/**
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.hadoop.hdfs.server.namenode;
import java.io.BufferedInputStream;
import java.io.DataInput;
import java.io.DataInputStream;
import java.io.DataOutput;
import java.io.EOFException;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.RandomAccessFile;
import java.util.ArrayList;
import java.util.Iterator;
import java.lang.Math;
import java.nio.channels.FileChannel;
import java.nio.ByteBuffer;
import org.apache.hadoop.hdfs.protocol.Block;
import org.apache.hadoop.hdfs.protocol.DatanodeID;
import org.apache.hadoop.hdfs.protocol.FSConstants;
import org.apache.hadoop.hdfs.server.common.Storage;
import org.apache.hadoop.hdfs.server.common.Storage.StorageDirectory;
import org.apache.hadoop.hdfs.server.namenode.FSImage.NameNodeDirType;
import org.apache.hadoop.hdfs.server.namenode.metrics.NameNodeMetrics;
import org.apache.hadoop.io.*;
import org.apache.hadoop.fs.FileStatus;
import org.apache.hadoop.fs.permission.*;
/**
* FSEditLog maintains a log of the namespace modifications.
*
*/
public class FSEditLog {
private static final byte OP_INVALID = -1;
private static final byte OP_ADD = 0;
private static final byte OP_RENAME = 1; // rename
private static final byte OP_DELETE = 2; // delete
private static final byte OP_MKDIR = 3; // create directory
private static final byte OP_SET_REPLICATION = 4; // set replication
//the following two are used only for backward compatibility :
@Deprecated private static final byte OP_DATANODE_ADD = 5;
@Deprecated private static final byte OP_DATANODE_REMOVE = 6;
private static final byte OP_SET_PERMISSIONS = 7;
private static final byte OP_SET_OWNER = 8;
private static final byte OP_CLOSE = 9; // close after write
private static final byte OP_SET_GENSTAMP = 10; // store genstamp
/* The following two are not used any more. Should be removed once
* LAST_UPGRADABLE_LAYOUT_VERSION is -17 or newer. */
private static final byte OP_SET_NS_QUOTA = 11; // set namespace quota
private static final byte OP_CLEAR_NS_QUOTA = 12; // clear namespace quota
private static final byte OP_TIMES = 13; // sets mod & access time on a file
private static final byte OP_SET_QUOTA = 14; // sets name and disk quotas.
private static int sizeFlushBuffer = 512*1024;
private ArrayList<EditLogOutputStream> editStreams = null;
private FSImage fsimage = null;
// a monotonically increasing counter that represents transactionIds.
private long txid = 0;
// stores the last synced transactionId.
private long synctxid = 0;
// the time of printing the statistics to the log file.
private long lastPrintTime;
// is a sync currently running?
private boolean isSyncRunning;
// these are statistics counters.
private long numTransactions; // number of transactions
private long numTransactionsBatchedInSync;
private long totalTimeTransactions; // total time for all transactions
private NameNodeMetrics metrics;
private static class TransactionId {
public long txid;
TransactionId(long value) {
this.txid = value;
}
}
// stores the most current transactionId of this thread.
private static final ThreadLocal<TransactionId> myTransactionId = new ThreadLocal<TransactionId>() {
protected synchronized TransactionId initialValue() {
return new TransactionId(Long.MAX_VALUE);
}
};
/**
* An implementation of the abstract class {@link EditLogOutputStream},
* which stores edits in a local file.
*/
static private class EditLogFileOutputStream extends EditLogOutputStream {
private File file;
private FileOutputStream fp; // file stream for storing edit logs
private FileChannel fc; // channel of the file stream for sync
private DataOutputBuffer bufCurrent; // current buffer for writing
private DataOutputBuffer bufReady; // buffer ready for flushing
static ByteBuffer fill = ByteBuffer.allocateDirect(512); // preallocation
EditLogFileOutputStream(File name) throws IOException {
super();
file = name;
bufCurrent = new DataOutputBuffer(sizeFlushBuffer);
bufReady = new DataOutputBuffer(sizeFlushBuffer);
RandomAccessFile rp = new RandomAccessFile(name, "rw");
fp = new FileOutputStream(rp.getFD()); // open for append
fc = rp.getChannel();
fc.position(fc.size());
}
@Override
String getName() {
return file.getPath();
}
/** {@inheritDoc} */
@Override
public void write(int b) throws IOException {
bufCurrent.write(b);
}
/** {@inheritDoc} */
@Override
void write(byte op, Writable ... writables) throws IOException {
write(op);
for(Writable w : writables) {
w.write(bufCurrent);
}
}
/**
* Create empty edits logs file.
