semantics is all data have flushed out to all replicas
* and all replicas have done posix fsync equivalent - ie the OS has
* flushed it to the disk device (but the disk may have it in its cache).
*
* 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.
*/
public void hsync(EnumSet<SyncFlag> syncFlags) throws IOException {
TraceScope scope =
dfsClient.getPathTraceScope("hsync", src);
try {
flushOrSync(true, syncFlags);
} finally {
scope.close();
}
}
/**
* 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();
checkClosed();
try {
long toWaitFor;
long lastBlockLength = -1L;
boolean updateLength = syncFlags.contains(SyncFlag.UPDATE_LENGTH);
boolean endBlock = syncFlags.contains(SyncFlag.END_BLOCK);
synchronized (this) {
// flush checksum buffer, but keep checksum buffer intact if we do not
// need to end the current block
int numKept = flushBuffer(!endBlock, true);
// bytesCurBlock potentially incremented if there was buffered data
if (DFSClient.LOG.isDebugEnabled()) {
DFSClient.LOG.debug("DFSClient flush(): "
+ " bytesCurBlock=" + getStreamer().getBytesCurBlock()
+ " lastFlushOffset=" + lastFlushOffset
+ " createNewBlock=" + endBlock);
}
// Flush only if we haven't already flushed till this offset.
if (lastFlushOffset != getStreamer().getBytesCurBlock()) {
assert getStreamer().getBytesCurBlock() > lastFlushOffset;
// record the valid offset of this flush
lastFlushOffset = getStreamer().getBytesCurBlock();
if (isSync && currentPacket == null && !endBlock) {
// Nothing to send right now,
// but sync was requested.
// Send an empty packet if we do not end the block right now
currentPacket = createPacket(packetSize, chunksPerPacket,
getStreamer().getBytesCurBlock(), getStreamer()
.getAndIncCurrentSeqno(), false);
}
} else {
if (isSync && getStreamer().getBytesCurBlock() > 0 && !endBlock) {
// Nothing to send right now,
// and the block was partially written,
// and sync was requested.
// So send an empty sync packet if we do not end the block right
// now
currentPacket = createPacket(packetSize, chunksPerPacket,
getStreamer().getBytesCurBlock(), getStreamer()
.getAndIncCurrentSeqno(), false);
} else if (currentPacket != null) {
// just discard the current packet since it is already been sent.
currentPacket.releaseBuffer(byteArrayManager);
currentPacket = null;
}
}
if (currentPacket != null) {
currentPacket.setSyncBlock(isSync);
enqueueCurrentPacket();
}
if (endBlock && getStreamer().getBytesCurBlock() > 0) {
// Need to end the current block, thus send an empty packet to
// indicate this is the end of the block and reset bytesCurBlock
currentPacket = createPacket(0, 0, getStreamer().getBytesCurBlock(),
getStreamer().getAndIncCurrentSeqno(), true);
currentPacket.setSyncBlock(shouldSyncBlock || isSync);
enqueueCurrentPacket();
getStreamer().setBytesCurBlock(0);
lastFlushOffset = 0;
} else {
// Restore state of stream. Record the last flush offset
// of the last full chunk that was flushed.
getStreamer().setBytesCurBlock(
getStreamer().getBytesCurBlock() - numKept);
}
toWaitFor = getStreamer().getLastQueuedSeqno();
} // end synchronized
getStreamer().waitForAckedSeqno(toWaitFor);
// update the block length first time irrespective of flag
if (updateLength || getStreamer().getPersistBlocks().get()) {
synchronized (this) {
if (!getStreamer().streamerClosed()
&& getStreamer().getBlock() != null) {
lastBlockLength = getStreamer().getBlock().getNumBytes();
}
}
}
// If 1) any new blocks were allocated since the last flush, or 2) to
// update length in NN is required, then persist block locations on
// namenode.
if (getStreamer().getPersistBlocks().getAndSet(false) || updateLength) {
try {
dfsClient.namenode.fsync(src, fileId, 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
// close before our hflush completed. In that case, we should throw an
// exception that the stream is closed.
checkClosed();
// If we aren't closed but failed to sync, we should expose that to the
// caller.
throw ioe;
}
}
synchronized(this) {
if (!getStreamer().streamerClosed()) {
getStreamer().setHflush();
}
}
} catch (InterruptedIOException interrupt) {
// This kind of error doesn't mean that the stream itself is broken - just the
// flushing thread got interrupted. So, we shouldn't close down the writer,
// but instead just propagate the error
throw interrupt;
} catch (IOException e) {
DFSClient.LOG.warn("Error while syncing", e);
synchronized (this) {
if (!isClosed()) {
getStreamer().getLastException().set(e);
closeThreads(true);
}
}
throw e;
}
}
/**
* @deprecated use {@link HdfsDataOutputStream#getCurrentBlockReplication()}.
*/
@Deprecated
public synchronized int getNumCurrentReplicas() throws IOException {
return getCurrentBlockReplication();
}
/**
* Note that this is not a public API;
* use {@link HdfsDataOutputStream#getCurrentBlockReplication()} instead.
*
* @return the number of valid replicas of the current block
*/
public synchronized int getCurrentBlockReplication() throws IOException {
dfsClient.checkOpen();
checkClosed();
if (getStreamer().streamerClosed()) {
return blockReplication; // no pipeline, return repl factor of file
}
DatanodeInfo[] currentNodes = getStreamer().getNodes();
if (currentNodes == null) {
return blockReplication; // no pipeline, return repl factor of file
}
return currentNodes.length;
}
/**
* Waits till all existing data is flushed and confirmations
* received from datanodes.
