/**
* 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.apache.hadoop.hdfs.protocol.proto.DataTransferProtos.Status.SUCCESS;
import java.io.BufferedOutputStream;
import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.io.InterruptedIOException;
import java.io.OutputStream;
import java.net.InetSocketAddress;
import java.net.Socket;
import java.nio.BufferOverflowException;
import java.nio.channels.ClosedChannelException;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.EnumSet;
import java.util.LinkedList;
import java.util.List;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.atomic.AtomicBoolean;
import java.util.concurrent.atomic.AtomicReference;
import org.apache.hadoop.classification.InterfaceAudience;
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.ParentNotDirectoryException;
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;
import org.apache.hadoop.hdfs.protocol.HdfsConstants;
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.SnapshotAccessControlException;
import org.apache.hadoop.hdfs.protocol.UnresolvedPathException;
import org.apache.hadoop.hdfs.protocol.datatransfer.BlockConstructionStage;
import org.apache.hadoop.hdfs.protocol.datatransfer.DataTransferProtocol;
import org.apache.hadoop.hdfs.protocol.datatransfer.DataTransferEncryptor;
import org.apache.hadoop.hdfs.protocol.datatransfer.IOStreamPair;
import org.apache.hadoop.hdfs.protocol.datatransfer.InvalidEncryptionKeyException;
import org.apache.hadoop.hdfs.protocol.datatransfer.PacketHeader;
import org.apache.hadoop.hdfs.protocol.datatransfer.PipelineAck;
import org.apache.hadoop.hdfs.protocol.datatransfer.Sender;
import org.apache.hadoop.hdfs.protocol.proto.DataTransferProtos.BlockOpResponseProto;
import org.apache.hadoop.hdfs.protocol.proto.DataTransferProtos.Status;
import org.apache.hadoop.hdfs.protocolPB.PBHelper;
import org.apache.hadoop.hdfs.security.token.block.BlockTokenIdentifier;
import org.apache.hadoop.hdfs.security.token.block.InvalidBlockTokenException;
import org.apache.hadoop.hdfs.server.datanode.CachingStrategy;
import org.apache.hadoop.hdfs.server.namenode.NotReplicatedYetException;
import org.apache.hadoop.hdfs.server.namenode.SafeModeException;
import org.apache.hadoop.io.EnumSetWritable;
import org.apache.hadoop.io.IOUtils;
import org.apache.hadoop.ipc.RemoteException;
import org.apache.hadoop.net.NetUtils;
import org.apache.hadoop.security.AccessControlException;
import org.apache.hadoop.security.token.Token;
import org.apache.hadoop.util.Daemon;
import org.apache.hadoop.util.DataChecksum;
import org.apache.hadoop.util.Progressable;
import org.apache.hadoop.util.Time;
import com.google.common.annotations.VisibleForTesting;
import com.google.common.cache.CacheBuilder;
import com.google.common.cache.CacheLoader;
import com.google.common.cache.LoadingCache;
import com.google.common.cache.RemovalListener;
import com.google.common.cache.RemovalNotification;
/****************************************************************
* 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 dataQueue. The DataStreamer thread picks up
* packets from the dataQueue, sends it to the first datanode in
* the pipeline and moves it from the dataQueue to the ackQueue.
* The ResponseProcessor receives acks from the datanodes. When an
* successful ack for a packet is received from all datanodes, the
* ResponseProcessor removes the corresponding packet from the
* ackQueue.
*
* In case of error, all outstanding packets and moved from
* ackQueue. A new pipeline is setup by eliminating the bad
* datanode from the original pipeline. The DataStreamer now
* starts sending packets from the dataQueue.
****************************************************************/
@InterfaceAudience.Private
public class DFSOutputStream extends FSOutputSummer
implements Syncable, CanSetDropBehind {
private final DFSClient dfsClient;
private static final int MAX_PACKETS = 80; // each packet 64K, total 5MB
private Socket s;
// closed is accessed by different threads under different locks.
private volatile boolean closed = false;
private String src;
private final long fileId;
private final long blockSize;
private final DataChecksum checksum;
// both dataQueue and ackQueue are protected by dataQueue lock
private final LinkedList<Packet> dataQueue = new LinkedList<Packet>();
private final LinkedList<Packet> ackQueue = new LinkedList<Packet>();
private Packet currentPacket = null;
private DataStreamer streamer;
private long currentSeqno = 0;
private long lastQueuedSeqno = -1;
private long lastAckedSeqno = -1;
private long bytesCurBlock = 0; // bytes writen in current block
private int packetSize = 0; // write packet size, not including the header.
private int chunksPerPacket = 0;
private final AtomicReference<IOException> lastException = new AtomicReference<IOException>();
private long artificialSlowdown = 0;
private long lastFlushOffset = 0; // offset when flush was invoked
//persist blocks on namenode
private final AtomicBoolean persistBlocks = new AtomicBoolean(false);
private volatile boolean appendChunk = false; // appending to existing partial block
private long initialFileSize = 0; // at time of file open
private Progressable progress;
private final short blockReplication; // replication factor of file
private boolean shouldSyncBlock = false; // force blocks to disk upon close
private CachingStrategy cachingStrategy;
private class Packet {
long seqno; // sequencenumber of buffer in block
long offsetInBlock; // offset in block
private boolean lastPacketInBlock; // is this the last packet in block?
boolean syncBlock; // this packet forces the current block to disk
int numChunks; // number of chunks currently in packet
int maxChunks; // max chunks in packet
byte[] buf;
/**
* buf is pointed into like follows:
* (C is checksum data, D is payload data)
*
* [_________CCCCCCCCC________________DDDDDDDDDDDDDDDD___]
* ^ ^ ^ ^
* | checksumPos dataStart dataPos
* checksumStart
*
* Right before sending, we move the checksum data to immediately precede
* the actual data, and then insert the header into the buffer immediately
* preceding the checksum data, so we make sure to keep enough space in
* front of the checksum data to support the largest conceivable header.
*/
int checksumStart;
int checksumPos;
int dataStart;
int dataPos;
private static final long HEART_BEAT_SEQNO = -1L;
/**
* Create a heartbeat packet.
*/
Packet() {
this.lastPacketInBlock = false;
this.numChunks = 0;
this.offsetInBlock = 0;
this.seqno = HEART_BEAT_SEQNO;
buf = new byte[PacketHeader.PKT_MAX_HEADER_LEN];
checksumStart = checksumPos = dataPos = dataStart = PacketHeader.PKT_MAX_HEADER_LEN;
maxChunks = 0;
}
/**
* Create a new packet.
*
* @param pktSize maximum size of the packet, including checksum data and actual data.
* @param chunksPerPkt maximum number of chunks per packet.
* @param offsetInBlock offset in bytes into the HDFS block.