*/
@Override
void create() throws IOException {
fc.truncate(0);
fc.position(0);
bufCurrent.writeInt(FSConstants.LAYOUT_VERSION);
setReadyToFlush();
flush();
}
@Override
public void close() throws IOException {
// close should have been called after all pending transactions
// have been flushed & synced.
int bufSize = bufCurrent.size();
if (bufSize != 0) {
throw new IOException("FSEditStream has " + bufSize +
" bytes still to be flushed and cannot " +
"be closed.");
}
bufCurrent.close();
bufReady.close();
// remove the last INVALID marker from transaction log.
fc.truncate(fc.position());
fp.close();
bufCurrent = bufReady = null;
}
/**
* All data that has been written to the stream so far will be flushed.
* New data can be still written to the stream while flushing is performed.
*/
@Override
void setReadyToFlush() throws IOException {
assert bufReady.size() == 0 : "previous data is not flushed yet";
write(OP_INVALID); // insert end-of-file marker
DataOutputBuffer tmp = bufReady;
bufReady = bufCurrent;
bufCurrent = tmp;
}
/**
* Flush ready buffer to persistent store.
* currentBuffer is not flushed as it accumulates new log records
* while readyBuffer will be flushed and synced.
*/
@Override
protected void flushAndSync() throws IOException {
preallocate(); // preallocate file if necessary
bufReady.writeTo(fp); // write data to file
bufReady.reset(); // erase all data in the buffer
fc.force(false); // metadata updates not needed because of preallocation
fc.position(fc.position()-1); // skip back the end-of-file marker
}
/**
* Return the size of the current edit log including buffered data.
*/
@Override
long length() throws IOException {
// file size + size of both buffers
return fc.size() + bufReady.size() + bufCurrent.size();
}
// allocate a big chunk of data
private void preallocate() throws IOException {
long position = fc.position();
if (position + 4096 >= fc.size()) {
FSNamesystem.LOG.debug("Preallocating Edit log, current size " +
fc.size());
long newsize = position + 1024*1024; // 1MB
fill.position(0);
int written = fc.write(fill, newsize);
FSNamesystem.LOG.debug("Edit log size is now " + fc.size() +
" written " + written + " bytes " +
" at offset " + newsize);
}
}
/**
* Returns the file associated with this stream
*/
File getFile() {
return file;
}
}
static class EditLogFileInputStream extends EditLogInputStream {
private File file;
private FileInputStream fStream;
EditLogFileInputStream(File name) throws IOException {
file = name;
fStream = new FileInputStream(name);
}
@Override
String getName() {
return file.getPath();
}
@Override
public int available() throws IOException {
return fStream.available();
}
@Override
public int read() throws IOException {
return fStream.read();
}
@Override
public int read(byte[] b, int off, int len) throws IOException {
return fStream.read(b, off, len);
}
@Override
public void close() throws IOException {
fStream.close();
}
@Override
long length() throws IOException {
// file size + size of both buffers
return file.length();
}
}
FSEditLog(FSImage image) {
fsimage = image;
isSyncRunning = false;
metrics = NameNode.getNameNodeMetrics();
lastPrintTime = FSNamesystem.now();
}
private File getEditFile(StorageDirectory sd) {
return fsimage.getEditFile(sd);
}
private File getEditNewFile(StorageDirectory sd) {
return fsimage.getEditNewFile(sd);
}
private int getNumStorageDirs() {
int numStorageDirs = 0;
for (Iterator<StorageDirectory> it =
fsimage.dirIterator(NameNodeDirType.EDITS); it.hasNext(); it.next())
numStorageDirs++;
return numStorageDirs;
}
synchronized int getNumEditStreams() {
return editStreams == null ? 0 : editStreams.size();
}
boolean isOpen() {
return getNumEditStreams() > 0;
}
/**
* Create empty edit log files.
* Initialize the output stream for logging.