*/
protected void flushInternal() throws IOException {
long toWaitFor;
synchronized (this) {
dfsClient.checkOpen();
checkClosed();
//
// If there is data in the current buffer, send it across
//
getStreamer().queuePacket(currentPacket);
currentPacket = null;
toWaitFor = getStreamer().getLastQueuedSeqno();
}
getStreamer().waitForAckedSeqno(toWaitFor);
}
protected synchronized void start() {
getStreamer().start();
}
/**
* Aborts this output stream and releases any system
* resources associated with this stream.
*/
synchronized void abort() throws IOException {
if (isClosed()) {
return;
}
getStreamer().getLastException().set(new IOException("Lease timeout of "
+ (dfsClient.getConf().getHdfsTimeout()/1000) + " seconds expired."));
closeThreads(true);
dfsClient.endFileLease(fileId);
}
boolean isClosed() {
return closed || getStreamer().streamerClosed();
}
void setClosed() {
closed = true;
getStreamer().release();
}
// shutdown datastreamer and responseprocessor threads.
// interrupt datastreamer if force is true
protected void closeThreads(boolean force) throws IOException {
try {
getStreamer().close(force);
getStreamer().join();
getStreamer().closeSocket();
} catch (InterruptedException e) {
throw new IOException("Failed to shutdown streamer");
} finally {
getStreamer().setSocketToNull();
setClosed();
}
}
/**
* Closes this output stream and releases any system
* resources associated with this stream.
*/
@Override
public synchronized void close() throws IOException {
TraceScope scope =
dfsClient.getPathTraceScope("DFSOutputStream#close", src);
try {
closeImpl();
} finally {
scope.close();
}
}
protected synchronized void closeImpl() throws IOException {
if (isClosed()) {
getStreamer().getLastException().check(true);
return;
}
try {
flushBuffer(); // flush from all upper layers
if (currentPacket != null) {
enqueueCurrentPacket();
}
if (getStreamer().getBytesCurBlock() != 0) {
setCurrentPacketToEmpty();
}
flushInternal(); // flush all data to Datanodes
// get last block before destroying the streamer
ExtendedBlock lastBlock = getStreamer().getBlock();
closeThreads(false);
TraceScope scope = Trace.startSpan("completeFile", Sampler.NEVER);
try {
completeFile(lastBlock);
} finally {
scope.close();
}
dfsClient.endFileLease(fileId);
} catch (ClosedChannelException e) {
} finally {
setClosed();
}
}
// should be called holding (this) lock since setTestFilename() may
// be called during unit tests
protected void completeFile(ExtendedBlock last) throws IOException {
long localstart = Time.monotonicNow();
final DfsClientConf conf = dfsClient.getConf();
long sleeptime = conf.getBlockWriteLocateFollowingInitialDelayMs();
boolean fileComplete = false;
int retries = conf.getNumBlockWriteLocateFollowingRetry();
while (!fileComplete) {
fileComplete =
dfsClient.namenode.complete(src, dfsClient.clientName, last, fileId);
if (!fileComplete) {
final int hdfsTimeout = conf.getHdfsTimeout();
if (!dfsClient.clientRunning
|| (hdfsTimeout > 0
&& localstart + hdfsTimeout < Time.monotonicNow())) {
String msg = "Unable to close file because dfsclient " +
" was unable to contact the HDFS servers." +
" clientRunning " + dfsClient.clientRunning +
" hdfsTimeout " + hdfsTimeout;
DFSClient.LOG.info(msg);
throw new IOException(msg);
}
try {
if (retries == 0) {
throw new IOException("Unable to close file because the last block"
+ " does not have enough number of replicas.");
}
retries--;
Thread.sleep(sleeptime);
sleeptime *= 2;
if (Time.monotonicNow() - localstart > 5000) {
DFSClient.LOG.info("Could not complete " + src + " retrying...");
}
} catch (InterruptedException ie) {
DFSClient.LOG.warn("Caught exception ", ie);
}
}
}
}
@VisibleForTesting
public void setArtificialSlowdown(long period) {
getStreamer().setArtificialSlowdown(period);
}
@VisibleForTesting
public synchronized void setChunksPerPacket(int value) {
chunksPerPacket = Math.min(chunksPerPacket, value);
packetSize = (bytesPerChecksum + getChecksumSize()) * chunksPerPacket;
}
/**
* Returns the size of a file as it was when this stream was opened
*/
public long getInitialLen() {
return initialFileSize;
}
/**
* @return the FileEncryptionInfo for this stream, or null if not encrypted.
*/
public FileEncryptionInfo getFileEncryptionInfo() {
return fileEncryptionInfo;
}
/**
* Returns the access token currently used by streamer, for testing only
*/
synchronized Token<BlockTokenIdentifier> getBlockToken() {
return getStreamer().getBlockToken();
}
@Override
public void setDropBehind(Boolean dropBehind) throws IOException {
CachingStrategy prevStrategy, nextStrategy;
// CachingStrategy is immutable. So build a new CachingStrategy with the
// modifications we want, and compare-and-swap it in.
do {
prevStrategy = this.cachingStrategy.get();
nextStrategy = new CachingStrategy.Builder(prevStrategy).
setDropBehind(dropBehind).build();
} while (!this.cachingStrategy.compareAndSet(prevStrategy, nextStrategy));
}
@VisibleForTesting
ExtendedBlock getBlock() {
return getStreamer().getBlock();
}
@VisibleForTesting
public long getFileId() {
return fileId;
}
/**
* Returns the data streamer object.
*/
protected DataStreamer getStreamer() {
return streamer;
}
}