*/
Packet(int pktSize, int chunksPerPkt, long offsetInBlock) {
this.lastPacketInBlock = false;
this.numChunks = 0;
this.offsetInBlock = offsetInBlock;
this.seqno = currentSeqno;
currentSeqno++;
buf = new byte[PacketHeader.PKT_MAX_HEADER_LEN + pktSize];
checksumStart = PacketHeader.PKT_MAX_HEADER_LEN;
checksumPos = checksumStart;
dataStart = checksumStart + (chunksPerPkt * checksum.getChecksumSize());
dataPos = dataStart;
maxChunks = chunksPerPkt;
}
void writeData(byte[] inarray, int off, int len) {
if (dataPos + len > buf.length) {
throw new BufferOverflowException();
}
System.arraycopy(inarray, off, buf, dataPos, len);
dataPos += len;
}
void writeChecksum(byte[] inarray, int off, int len) {
if (checksumPos + len > dataStart) {
throw new BufferOverflowException();
}
System.arraycopy(inarray, off, buf, checksumPos, len);
checksumPos += len;
}
/**
* Write the full packet, including the header, to the given output stream.
*/
void writeTo(DataOutputStream stm) throws IOException {
final int dataLen = dataPos - dataStart;
final int checksumLen = checksumPos - checksumStart;
final int pktLen = HdfsConstants.BYTES_IN_INTEGER + dataLen + checksumLen;
PacketHeader header = new PacketHeader(
pktLen, offsetInBlock, seqno, lastPacketInBlock, dataLen, syncBlock);
if (checksumPos != dataStart) {
// Move the checksum to cover the gap. This can happen for the last
// packet or during an hflush/hsync call.
System.arraycopy(buf, checksumStart, buf,
dataStart - checksumLen , checksumLen);
checksumPos = dataStart;
checksumStart = checksumPos - checksumLen;
}
final int headerStart = checksumStart - header.getSerializedSize();
assert checksumStart + 1 >= header.getSerializedSize();
assert checksumPos == dataStart;
assert headerStart >= 0;
assert headerStart + header.getSerializedSize() == checksumStart;
// Copy the header data into the buffer immediately preceding the checksum
// data.
System.arraycopy(header.getBytes(), 0, buf, headerStart,
header.getSerializedSize());
// corrupt the data for testing.
if (DFSClientFaultInjector.get().corruptPacket()) {
buf[headerStart+header.getSerializedSize() + checksumLen + dataLen-1] ^= 0xff;
}
// Write the now contiguous full packet to the output stream.
stm.write(buf, headerStart, header.getSerializedSize() + checksumLen + dataLen);
// undo corruption.
if (DFSClientFaultInjector.get().uncorruptPacket()) {
buf[headerStart+header.getSerializedSize() + checksumLen + dataLen-1] ^= 0xff;
}
}
// get the packet's last byte's offset in the block
long getLastByteOffsetBlock() {
return offsetInBlock + dataPos - dataStart;
}
/**
* Check if this packet is a heart beat packet
* @return true if the sequence number is HEART_BEAT_SEQNO
*/
private boolean isHeartbeatPacket() {
return seqno == HEART_BEAT_SEQNO;
}
@Override
public String toString() {
return "packet seqno:" + this.seqno +
" offsetInBlock:" + this.offsetInBlock +
" lastPacketInBlock:" + this.lastPacketInBlock +
" lastByteOffsetInBlock: " + this.getLastByteOffsetBlock();
}
}
//
// The DataStreamer class is responsible for sending data packets to the
// datanodes in the pipeline. It retrieves a new blockid and block locations
// from the namenode, and starts streaming packets to the pipeline of
// Datanodes. Every packet has a sequence number associated with
// it. When all the packets for a block are sent out and acks for each
// if them are received, the DataStreamer closes the current block.
//
class DataStreamer extends Daemon {
private volatile boolean streamerClosed = false;
private ExtendedBlock block; // its length is number of bytes acked
private Token<BlockTokenIdentifier> accessToken;
private DataOutputStream blockStream;
private DataInputStream blockReplyStream;
private ResponseProcessor response = null;
private volatile DatanodeInfo[] nodes = null; // list of targets for current block
private LoadingCache<DatanodeInfo, DatanodeInfo> excludedNodes =
CacheBuilder.newBuilder()
.expireAfterWrite(
dfsClient.getConf().excludedNodesCacheExpiry,
TimeUnit.MILLISECONDS)
.removalListener(new RemovalListener<DatanodeInfo, DatanodeInfo>() {
@Override
public void onRemoval(
RemovalNotification<DatanodeInfo, DatanodeInfo> notification) {
DFSClient.LOG.info("Removing node " +
notification.getKey() + " from the excluded nodes list");
}
})
.build(new CacheLoader<DatanodeInfo, DatanodeInfo>() {
@Override
public DatanodeInfo load(DatanodeInfo key) throws Exception {
return key;
}
});
private String[] favoredNodes;
volatile boolean hasError = false;
volatile int errorIndex = -1;
private BlockConstructionStage stage; // block construction stage
private long bytesSent = 0; // number of bytes that've been sent
/** Nodes have been used in the pipeline before and have failed. */
private final List<DatanodeInfo> failed = new ArrayList<DatanodeInfo>();
/** The last ack sequence number before pipeline failure. */
private long lastAckedSeqnoBeforeFailure = -1;
private int pipelineRecoveryCount = 0;
/** Has the current block been hflushed? */
private boolean isHflushed = false;
/** Append on an existing block? */
private final boolean isAppend;
/**
* Default construction for file create
*/
private DataStreamer() {
isAppend = false;
stage = BlockConstructionStage.PIPELINE_SETUP_CREATE;
}
/**
* Construct a data streamer for append
* @param lastBlock last block of the file to be appended
* @param stat status of the file to be appended
* @param bytesPerChecksum number of bytes per checksum
* @throws IOException if error occurs
*/
private DataStreamer(LocatedBlock lastBlock, HdfsFileStatus stat,
int bytesPerChecksum) throws IOException {
isAppend = true;
stage = BlockConstructionStage.PIPELINE_SETUP_APPEND;
block = lastBlock.getBlock();
bytesSent = block.getNumBytes();
accessToken = lastBlock.getBlockToken();
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);
resetChecksumChunk(freeInCksum);
appendChunk = 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().writePacketSize, freeInLastBlock),
bytesPerChecksum);
}
// setup pipeline to append to the last block XXX retries??
nodes = lastBlock.getLocations();
errorIndex = -1; // no errors yet.
if (nodes.length < 1) {
throw new IOException("Unable to retrieve blocks locations " +
" for last block " + block +
"of file " + src);
}
}
private void setFavoredNodes(String[] favoredNodes) {
this.favoredNodes = favoredNodes;
}
/**
* Initialize for data streaming
*/
private void initDataStreaming() {
this.setName("DataStreamer for file " + src +
" block " + block);
response = new ResponseProcessor(nodes);
response.start();
stage = BlockConstructionStage.DATA_STREAMING;
}
private void endBlock() {
if(DFSClient.LOG.isDebugEnabled()) {
DFSClient.LOG.debug("Closing old block " + block);
}
this.setName("DataStreamer for file " + src);
closeResponder();
closeStream();
nodes = null;
stage = BlockConstructionStage.PIPELINE_SETUP_CREATE;
}
/*
* streamer thread is the only thread that opens streams to datanode,
* and closes them. Any error recovery is also done by this thread.