*
* @throws IOException
*/
public synchronized void open() throws IOException {
numTransactions = totalTimeTransactions = numTransactionsBatchedInSync = 0;
if (editStreams == null)
editStreams = new ArrayList<EditLogOutputStream>();
for (Iterator<StorageDirectory> it =
fsimage.dirIterator(NameNodeDirType.EDITS); it.hasNext();) {
StorageDirectory sd = it.next();
File eFile = getEditFile(sd);
try {
EditLogOutputStream eStream = new EditLogFileOutputStream(eFile);
editStreams.add(eStream);
} catch (IOException e) {
FSNamesystem.LOG.warn("Unable to open edit log file " + eFile);
// Remove the directory from list of storage directories
it.remove();
}
}
}
public synchronized void createEditLogFile(File name) throws IOException {
EditLogOutputStream eStream = new EditLogFileOutputStream(name);
eStream.create();
eStream.close();
}
/**
* Create edits.new if non existent.
*/
synchronized void createNewIfMissing() throws IOException {
for (Iterator<StorageDirectory> it =
fsimage.dirIterator(NameNodeDirType.EDITS); it.hasNext();) {
File newFile = getEditNewFile(it.next());
if (!newFile.exists())
createEditLogFile(newFile);
}
}
/**
* Shutdown the file store.
*/
public synchronized void close() throws IOException {
while (isSyncRunning) {
try {
wait(1000);
} catch (InterruptedException ie) {
}
}
if (editStreams == null) {
return;
}
printStatistics(true);
numTransactions = totalTimeTransactions = numTransactionsBatchedInSync = 0;
for (int idx = 0; idx < editStreams.size(); idx++) {
EditLogOutputStream eStream = editStreams.get(idx);
try {
eStream.setReadyToFlush();
eStream.flush();
eStream.close();
} catch (IOException e) {
processIOError(idx);
idx--;
}
}
editStreams.clear();
}
/**
* If there is an IO Error on any log operations, remove that
* directory from the list of directories.
* If no more directories remain, then exit.
*/
synchronized void processIOError(int index) {
if (editStreams == null || editStreams.size() <= 1) {
FSNamesystem.LOG.fatal(
"Fatal Error : All storage directories are inaccessible.");
Runtime.getRuntime().exit(-1);
}
assert(index < getNumStorageDirs());
assert(getNumStorageDirs() == editStreams.size());
File parentStorageDir = ((EditLogFileOutputStream)editStreams
.get(index)).getFile()
.getParentFile().getParentFile();
editStreams.remove(index);
//
// Invoke the ioerror routine of the fsimage
//
fsimage.processIOError(parentStorageDir);
}
/**
* If there is an IO Error on any log operations on storage directory,
* remove any stream associated with that directory
*/
synchronized void processIOError(StorageDirectory sd) {
// Try to remove stream only if one should exist
if (!sd.getStorageDirType().isOfType(NameNodeDirType.EDITS))
return;
if (editStreams == null || editStreams.size() <= 1) {
FSNamesystem.LOG.fatal(
"Fatal Error : All storage directories are inaccessible.");
Runtime.getRuntime().exit(-1);
}
for (int idx = 0; idx < editStreams.size(); idx++) {
File parentStorageDir = ((EditLogFileOutputStream)editStreams
.get(idx)).getFile()
.getParentFile().getParentFile();
if (parentStorageDir.getName().equals(sd.getRoot().getName()))
editStreams.remove(idx);
}
}
/**
* The specified streams have IO errors. Remove them from logging
* new transactions.
*/
private void processIOError(ArrayList<EditLogOutputStream> errorStreams) {
if (errorStreams == null) {
return; // nothing to do
}
for (int idx = 0; idx < errorStreams.size(); idx++) {
EditLogOutputStream eStream = errorStreams.get(idx);
int j = 0;
int numEditStreams = editStreams.size();
for (j = 0; j < numEditStreams; j++) {
if (editStreams.get(j) == eStream) {
break;
}
}
if (j == numEditStreams) {
FSNamesystem.LOG.error("Unable to find sync log on which " +
" IO error occured. " +
"Fatal Error.");
Runtime.getRuntime().exit(-1);
}
processIOError(j);
}
fsimage.incrementCheckpointTime();
}
/**
* check if ANY edits.new log exists
*/
boolean existsNew() throws IOException {
for (Iterator<StorageDirectory> it =
fsimage.dirIterator(NameNodeDirType.EDITS); it.hasNext();) {
if (getEditNewFile(it.next()).exists()) {
return true;
}
}
return false;
}
/**
* Load an edit log, and apply the changes to the in-memory structure
* This is where we apply edits that we've been writing to disk all
* along.
*/
static int loadFSEdits(EditLogInputStream edits) throws IOException {
FSNamesystem fsNamesys = FSNamesystem.getFSNamesystem();
FSDirectory fsDir = fsNamesys.dir;
int numEdits = 0;
int logVersion = 0;
String clientName = null;
String clientMachine = null;
String path = null;
int numOpAdd = 0, numOpClose = 0, numOpDelete = 0,
numOpRename = 0, numOpSetRepl = 0, numOpMkDir = 0,
numOpSetPerm = 0, numOpSetOwner = 0, numOpSetGenStamp = 0,
numOpTimes = 0, numOpOther = 0;
long startTime = FSNamesystem.now();
DataInputStream in = new DataInputStream(new BufferedInputStream(edits));
try {
// Read log file version. Could be missing.
in.mark(4);
// If edits log is greater than 2G, available method will return negative
// numbers, so we avoid having to call available
boolean available = true;
try {
logVersion = in.readByte();
} catch (EOFException e) {
available = false;
}
if (available) {
in.reset();
logVersion = in.readInt();
if (logVersion < FSConstants.LAYOUT_VERSION) // future version
throw new IOException(
"Unexpected version of the file system log file: "
+ logVersion + ". Current version = "
+ FSConstants.LAYOUT_VERSION + ".");
}
assert logVersion <= Storage.LAST_UPGRADABLE_LAYOUT_VERSION :
"Unsupported version " + logVersion;
while (true) {
long timestamp = 0;
long mtime = 0;
long atime = 0;
long blockSize = 0;
byte opcode = -1;
try {
opcode = in.readByte();
if (opcode == OP_INVALID) {
FSNamesystem.LOG.info("Invalid opcode, reached end of edit log " +
"Number of transactions found " + numEdits);
break; // no more transactions
}
} catch (EOFException e) {
break; // no more transactions
}
numEdits++;
switch (opcode) {
case OP_ADD:
case OP_CLOSE: {
// versions > 0 support per file replication
// get name and replication
int length = in.readInt();
if (-7 == logVersion && length != 3||
-17 < logVersion && logVersion < -7 && length != 4 ||
logVersion <= -17 && length != 5) {
throw new IOException("Incorrect data format." +
" logVersion is " + logVersion +
" but writables.length is " +
length + ". ");
}
path = FSImage.readString(in);
short replication = adjustReplication(readShort(in));
mtime = readLong(in);
if (logVersion <= -17) {
atime = readLong(in);
}
if (logVersion < -7) {
blockSize = readLong(in);
}
// get blocks
Block blocks[] = null;
if (logVersion <= -14) {
blocks = readBlocks(in);
} else {
BlockTwo oldblk = new BlockTwo();
int num = in.readInt();
blocks = new Block[num];
for (int i = 0; i < num; i++) {
oldblk.readFields(in);
blocks[i] = new Block(oldblk.blkid, oldblk.len,
Block.GRANDFATHER_GENERATION_STAMP);
}
}
// Older versions of HDFS does not store the block size in inode.
// If the file has more than one block, use the size of the
// first block as the blocksize. Otherwise use the default
// block size.
if (-8 <= logVersion && blockSize == 0) {
if (blocks.length > 1) {
blockSize = blocks[0].getNumBytes();
} else {
long first = ((blocks.length == 1)? blocks[0].getNumBytes(): 0);
blockSize = Math.max(fsNamesys.getDefaultBlockSize(), first);
}
}
PermissionStatus permissions = fsNamesys.getUpgradePermission();
if (logVersion <= -11) {
permissions = PermissionStatus.read(in);
}
// clientname, clientMachine and block locations of last block.
if (opcode == OP_ADD && logVersion <= -12) {
clientName = FSImage.readString(in);
clientMachine = FSImage.readString(in);
if (-13 <= logVersion) {
readDatanodeDescriptorArray(in);
}
} else {
clientName = "";
clientMachine = "";
}
// The open lease transaction re-creates a file if necessary.
// Delete the file if it already exists.
if (FSNamesystem.LOG.isDebugEnabled()) {
FSNamesystem.LOG.debug(opcode + ": " + path +
" numblocks : " + blocks.length +
" clientHolder " + clientName +
" clientMachine " + clientMachine);
}
fsDir.unprotectedDelete(path, mtime);
// add to the file tree
INodeFile node = (INodeFile)fsDir.unprotectedAddFile(
path, permissions,
blocks, replication,
mtime, atime, blockSize);
if (opcode == OP_ADD) {
numOpAdd++;
//
// Replace current node with a INodeUnderConstruction.