*/
@Override
public void run() {
long lastPacket = Time.now();
while (!streamerClosed && dfsClient.clientRunning) {
// if the Responder encountered an error, shutdown Responder
if (hasError && response != null) {
try {
response.close();
response.join();
response = null;
} catch (InterruptedException e) {
}
}
Packet one = null;
try {
// process datanode IO errors if any
boolean doSleep = false;
if (hasError && errorIndex>=0) {
doSleep = processDatanodeError();
}
synchronized (dataQueue) {
// wait for a packet to be sent.
long now = Time.now();
while ((!streamerClosed && !hasError && dfsClient.clientRunning
&& dataQueue.size() == 0 &&
(stage != BlockConstructionStage.DATA_STREAMING ||
stage == BlockConstructionStage.DATA_STREAMING &&
now - lastPacket < dfsClient.getConf().socketTimeout/2)) || doSleep ) {
long timeout = dfsClient.getConf().socketTimeout/2 - (now-lastPacket);
timeout = timeout <= 0 ? 1000 : timeout;
timeout = (stage == BlockConstructionStage.DATA_STREAMING)?
timeout : 1000;
try {
dataQueue.wait(timeout);
} catch (InterruptedException e) {
}
doSleep = false;
now = Time.now();
}
if (streamerClosed || hasError || !dfsClient.clientRunning) {
continue;
}
// get packet to be sent.
if (dataQueue.isEmpty()) {
one = new Packet(); // heartbeat packet
} else {
one = dataQueue.getFirst(); // regular data packet
}
}
assert one != null;
// get new block from namenode.
if (stage == BlockConstructionStage.PIPELINE_SETUP_CREATE) {
if(DFSClient.LOG.isDebugEnabled()) {
DFSClient.LOG.debug("Allocating new block");
}
nodes = nextBlockOutputStream(src);
initDataStreaming();
} else if (stage == BlockConstructionStage.PIPELINE_SETUP_APPEND) {
if(DFSClient.LOG.isDebugEnabled()) {
DFSClient.LOG.debug("Append to block " + block);
}
setupPipelineForAppendOrRecovery();
initDataStreaming();
}
long lastByteOffsetInBlock = one.getLastByteOffsetBlock();
if (lastByteOffsetInBlock > blockSize) {
throw new IOException("BlockSize " + blockSize +
" is smaller than data size. " +
" Offset of packet in block " +
lastByteOffsetInBlock +
" Aborting file " + src);
}
if (one.lastPacketInBlock) {
// wait for all data packets have been successfully acked
synchronized (dataQueue) {
while (!streamerClosed && !hasError &&
ackQueue.size() != 0 && dfsClient.clientRunning) {
try {
// wait for acks to arrive from datanodes
dataQueue.wait(1000);
} catch (InterruptedException e) {
}
}
}
if (streamerClosed || hasError || !dfsClient.clientRunning) {
continue;
}
stage = BlockConstructionStage.PIPELINE_CLOSE;
}
// send the packet
synchronized (dataQueue) {
// move packet from dataQueue to ackQueue
if (!one.isHeartbeatPacket()) {
dataQueue.removeFirst();
ackQueue.addLast(one);
dataQueue.notifyAll();
}
}
if (DFSClient.LOG.isDebugEnabled()) {
DFSClient.LOG.debug("DataStreamer block " + block +
" sending packet " + one);
}
// write out data to remote datanode
try {
one.writeTo(blockStream);
blockStream.flush();
} catch (IOException e) {
// HDFS-3398 treat primary DN is down since client is unable to
// write to primary DN
errorIndex = 0;
throw e;
}
lastPacket = Time.now();
if (one.isHeartbeatPacket()) { //heartbeat packet
}
// update bytesSent
long tmpBytesSent = one.getLastByteOffsetBlock();
if (bytesSent < tmpBytesSent) {
bytesSent = tmpBytesSent;
}
if (streamerClosed || hasError || !dfsClient.clientRunning) {
continue;
}
// Is this block full?
if (one.lastPacketInBlock) {
// wait for the close packet has been acked
synchronized (dataQueue) {
while (!streamerClosed && !hasError &&
ackQueue.size() != 0 && dfsClient.clientRunning) {
dataQueue.wait(1000);// wait for acks to arrive from datanodes
}
}
if (streamerClosed || hasError || !dfsClient.clientRunning) {
continue;
}
endBlock();
}
if (progress != null) { progress.progress(); }
// This is used by unit test to trigger race conditions.
if (artificialSlowdown != 0 && dfsClient.clientRunning) {
Thread.sleep(artificialSlowdown);
}
} catch (Throwable e) {
DFSClient.LOG.warn("DataStreamer Exception", e);
if (e instanceof IOException) {
setLastException((IOException)e);
}
hasError = true;
if (errorIndex == -1) { // not a datanode error
streamerClosed = true;
}
}
}
closeInternal();
}
private void closeInternal() {
closeResponder(); // close and join
closeStream();
streamerClosed = true;
closed = true;
synchronized (dataQueue) {
dataQueue.notifyAll();
}
}
/*
* close both streamer and DFSOutputStream, should be called only
* by an external thread and only after all data to be sent has
* been flushed to datanode.
*
* Interrupt this data streamer if force is true
*
* @param force if this data stream is forced to be closed
*/
void close(boolean force) {
streamerClosed = true;
synchronized (dataQueue) {
dataQueue.notifyAll();
}
if (force) {
this.interrupt();
}
}
private void closeResponder() {
if (response != null) {
try {
response.close();
response.join();
} catch (InterruptedException e) {
} finally {
response = null;
}
}
}
private void closeStream() {
if (blockStream != null) {
try {
blockStream.close();
} catch (IOException e) {
setLastException(e);
} finally {
blockStream = null;
}
}
if (blockReplyStream != null) {
try {
blockReplyStream.close();
} catch (IOException e) {
setLastException(e);
} finally {
blockReplyStream = null;
}
}
if (null != s) {
try {
s.close();
} catch (IOException e) {
setLastException(e);
} finally {
s = null;
}
}
}
//
// Processes reponses from the datanodes. A packet is removed
// from the ackQueue when its response arrives.