// Recreate in-memory lease record.
//
INodeFileUnderConstruction cons = new INodeFileUnderConstruction(
node.getLocalNameBytes(),
node.getReplication(),
node.getModificationTime(),
node.getPreferredBlockSize(),
node.getBlocks(),
node.getPermissionStatus(),
clientName,
clientMachine,
null);
fsDir.replaceNode(path, node, cons);
fsNamesys.leaseManager.addLease(cons.clientName, path);
}
break;
}
case OP_SET_REPLICATION: {
numOpSetRepl++;
path = FSImage.readString(in);
short replication = adjustReplication(readShort(in));
fsDir.unprotectedSetReplication(path, replication, null);
break;
}
case OP_RENAME: {
numOpRename++;
int length = in.readInt();
if (length != 3) {
throw new IOException("Incorrect data format. "
+ "Mkdir operation.");
}
String s = FSImage.readString(in);
String d = FSImage.readString(in);
timestamp = readLong(in);
FileStatus dinfo = fsDir.getFileInfo(d);
fsDir.unprotectedRenameTo(s, d, timestamp);
fsNamesys.changeLease(s, d, dinfo);
break;
}
case OP_DELETE: {
numOpDelete++;
int length = in.readInt();
if (length != 2) {
throw new IOException("Incorrect data format. "
+ "delete operation.");
}
path = FSImage.readString(in);
timestamp = readLong(in);
fsDir.unprotectedDelete(path, timestamp);
break;
}
case OP_MKDIR: {
numOpMkDir++;
PermissionStatus permissions = fsNamesys.getUpgradePermission();
int length = in.readInt();
if (-17 < logVersion && length != 2 ||
logVersion <= -17 && length != 3) {
throw new IOException("Incorrect data format. "
+ "Mkdir operation.");
}
path = FSImage.readString(in);
timestamp = readLong(in);
// The disk format stores atimes for directories as well.
// However, currently this is not being updated/used because of
// performance reasons.
if (logVersion <= -17) {
atime = readLong(in);
}
if (logVersion <= -11) {
permissions = PermissionStatus.read(in);
}
fsDir.unprotectedMkdir(path, permissions, timestamp);
break;
}
case OP_SET_GENSTAMP: {
numOpSetGenStamp++;
long lw = in.readLong();
fsDir.namesystem.setGenerationStamp(lw);
break;
}
case OP_DATANODE_ADD: {
numOpOther++;
FSImage.DatanodeImage nodeimage = new FSImage.DatanodeImage();
nodeimage.readFields(in);
//Datnodes are not persistent any more.
break;
}
case OP_DATANODE_REMOVE: {
numOpOther++;
DatanodeID nodeID = new DatanodeID();
nodeID.readFields(in);
//Datanodes are not persistent any more.
break;
}
case OP_SET_PERMISSIONS: {
numOpSetPerm++;
if (logVersion > -11)
throw new IOException("Unexpected opcode " + opcode
+ " for version " + logVersion);
fsDir.unprotectedSetPermission(
FSImage.readString(in), FsPermission.read(in));
break;
}
case OP_SET_OWNER: {
numOpSetOwner++;
if (logVersion > -11)
throw new IOException("Unexpected opcode " + opcode
+ " for version " + logVersion);
fsDir.unprotectedSetOwner(FSImage.readString(in),
FSImage.readString_EmptyAsNull(in),
FSImage.readString_EmptyAsNull(in));
break;
}
case OP_SET_NS_QUOTA: {
if (logVersion > -16) {
throw new IOException("Unexpected opcode " + opcode
+ " for version " + logVersion);
}
fsDir.unprotectedSetQuota(FSImage.readString(in),
readLongWritable(in),
FSConstants.QUOTA_DONT_SET);
break;
}
case OP_CLEAR_NS_QUOTA: {
if (logVersion > -16) {
throw new IOException("Unexpected opcode " + opcode
+ " for version " + logVersion);
}
fsDir.unprotectedSetQuota(FSImage.readString(in),
FSConstants.QUOTA_RESET,
FSConstants.QUOTA_DONT_SET);
break;
}
case OP_SET_QUOTA:
fsDir.unprotectedSetQuota(FSImage.readString(in),
readLongWritable(in),
readLongWritable(in));
break;
case OP_TIMES: {
numOpTimes++;
int length = in.readInt();
if (length != 3) {
throw new IOException("Incorrect data format. "
+ "times operation.");
}
path = FSImage.readString(in);
mtime = readLong(in);
atime = readLong(in);
fsDir.unprotectedSetTimes(path, mtime, atime, true);
break;
}
default: {
throw new IOException("Never seen opcode " + opcode);
}
}
}
} finally {
in.close();
}
FSImage.LOG.info("Edits file " + edits.getName()
+ " of size " + edits.length() + " edits # " + numEdits
+ " loaded in " + (FSNamesystem.now()-startTime)/1000 + " seconds.");
if (FSImage.LOG.isDebugEnabled()) {
FSImage.LOG.debug("numOpAdd = " + numOpAdd + " numOpClose = " + numOpClose
+ " numOpDelete = " + numOpDelete + " numOpRename = " + numOpRename
+ " numOpSetRepl = " + numOpSetRepl + " numOpMkDir = " + numOpMkDir
+ " numOpSetPerm = " + numOpSetPerm
+ " numOpSetOwner = " + numOpSetOwner
+ " numOpSetGenStamp = " + numOpSetGenStamp
+ " numOpTimes = " + numOpTimes
+ " numOpOther = " + numOpOther);
}
if (logVersion != FSConstants.LAYOUT_VERSION) // other version
numEdits++; // save this image asap
return numEdits;
}
// a place holder for reading a long
private static final LongWritable longWritable = new LongWritable();
/** Read an integer from an input stream */
private static long readLongWritable(DataInputStream in) throws IOException {
synchronized (longWritable) {
longWritable.readFields(in);
return longWritable.get();
}
}
static short adjustReplication(short replication) {
FSNamesystem fsNamesys = FSNamesystem.getFSNamesystem();
short minReplication = fsNamesys.getMinReplication();
if (replication<minReplication) {
replication = minReplication;
}
short maxReplication = fsNamesys.getMaxReplication();
if (replication>maxReplication) {
replication = maxReplication;
}
return replication;
}
/**
* Write an operation to the edit log. Do not sync to persistent
* store yet.
*/
synchronized void logEdit(byte op, Writable ... writables) {
assert this.getNumEditStreams() > 0 : "no editlog streams";
long start = FSNamesystem.now();
for (int idx = 0; idx < editStreams.size(); idx++) {
EditLogOutputStream eStream = editStreams.get(idx);
try {
eStream.write(op, writables);
} catch (IOException ie) {
processIOError(idx);
// processIOError will remove the idx's stream
// from the editStreams collection, so we need to update idx
idx--;
}
}
// get a new transactionId
txid++;
//
// record the transactionId when new data was written to the edits log
//
TransactionId id = myTransactionId.get();
id.txid = txid;
// update statistics
long end = FSNamesystem.now();
numTransactions++;
totalTimeTransactions += (end-start);
if (metrics != null) // Metrics is non-null only when used inside name node
metrics.transactions.inc((end-start));
}
//
// Sync all modifications done by this thread.
//
public void logSync() throws IOException {
ArrayList<EditLogOutputStream> errorStreams = null;
long syncStart = 0;
// Fetch the transactionId of this thread.
long mytxid = myTransactionId.get().txid;
final int numEditStreams;
synchronized (this) {
numEditStreams = editStreams.size();
assert numEditStreams > 0 : "no editlog streams";
printStatistics(false);
// if somebody is already syncing, then wait
while (mytxid > synctxid && isSyncRunning) {
try {
wait(1000);
} catch (InterruptedException ie) {
}
}
//
// If this transaction was already flushed, then nothing to do
//
if (mytxid <= synctxid) {
numTransactionsBatchedInSync++;
if (metrics != null) // Metrics is non-null only when used inside name node
metrics.transactionsBatchedInSync.inc();
return;
}
// now, this thread will do the sync
syncStart = txid;
isSyncRunning = true;
// swap buffers
for (int idx = 0; idx < numEditStreams; idx++) {
editStreams.get(idx).setReadyToFlush();
}
}
// do the sync
long start = FSNamesystem.now();
for (int idx = 0; idx < numEditStreams; idx++) {
EditLogOutputStream eStream = editStreams.get(idx);
try {
eStream.flush();
} catch (IOException ie) {
//
// remember the streams that encountered an error.