//
private class ResponseProcessor extends Daemon {
private volatile boolean responderClosed = false;
private DatanodeInfo[] targets = null;
private boolean isLastPacketInBlock = false;
ResponseProcessor (DatanodeInfo[] targets) {
this.targets = targets;
}
@Override
public void run() {
setName("ResponseProcessor for block " + block);
PipelineAck ack = new PipelineAck();
while (!responderClosed && dfsClient.clientRunning && !isLastPacketInBlock) {
// process responses from datanodes.
try {
// read an ack from the pipeline
ack.readFields(blockReplyStream);
if (DFSClient.LOG.isDebugEnabled()) {
DFSClient.LOG.debug("DFSClient " + ack);
}
long seqno = ack.getSeqno();
// processes response status from datanodes.
for (int i = ack.getNumOfReplies()-1; i >=0 && dfsClient.clientRunning; i--) {
final Status reply = ack.getReply(i);
if (reply != SUCCESS) {
errorIndex = i; // first bad datanode
throw new IOException("Bad response " + reply +
" for block " + block +
" from datanode " +
targets[i]);
}
}
assert seqno != PipelineAck.UNKOWN_SEQNO :
"Ack for unkown seqno should be a failed ack: " + ack;
if (seqno == Packet.HEART_BEAT_SEQNO) { // a heartbeat ack
continue;
}
// a success ack for a data packet
Packet one = null;
synchronized (dataQueue) {
one = ackQueue.getFirst();
}
if (one.seqno != seqno) {
throw new IOException("Responseprocessor: Expecting seqno " +
" for block " + block +
one.seqno + " but received " + seqno);
}
isLastPacketInBlock = one.lastPacketInBlock;
// update bytesAcked
block.setNumBytes(one.getLastByteOffsetBlock());
synchronized (dataQueue) {
lastAckedSeqno = seqno;
ackQueue.removeFirst();
dataQueue.notifyAll();
}
} catch (Exception e) {
if (!responderClosed) {
if (e instanceof IOException) {
setLastException((IOException)e);
}
hasError = true;
errorIndex = errorIndex==-1 ? 0 : errorIndex;
synchronized (dataQueue) {
dataQueue.notifyAll();
}
DFSClient.LOG.warn("DFSOutputStream ResponseProcessor exception "
+ " for block " + block, e);
responderClosed = true;
}
}
}
}
void close() {
responderClosed = true;
this.interrupt();
}
}
// If this stream has encountered any errors so far, shutdown
// threads and mark stream as closed. Returns true if we should
// sleep for a while after returning from this call.
//
private boolean processDatanodeError() throws IOException {
if (response != null) {
DFSClient.LOG.info("Error Recovery for " + block +
" waiting for responder to exit. ");
return true;
}
closeStream();
// move packets from ack queue to front of the data queue
synchronized (dataQueue) {
dataQueue.addAll(0, ackQueue);
ackQueue.clear();
}
// Record the new pipeline failure recovery.
if (lastAckedSeqnoBeforeFailure != lastAckedSeqno) {
lastAckedSeqnoBeforeFailure = lastAckedSeqno;
pipelineRecoveryCount = 1;
} else {
// If we had to recover the pipeline five times in a row for the
// same packet, this client likely has corrupt data or corrupting
// during transmission.
if (++pipelineRecoveryCount > 5) {
DFSClient.LOG.warn("Error recovering pipeline for writing " +
block + ". Already retried 5 times for the same packet.");
lastException.set(new IOException("Failing write. Tried pipeline " +
"recovery 5 times without success."));
streamerClosed = true;
return false;
}
}
boolean doSleep = setupPipelineForAppendOrRecovery();
if (!streamerClosed && dfsClient.clientRunning) {
if (stage == BlockConstructionStage.PIPELINE_CLOSE) {
// If we had an error while closing the pipeline, we go through a fast-path
// where the BlockReceiver does not run. Instead, the DataNode just finalizes
// the block immediately during the 'connect ack' process. So, we want to pull
// the end-of-block packet from the dataQueue, since we don't actually have
// a true pipeline to send it over.
//
// We also need to set lastAckedSeqno to the end-of-block Packet's seqno, so that
// a client waiting on close() will be aware that the flush finished.
synchronized (dataQueue) {
assert dataQueue.size() == 1;
Packet endOfBlockPacket = dataQueue.remove(); // remove the end of block packet
assert endOfBlockPacket.lastPacketInBlock;
assert lastAckedSeqno == endOfBlockPacket.seqno - 1;
lastAckedSeqno = endOfBlockPacket.seqno;
dataQueue.notifyAll();
}
endBlock();
} else {
initDataStreaming();
}
}
return doSleep;
}
private void setHflush() {
isHflushed = true;
}
private int findNewDatanode(final DatanodeInfo[] original
) throws IOException {
if (nodes.length != original.length + 1) {
throw new IOException(
new StringBuilder()
.append("Failed to replace a bad datanode on the existing pipeline ")
.append("due to no more good datanodes being available to try. ")
.append("(Nodes: current=").append(Arrays.asList(nodes))
.append(", original=").append(Arrays.asList(original)).append("). ")
.append("The current failed datanode replacement policy is ")
.append(dfsClient.dtpReplaceDatanodeOnFailure).append(", and ")
.append("a client may configure this via '")
.append(DFSConfigKeys.DFS_CLIENT_WRITE_REPLACE_DATANODE_ON_FAILURE_POLICY_KEY)
.append("' in its configuration.")
.toString());
}
for(int i = 0; i < nodes.length; i++) {
int j = 0;
for(; j < original.length && !nodes[i].equals(original[j]); j++);
if (j == original.length) {
return i;
}
}
throw new IOException("Failed: new datanode not found: nodes="
+ Arrays.asList(nodes) + ", original=" + Arrays.asList(original));
}
private void addDatanode2ExistingPipeline() throws IOException {
if (DataTransferProtocol.LOG.isDebugEnabled()) {
DataTransferProtocol.LOG.debug("lastAckedSeqno = " + lastAckedSeqno);
}
/*
* Is data transfer necessary? We have the following cases.
*
* Case 1: Failure in Pipeline Setup
* - Append
* + Transfer the stored replica, which may be a RBW or a finalized.
* - Create
* + If no data, then no transfer is required.
* + If there are data written, transfer RBW. This case may happens
* when there are streaming failure earlier in this pipeline.
*
* Case 2: Failure in Streaming
* - Append/Create:
* + transfer RBW
*
* Case 3: Failure in Close
* - Append/Create:
* + no transfer, let NameNode replicates the block.
*/
if (!isAppend && lastAckedSeqno < 0
&& stage == BlockConstructionStage.PIPELINE_SETUP_CREATE) {
//no data have been written
return;
} else if (stage == BlockConstructionStage.PIPELINE_CLOSE
|| stage == BlockConstructionStage.PIPELINE_CLOSE_RECOVERY) {
//pipeline is closing
return;
}
//get a new datanode
final DatanodeInfo[] original = nodes;
final LocatedBlock lb = dfsClient.namenode.getAdditionalDatanode(
src, block, nodes, failed.toArray(new DatanodeInfo[failed.size()]),
1, dfsClient.clientName);
nodes = lb.getLocations();
//find the new datanode
final int d = findNewDatanode(original);
//transfer replica
final DatanodeInfo src = d == 0? nodes[1]: nodes[d - 1];
final DatanodeInfo[] targets = {nodes[d]};
transfer(src, targets, lb.getBlockToken());
}
private void transfer(final DatanodeInfo src, final DatanodeInfo[] targets,
final Token<BlockTokenIdentifier> blockToken) throws IOException {
//transfer replica to the new datanode
Socket sock = null;
DataOutputStream out = null;
DataInputStream in = null;
try {
sock = createSocketForPipeline(src, 2, dfsClient);
final long writeTimeout = dfsClient.getDatanodeWriteTimeout(2);
OutputStream unbufOut = NetUtils.getOutputStream(sock, writeTimeout);
InputStream unbufIn = NetUtils.getInputStream(sock);
if (dfsClient.shouldEncryptData()) {
IOStreamPair encryptedStreams =
DataTransferEncryptor.getEncryptedStreams(
unbufOut, unbufIn, dfsClient.getDataEncryptionKey());
unbufOut = encryptedStreams.out;
unbufIn = encryptedStreams.in;
}
out = new DataOutputStream(new BufferedOutputStream(unbufOut,
HdfsConstants.SMALL_BUFFER_SIZE));
in = new DataInputStream(unbufIn);
//send the TRANSFER_BLOCK request
new Sender(out).transferBlock(block, blockToken, dfsClient.clientName,
targets);
out.flush();
//ack
BlockOpResponseProto response =
BlockOpResponseProto.parseFrom(PBHelper.vintPrefixed(in));
if (SUCCESS != response.getStatus()) {
throw new IOException("Failed to add a datanode");
}
} finally {
IOUtils.closeStream(in);
IOUtils.closeStream(out);
IOUtils.closeSocket(sock);
}
}
/**
* Open a DataOutputStream to a DataNode pipeline so that
* it can be written to.
* This happens when a file is appended or data streaming fails
* It keeps on trying until a pipeline is setup
*/
private boolean setupPipelineForAppendOrRecovery() throws IOException {
// check number of datanodes
if (nodes == null || nodes.length == 0) {
String msg = "Could not get block locations. " + "Source file \""
+ src + "\" - Aborting...";
DFSClient.LOG.warn(msg);
setLastException(new IOException(msg));
streamerClosed = true;
return false;
}
boolean success = false;
long newGS = 0L;
while (!success && !streamerClosed && dfsClient.clientRunning) {
boolean isRecovery = hasError;
// remove bad datanode from list of datanodes.
// If errorIndex was not set (i.e. appends), then do not remove
// any datanodes
//
if (errorIndex >= 0) {
StringBuilder pipelineMsg = new StringBuilder();
for (int j = 0; j < nodes.length; j++) {
pipelineMsg.append(nodes[j]);
if (j < nodes.length - 1) {
pipelineMsg.append(", ");
}
}
if (nodes.length <= 1) {
lastException.set(new IOException("All datanodes " + pipelineMsg
+ " are bad. Aborting..."));
streamerClosed = true;
return false;
}
DFSClient.LOG.warn("Error Recovery for block " + block +
" in pipeline " + pipelineMsg +
": bad datanode " + nodes[errorIndex]);
failed.add(nodes[errorIndex]);
DatanodeInfo[] newnodes = new DatanodeInfo[nodes.length-1];
System.arraycopy(nodes, 0, newnodes, 0, errorIndex);
System.arraycopy(nodes, errorIndex+1, newnodes, errorIndex,
newnodes.length-errorIndex);
nodes = newnodes;
hasError = false;
lastException.set(null);
errorIndex = -1;
}
// Check if replace-datanode policy is satisfied.
if (dfsClient.dtpReplaceDatanodeOnFailure.satisfy(blockReplication,
nodes, isAppend, isHflushed)) {
addDatanode2ExistingPipeline();
}
// get a new generation stamp and an access token
LocatedBlock lb = dfsClient.namenode.updateBlockForPipeline(block, dfsClient.clientName);
newGS = lb.getBlock().getGenerationStamp();
accessToken = lb.getBlockToken();
// set up the pipeline again with the remaining nodes
success = createBlockOutputStream(nodes, newGS, isRecovery);
}
if (success) {
// update pipeline at the namenode
ExtendedBlock newBlock = new ExtendedBlock(
block.getBlockPoolId(), block.getBlockId(), block.getNumBytes(), newGS);
dfsClient.namenode.updatePipeline(dfsClient.clientName, block, newBlock, nodes);
// update client side generation stamp
block = newBlock;
}
return false; // do not sleep, continue processing
}
/**
* Open a DataOutputStream to a DataNode so that it can be written to.
* This happens when a file is created and each time a new block is allocated.
* Must get block ID and the IDs of the destinations from the namenode.
* Returns the list of target datanodes.
*/
private DatanodeInfo[] nextBlockOutputStream(String client) throws IOException {
LocatedBlock lb = null;
DatanodeInfo[] nodes = null;
int count = dfsClient.getConf().nBlockWriteRetry;
boolean success = false;
ExtendedBlock oldBlock = block;
do {
hasError = false;
lastException.set(null);
errorIndex = -1;
success = false;
long startTime = Time.now();
DatanodeInfo[] excluded =
excludedNodes.getAllPresent(excludedNodes.asMap().keySet())
.keySet()
.toArray(new DatanodeInfo[0]);
block = oldBlock;
lb = locateFollowingBlock(startTime,
excluded.length > 0 ? excluded : null);
block = lb.getBlock();
block.setNumBytes(0);
accessToken = lb.getBlockToken();
nodes = lb.getLocations();
//
// Connect to first DataNode in the list.
//
success = createBlockOutputStream(nodes, 0L, false);
if (!success) {
DFSClient.LOG.info("Abandoning " + block);
dfsClient.namenode.abandonBlock(block, src, dfsClient.clientName);
block = null;
DFSClient.LOG.info("Excluding datanode " + nodes[errorIndex]);
excludedNodes.put(nodes[errorIndex], nodes[errorIndex]);
}
} while (!success && --count >= 0);
if (!success) {
throw new IOException("Unable to create new block.");
}
return nodes;
}
// connects to the first datanode in the pipeline
// Returns true if success, otherwise return failure.