//
if (errorStreams == null) {
errorStreams = new ArrayList<EditLogOutputStream>(1);
}
errorStreams.add(eStream);
FSNamesystem.LOG.error("Unable to sync edit log. " +
"Fatal Error.");
}
}
long elapsed = FSNamesystem.now() - start;
synchronized (this) {
processIOError(errorStreams);
synctxid = syncStart;
isSyncRunning = false;
this.notifyAll();
}
if (metrics != null) // Metrics is non-null only when used inside name node
metrics.syncs.inc(elapsed);
}
//
// print statistics every 1 minute.
//
private void printStatistics(boolean force) {
long now = FSNamesystem.now();
if (lastPrintTime + 60000 > now && !force) {
return;
}
if (editStreams == null || editStreams.size()==0) {
return;
}
lastPrintTime = now;
StringBuilder buf = new StringBuilder();
buf.append("Number of transactions: ");
buf.append(numTransactions);
buf.append(" Total time for transactions(ms): ");
buf.append(totalTimeTransactions);
buf.append("Number of transactions batched in Syncs: ");
buf.append(numTransactionsBatchedInSync);
buf.append(" Number of syncs: ");
buf.append(editStreams.get(0).getNumSync());
buf.append(" SyncTimes(ms): ");
int numEditStreams = editStreams.size();
for (int idx = 0; idx < numEditStreams; idx++) {
EditLogOutputStream eStream = editStreams.get(idx);
buf.append(eStream.getTotalSyncTime());
buf.append(" ");
}
FSNamesystem.LOG.info(buf);
}
/**
* Add open lease record to edit log.
* Records the block locations of the last block.
*/
public void logOpenFile(String path, INodeFileUnderConstruction newNode)
throws IOException {
UTF8 nameReplicationPair[] = new UTF8[] {
new UTF8(path),
FSEditLog.toLogReplication(newNode.getReplication()),
FSEditLog.toLogLong(newNode.getModificationTime()),
FSEditLog.toLogLong(newNode.getAccessTime()),
FSEditLog.toLogLong(newNode.getPreferredBlockSize())};
logEdit(OP_ADD,
new ArrayWritable(UTF8.class, nameReplicationPair),
new ArrayWritable(Block.class, newNode.getBlocks()),
newNode.getPermissionStatus(),
new UTF8(newNode.getClientName()),
new UTF8(newNode.getClientMachine()));
}
/**
* Add close lease record to edit log.
*/
public void logCloseFile(String path, INodeFile newNode) {
UTF8 nameReplicationPair[] = new UTF8[] {
new UTF8(path),
FSEditLog.toLogReplication(newNode.getReplication()),
FSEditLog.toLogLong(newNode.getModificationTime()),
FSEditLog.toLogLong(newNode.getAccessTime()),
FSEditLog.toLogLong(newNode.getPreferredBlockSize())};
logEdit(OP_CLOSE,
new ArrayWritable(UTF8.class, nameReplicationPair),
new ArrayWritable(Block.class, newNode.getBlocks()),
newNode.getPermissionStatus());
}
/**
* Add create directory record to edit log
*/
public void logMkDir(String path, INode newNode) {
UTF8 info[] = new UTF8[] {
new UTF8(path),
FSEditLog.toLogLong(newNode.getModificationTime()),
FSEditLog.toLogLong(newNode.getAccessTime())
};
logEdit(OP_MKDIR, new ArrayWritable(UTF8.class, info),
newNode.getPermissionStatus());
}
/**
* Add rename record to edit log
* TODO: use String parameters until just before writing to disk
*/
void logRename(String src, String dst, long timestamp) {
UTF8 info[] = new UTF8[] {
new UTF8(src),
new UTF8(dst),
FSEditLog.toLogLong(timestamp)};
logEdit(OP_RENAME, new ArrayWritable(UTF8.class, info));
}
/**
* Add set replication record to edit log
*/
void logSetReplication(String src, short replication) {
logEdit(OP_SET_REPLICATION,
new UTF8(src),
FSEditLog.toLogReplication(replication));
}
/** Add set namespace quota record to edit log
*
* @param src the string representation of the path to a directory
* @param quota the directory size limit
*/
void logSetQuota(String src, long nsQuota, long dsQuota) {
logEdit(OP_SET_QUOTA, new UTF8(src),
new LongWritable(nsQuota), new LongWritable(dsQuota));
}
/** Add set permissions record to edit log */
void logSetPermissions(String src, FsPermission permissions) {
logEdit(OP_SET_PERMISSIONS, new UTF8(src), permissions);
}
/** Add set owner record to edit log */