//
private boolean createBlockOutputStream(DatanodeInfo[] nodes, long newGS,
boolean recoveryFlag) {
if (nodes.length == 0) {
DFSClient.LOG.info("nodes are empty for write pipeline of block "
+ block);
return false;
}
Status pipelineStatus = SUCCESS;
String firstBadLink = "";
if (DFSClient.LOG.isDebugEnabled()) {
for (int i = 0; i < nodes.length; i++) {
DFSClient.LOG.debug("pipeline = " + nodes[i]);
}
}
// persist blocks on namenode on next flush
persistBlocks.set(true);
int refetchEncryptionKey = 1;
while (true) {
boolean result = false;
DataOutputStream out = null;
try {
assert null == s : "Previous socket unclosed";
assert null == blockReplyStream : "Previous blockReplyStream unclosed";
s = createSocketForPipeline(nodes[0], nodes.length, dfsClient);
long writeTimeout = dfsClient.getDatanodeWriteTimeout(nodes.length);
OutputStream unbufOut = NetUtils.getOutputStream(s, writeTimeout);
InputStream unbufIn = NetUtils.getInputStream(s);
if (dfsClient.shouldEncryptData()) {
IOStreamPair encryptedStreams =
DataTransferEncryptor.getEncryptedStreams(unbufOut,
unbufIn, dfsClient.getDataEncryptionKey());
unbufOut = encryptedStreams.out;
unbufIn = encryptedStreams.in;
}
out = new DataOutputStream(new BufferedOutputStream(unbufOut,
HdfsConstants.SMALL_BUFFER_SIZE));
blockReplyStream = new DataInputStream(unbufIn);
//
// Xmit header info to datanode
//
// send the request
new Sender(out).writeBlock(block, accessToken, dfsClient.clientName,
nodes, null, recoveryFlag? stage.getRecoveryStage() : stage,
nodes.length, block.getNumBytes(), bytesSent, newGS, checksum,
cachingStrategy);
// receive ack for connect
BlockOpResponseProto resp = BlockOpResponseProto.parseFrom(
PBHelper.vintPrefixed(blockReplyStream));
pipelineStatus = resp.getStatus();
firstBadLink = resp.getFirstBadLink();
if (pipelineStatus != SUCCESS) {
if (pipelineStatus == Status.ERROR_ACCESS_TOKEN) {
throw new InvalidBlockTokenException(
"Got access token error for connect ack with firstBadLink as "
+ firstBadLink);
} else {
throw new IOException("Bad connect ack with firstBadLink as "
+ firstBadLink);
}
}
assert null == blockStream : "Previous blockStream unclosed";
blockStream = out;
result = true; // success
} catch (IOException ie) {
DFSClient.LOG.info("Exception in createBlockOutputStream", ie);
if (ie instanceof InvalidEncryptionKeyException && refetchEncryptionKey > 0) {
DFSClient.LOG.info("Will fetch a new encryption key and retry, "
+ "encryption key was invalid when connecting to "
+ nodes[0] + " : " + ie);
// The encryption key used is invalid.
refetchEncryptionKey--;
dfsClient.clearDataEncryptionKey();
// Don't close the socket/exclude this node just yet. Try again with
// a new encryption key.
continue;
}
// find the datanode that matches
if (firstBadLink.length() != 0) {
for (int i = 0; i < nodes.length; i++) {
// NB: Unconditionally using the xfer addr w/o hostname
if (firstBadLink.equals(nodes[i].getXferAddr())) {
errorIndex = i;
break;
}
}
} else {
errorIndex = 0;
}
hasError = true;
setLastException(ie);
result = false; // error
} finally {
if (!result) {
IOUtils.closeSocket(s);
s = null;
IOUtils.closeStream(out);
out = null;
IOUtils.closeStream(blockReplyStream);
blockReplyStream = null;
}
}
return result;
}
}
private LocatedBlock locateFollowingBlock(long start,
DatanodeInfo[] excludedNodes)
throws IOException, UnresolvedLinkException {
int retries = dfsClient.getConf().nBlockWriteLocateFollowingRetry;
long sleeptime = 400;
while (true) {
long localstart = Time.now();
while (true) {
try {
return dfsClient.namenode.addBlock(src, dfsClient.clientName,
block, excludedNodes, fileId, favoredNodes);
} catch (RemoteException e) {
IOException ue =
e.unwrapRemoteException(FileNotFoundException.class,
AccessControlException.class,
NSQuotaExceededException.class,
DSQuotaExceededException.class,
UnresolvedPathException.class);
if (ue != e) {
throw ue; // no need to retry these exceptions
}
if (NotReplicatedYetException.class.getName().
equals(e.getClassName())) {
if (retries == 0) {
throw e;
} else {
--retries;
DFSClient.LOG.info("Exception while adding a block", e);
if (Time.now() - localstart > 5000) {
DFSClient.LOG.info("Waiting for replication for "
+ (Time.now() - localstart) / 1000
+ " seconds");
}
try {
DFSClient.LOG.warn("NotReplicatedYetException sleeping " + src
+ " retries left " + retries);
Thread.sleep(sleeptime);
sleeptime *= 2;
} catch (InterruptedException ie) {
}
}
} else {
throw e;
}
}
}
}
}
ExtendedBlock getBlock() {
return block;
}
DatanodeInfo[] getNodes() {
return nodes;
}
Token<BlockTokenIdentifier> getBlockToken() {
return accessToken;
}
private void setLastException(IOException e) {
lastException.compareAndSet(null, e);
}
}
/**
* Create a socket for a write pipeline
* @param first the first datanode
* @param length the pipeline length
* @param client
* @return the socket connected to the first datanode
*/
static Socket createSocketForPipeline(final DatanodeInfo first,
final int length, final DFSClient client) throws IOException {
final String dnAddr = first.getXferAddr(
client.getConf().connectToDnViaHostname);
if (DFSClient.LOG.isDebugEnabled()) {
DFSClient.LOG.debug("Connecting to datanode " + dnAddr);
}
final InetSocketAddress isa = NetUtils.createSocketAddr(dnAddr);
final Socket sock = client.socketFactory.createSocket();
final int timeout = client.getDatanodeReadTimeout(length);
NetUtils.connect(sock, isa, client.getRandomLocalInterfaceAddr(), client.getConf().socketTimeout);
sock.setSoTimeout(timeout);
sock.setSendBufferSize(HdfsConstants.DEFAULT_DATA_SOCKET_SIZE);
if(DFSClient.LOG.isDebugEnabled()) {
DFSClient.LOG.debug("Send buf size " + sock.getSendBufferSize());
}
return sock;
}
protected void checkClosed() throws IOException {
if (closed) {
IOException e = lastException.get();
throw e != null ? e : new ClosedChannelException();
}
}
//
// returns the list of targets, if any, that is being currently used.
//
@VisibleForTesting
public synchronized DatanodeInfo[] getPipeline() {
if (streamer == null) {
return null;
}
DatanodeInfo[] currentNodes = streamer.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;
}
private DFSOutputStream(DFSClient dfsClient, String src, Progressable progress,
HdfsFileStatus stat, DataChecksum checksum) throws IOException {
super(checksum, checksum.getBytesPerChecksum(), checksum.getChecksumSize());
this.dfsClient = dfsClient;
this.src = src;
this.fileId = stat.getFileId();
this.blockSize = stat.getBlockSize();
this.blockReplication = stat.getReplication();
this.progress = progress;
this.cachingStrategy =
dfsClient.getDefaultWriteCachingStrategy().duplicate();
if ((progress != null) && DFSClient.LOG.isDebugEnabled()) {
DFSClient.LOG.debug(
"Set non-null progress callback on DFSOutputStream " + src);
}
final int bytesPerChecksum = checksum.getBytesPerChecksum();
if ( bytesPerChecksum < 1 || blockSize % bytesPerChecksum != 0) {
throw new IOException("io.bytes.per.checksum(" + bytesPerChecksum +
") and blockSize(" + blockSize +
") do not match. " + "blockSize should be a " +
"multiple of io.bytes.per.checksum");
}
this.checksum = checksum;
}
/** Construct a new output stream for creating a file. */
private 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().writePacketSize,
checksum.getBytesPerChecksum());
streamer = new DataStreamer();
if (favoredNodes != null && favoredNodes.length != 0) {
streamer.setFavoredNodes(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 {
final HdfsFileStatus stat;
try {
stat = dfsClient.namenode.create(src, masked, dfsClient.clientName,
new EnumSetWritable<CreateFlag>(flag), createParent, replication,
blockSize);
} catch(RemoteException re) {
throw re.unwrapRemoteException(AccessControlException.class,
DSQuotaExceededException.class,
FileAlreadyExistsException.class,
FileNotFoundException.class,
ParentNotDirectoryException.class,
NSQuotaExceededException.class,
SafeModeException.class,
UnresolvedPathException.class,
SnapshotAccessControlException.class);
}
final DFSOutputStream out = new DFSOutputStream(dfsClient, src, stat,
flag, progress, checksum, favoredNodes);
out.start();
return out;
}
static DFSOutputStream newStreamForCreate(DFSClient dfsClient, String src,
FsPermission masked, EnumSet<CreateFlag> flag, boolean createParent,
short replication, long blockSize, Progressable progress, int buffersize,
DataChecksum checksum) throws IOException {
return newStreamForCreate(dfsClient, src, masked, flag, createParent, replication,
blockSize, progress, buffersize, checksum, null);
}
/** Construct a new output stream for append. */
private DFSOutputStream(DFSClient dfsClient, String src,
Progressable progress, LocatedBlock lastBlock, HdfsFileStatus stat,
DataChecksum checksum) throws IOException {
this(dfsClient, src, progress, stat, checksum);
initialFileSize = stat.getLen(); // length of file when opened
// The last partial block of the file has to be filled.
if (lastBlock != null) {
// indicate that we are appending to an existing block
bytesCurBlock = lastBlock.getBlockSize();
streamer = new DataStreamer(lastBlock, stat, checksum.getBytesPerChecksum());
} else {
computePacketChunkSize(dfsClient.getConf().writePacketSize,
checksum.getBytesPerChecksum());
streamer = new DataStreamer();
}
}
static DFSOutputStream newStreamForAppend(DFSClient dfsClient, String src,
int buffersize, Progressable progress, LocatedBlock lastBlock,
HdfsFileStatus stat, DataChecksum checksum) throws IOException {
final DFSOutputStream out = new DFSOutputStream(dfsClient, src,
progress, lastBlock, stat, checksum);
out.start();
return out;
}
private void computePacketChunkSize(int psize, int csize) {
int chunkSize = csize + checksum.getChecksumSize();
chunksPerPacket = Math.max(psize/chunkSize, 1);
packetSize = chunkSize*chunksPerPacket;
if (DFSClient.LOG.isDebugEnabled()) {
DFSClient.LOG.debug("computePacketChunkSize: src=" + src +
", chunkSize=" + chunkSize +
", chunksPerPacket=" + chunksPerPacket +
", packetSize=" + packetSize);
}
}
private void queueCurrentPacket() {
synchronized (dataQueue) {
if (currentPacket == null) return;
dataQueue.addLast(currentPacket);
lastQueuedSeqno = currentPacket.seqno;
if (DFSClient.LOG.isDebugEnabled()) {
DFSClient.LOG.debug("Queued packet " + currentPacket.seqno);
}
currentPacket = null;
dataQueue.notifyAll();
}
}
private void waitAndQueueCurrentPacket() throws IOException {
synchronized (dataQueue) {
try {
// If queue is full, then wait till we have enough space
while (!closed && dataQueue.size() + ackQueue.size() > MAX_PACKETS) {
try {
dataQueue.wait();
} catch (InterruptedException e) {
// If we get interrupted while waiting to queue data, we still need to get rid
// of the current packet. This is because we have an invariant that if
// currentPacket gets full, it will get queued before the next writeChunk.
//
// Rather than wait around for space in the queue, we should instead try to
// return to the caller as soon as possible, even though we slightly overrun
// the MAX_PACKETS iength.
Thread.currentThread().interrupt();
break;
}
}
checkClosed();
queueCurrentPacket();
} catch (ClosedChannelException e) {
}
}
}
// @see FSOutputSummer#writeChunk()
@Override
protected synchronized void writeChunk(byte[] b, int offset, int len, byte[] checksum)
throws IOException {
dfsClient.checkOpen();
checkClosed();
int cklen = checksum.length;
int bytesPerChecksum = this.checksum.getBytesPerChecksum();
if (len > bytesPerChecksum) {
throw new IOException("writeChunk() buffer size is " + len +
" is larger than supported bytesPerChecksum " +
bytesPerChecksum);
}
if (checksum.length != this.checksum.getChecksumSize()) {
throw new IOException("writeChunk() checksum size is supposed to be " +
this.checksum.getChecksumSize() +
" but found to be " + checksum.length);
}
if (currentPacket == null) {
currentPacket = new Packet(packetSize, chunksPerPacket,
bytesCurBlock);
if (DFSClient.LOG.isDebugEnabled()) {
DFSClient.LOG.debug("DFSClient writeChunk allocating new packet seqno=" +
currentPacket.seqno +
", src=" + src +
", packetSize=" + packetSize +
", chunksPerPacket=" + chunksPerPacket +
", bytesCurBlock=" + bytesCurBlock);
}
}
currentPacket.writeChecksum(checksum, 0, cklen);
currentPacket.writeData(b, offset, len);
currentPacket.numChunks++;
bytesCurBlock += len;
// If packet is full, enqueue it for transmission
//
if (currentPacket.numChunks == currentPacket.maxChunks ||
bytesCurBlock == blockSize) {
if (DFSClient.LOG.isDebugEnabled()) {
DFSClient.LOG.debug("DFSClient writeChunk packet full seqno=" +
currentPacket.seqno +
", src=" + src +
", bytesCurBlock=" + bytesCurBlock +
", blockSize=" + blockSize +
", appendChunk=" + appendChunk);
}
waitAndQueueCurrentPacket();
// 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.
if (appendChunk && bytesCurBlock%bytesPerChecksum == 0) {
appendChunk = false;
resetChecksumChunk(bytesPerChecksum);
}
if (!appendChunk) {
int psize = Math.min((int)(blockSize-bytesCurBlock), dfsClient.getConf().writePacketSize);
computePacketChunkSize(psize, bytesPerChecksum);
}
//
// if encountering a block boundary, send an empty packet to
// indicate the end of block and reset bytesCurBlock.
//
if (bytesCurBlock == blockSize) {
currentPacket = new Packet(0, 0, bytesCurBlock);
currentPacket.lastPacketInBlock = true;
currentPacket.syncBlock = shouldSyncBlock;
waitAndQueueCurrentPacket();
bytesCurBlock = 0;
lastFlushOffset = 0;
}
}
}
@Override
@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 {
flushOrSync(false, EnumSet.noneOf(SyncFlag.class));
}
@Override
public void hsync() throws IOException {
hsync(EnumSet.noneOf(SyncFlag.class));
}
/**
* 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 {
flushOrSync(true, syncFlags);
}
/**
* 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);
synchronized (this) {
/* Record current blockOffset. This might be changed inside
* flushBuffer() where a partial checksum chunk might be flushed.
* After the flush, reset the bytesCurBlock back to its previous value,
* any partial checksum chunk will be sent now and in next packet.
*/
long saveOffset = bytesCurBlock;
Packet oldCurrentPacket = currentPacket;
// flush checksum buffer, but keep checksum buffer intact
flushBuffer(true);
// bytesCurBlock potentially incremented if there was buffered data
if (DFSClient.LOG.isDebugEnabled()) {
DFSClient.LOG.debug(
"DFSClient flush() : saveOffset " + saveOffset +
" bytesCurBlock " + bytesCurBlock +
" lastFlushOffset " + lastFlushOffset);
}
// Flush only if we haven't already flushed till this offset.
if (lastFlushOffset != bytesCurBlock) {
assert bytesCurBlock > lastFlushOffset;
// record the valid offset of this flush
lastFlushOffset = bytesCurBlock;
if (isSync && currentPacket == null) {
// Nothing to send right now,
// but sync was requested.
// Send an empty packet
currentPacket = new Packet(packetSize, chunksPerPacket,
bytesCurBlock);
}
} else {
// We already flushed up to this offset.
// This means that we haven't written anything since the last flush
// (or the beginning of the file). Hence, we should not have any
// packet queued prior to this call, since the last flush set
// currentPacket = null.
assert oldCurrentPacket == null :
"Empty flush should not occur with a currentPacket";
if (isSync && bytesCurBlock > 0) {
// Nothing to send right now,
// and the block was partially written,
// and sync was requested.
// So send an empty sync packet.
currentPacket = new Packet(packetSize, chunksPerPacket,
bytesCurBlock);
} else {
// just discard the current packet since it is already been sent.
currentPacket = null;
}
}
if (currentPacket != null) {
currentPacket.syncBlock = isSync;
waitAndQueueCurrentPacket();
}
// Restore state of stream. Record the last flush offset
// of the last full chunk that was flushed.
//
bytesCurBlock = saveOffset;
toWaitFor = lastQueuedSeqno;
} // end synchronized
waitForAckedSeqno(toWaitFor);
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, 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 (streamer != null) {
streamer.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 (!closed) {
lastException.set(new IOException("IOException flush:" + 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 (streamer == null) {
return blockReplication; // no pipeline, return repl factor of file
}
DatanodeInfo[] currentNodes = streamer.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.
*/
private void flushInternal() throws IOException {
long toWaitFor;
synchronized (this) {
dfsClient.checkOpen();
checkClosed();
//
// If there is data in the current buffer, send it across
//
queueCurrentPacket();
toWaitFor = lastQueuedSeqno;
}
waitForAckedSeqno(toWaitFor);
}
private void waitForAckedSeqno(long seqno) throws IOException {
if (DFSClient.LOG.isDebugEnabled()) {
DFSClient.LOG.debug("Waiting for ack for: " + seqno);
}
try {
synchronized (dataQueue) {
while (!closed) {
checkClosed();
if (lastAckedSeqno >= seqno) {
break;
}
try {
dataQueue.wait(1000); // when we receive an ack, we notify on
// dataQueue
} catch (InterruptedException ie) {
throw new InterruptedIOException(
"Interrupted while waiting for data to be acknowledged by pipeline");
}
}
}
checkClosed();
} catch (ClosedChannelException e) {
}
}
private synchronized void start() {
streamer.start();
}
/**
* Aborts this output stream and releases any system
* resources associated with this stream.
*/
synchronized void abort() throws IOException {
if (closed) {
return;
}
streamer.setLastException(new IOException("Lease timeout of "
+ (dfsClient.getHdfsTimeout()/1000) + " seconds expired."));
closeThreads(true);
dfsClient.endFileLease(src);
}
// shutdown datastreamer and responseprocessor threads.
// interrupt datastreamer if force is true
private void closeThreads(boolean force) throws IOException {
try {
streamer.close(force);
streamer.join();
if (s != null) {
s.close();
}
} catch (InterruptedException e) {
throw new IOException("Failed to shutdown streamer");
} finally {
streamer = null;
s = null;
closed = true;
}
}
/**
* Closes this output stream and releases any system
* resources associated with this stream.
*/
@Override
public synchronized void close() throws IOException {
if (closed) {
IOException e = lastException.getAndSet(null);
if (e == null)
return;
else
throw e;
}
try {
flushBuffer(); // flush from all upper layers
if (currentPacket != null) {
waitAndQueueCurrentPacket();
}
if (bytesCurBlock != 0) {
// send an empty packet to mark the end of the block
currentPacket = new Packet(0, 0, bytesCurBlock);
currentPacket.lastPacketInBlock = true;
currentPacket.syncBlock = shouldSyncBlock;
}
flushInternal(); // flush all data to Datanodes
// get last block before destroying the streamer
ExtendedBlock lastBlock = streamer.getBlock();
closeThreads(false);
completeFile(lastBlock);
dfsClient.endFileLease(src);
} catch (ClosedChannelException e) {
} finally {
closed = true;
}
}
// should be called holding (this) lock since setTestFilename() may
// be called during unit tests
private void completeFile(ExtendedBlock last) throws IOException {
long localstart = Time.now();
boolean fileComplete = false;
while (!fileComplete) {
fileComplete =
dfsClient.namenode.complete(src, dfsClient.clientName, last, fileId);
if (!fileComplete) {
final int hdfsTimeout = dfsClient.getHdfsTimeout();
if (!dfsClient.clientRunning ||
(hdfsTimeout > 0 && localstart + hdfsTimeout < Time.now())) {
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 {
Thread.sleep(400);
if (Time.now() - localstart > 5000) {
DFSClient.LOG.info("Could not complete " + src + " retrying...");
}
} catch (InterruptedException ie) {
}
}
}
}
@VisibleForTesting
public void setArtificialSlowdown(long period) {
artificialSlowdown = period;
}
@VisibleForTesting
public synchronized void setChunksPerPacket(int value) {
chunksPerPacket = Math.min(chunksPerPacket, value);
packetSize = (checksum.getBytesPerChecksum() +
checksum.getChecksumSize()) * chunksPerPacket;
}
synchronized void setTestFilename(String newname) {
src = newname;
}
/**
* Returns the size of a file as it was when this stream was opened
*/
long getInitialLen() {
return initialFileSize;
}
/**
* Returns the access token currently used by streamer, for testing only
*/
synchronized Token<BlockTokenIdentifier> getBlockToken() {
return streamer.getBlockToken();
}
@Override
public void setDropBehind(Boolean dropBehind) throws IOException {
this.cachingStrategy.setDropBehind(dropBehind);
}
}