void logSetOwner(String src, String username, String groupname) {
UTF8 u = new UTF8(username == null? "": username);
UTF8 g = new UTF8(groupname == null? "": groupname);
logEdit(OP_SET_OWNER, new UTF8(src), u, g);
}
/**
* Add delete file record to edit log
*/
void logDelete(String src, long timestamp) {
UTF8 info[] = new UTF8[] {
new UTF8(src),
FSEditLog.toLogLong(timestamp)};
logEdit(OP_DELETE, new ArrayWritable(UTF8.class, info));
}
/**
* Add generation stamp record to edit log
*/
void logGenerationStamp(long genstamp) {
logEdit(OP_SET_GENSTAMP, new LongWritable(genstamp));
}
/**
* Add access time record to edit log
*/
void logTimes(String src, long mtime, long atime) {
UTF8 info[] = new UTF8[] {
new UTF8(src),
FSEditLog.toLogLong(mtime),
FSEditLog.toLogLong(atime)};
logEdit(OP_TIMES, new ArrayWritable(UTF8.class, info));
}
static private UTF8 toLogReplication(short replication) {
return new UTF8(Short.toString(replication));
}
static private UTF8 toLogLong(long timestamp) {
return new UTF8(Long.toString(timestamp));
}
/**
* Return the size of the current EditLog
*/
synchronized long getEditLogSize() throws IOException {
assert(getNumStorageDirs() == editStreams.size());
long size = 0;
for (int idx = 0; idx < editStreams.size(); idx++) {
long curSize = editStreams.get(idx).length();
assert (size == 0 || size == curSize) : "All streams must be the same";
size = curSize;
}
return size;
}
/**
* Closes the current edit log and opens edits.new.
* Returns the lastModified time of the edits log.
*/
synchronized void rollEditLog() throws IOException {
//
// If edits.new already exists in some directory, verify it
// exists in all directories.
//
if (existsNew()) {
for (Iterator<StorageDirectory> it =
fsimage.dirIterator(NameNodeDirType.EDITS); it.hasNext();) {
File editsNew = getEditNewFile(it.next());
if (!editsNew.exists()) {
throw new IOException("Inconsistent existance of edits.new " +
editsNew);
}
}
return; // nothing to do, edits.new exists!
}
close(); // close existing edit log
//
// Open edits.new
//
for (Iterator<StorageDirectory> it =
fsimage.dirIterator(NameNodeDirType.EDITS); it.hasNext();) {
StorageDirectory sd = it.next();
try {
EditLogFileOutputStream eStream =
new EditLogFileOutputStream(getEditNewFile(sd));
eStream.create();
editStreams.add(eStream);
} catch (IOException e) {
// remove stream and this storage directory from list
processIOError(sd);
it.remove();
}
}
}
/**
* Removes the old edit log and renamed edits.new as edits.
* Reopens the edits file.
*/
synchronized void purgeEditLog() throws IOException {
//
// If edits.new does not exists, then return error.
//
if (!existsNew()) {
throw new IOException("Attempt to purge edit log " +
"but edits.new does not exist.");
}
close();
//
// Delete edits and rename edits.new to edits.
//
for (Iterator<StorageDirectory> it =
fsimage.dirIterator(NameNodeDirType.EDITS); it.hasNext();) {
StorageDirectory sd = it.next();
if (!getEditNewFile(sd).renameTo(getEditFile(sd))) {
//
// renameTo() fails on Windows if the destination
// file exists.
//
getEditFile(sd).delete();
if (!getEditNewFile(sd).renameTo(getEditFile(sd))) {
// Should we also remove from edits
it.remove();
}
}
}
//
// Reopen all the edits logs.
//
open();
}
/**
* Return the name of the edit file
*/
synchronized File getFsEditName() throws IOException {
StorageDirectory sd = null;
for (Iterator<StorageDirectory> it =
fsimage.dirIterator(NameNodeDirType.EDITS); it.hasNext();)
sd = it.next();
return getEditFile(sd);
}
/**
* Returns the timestamp of the edit log
*/
synchronized long getFsEditTime() {
Iterator<StorageDirectory> it = fsimage.dirIterator(NameNodeDirType.EDITS);
if(it.hasNext())
return getEditFile(it.next()).lastModified();
return 0;
}
// sets the initial capacity of the flush buffer.
static void setBufferCapacity(int size) {
sizeFlushBuffer = size;
}
/**
* A class to read in blocks stored in the old format. The only two
* fields in the block were blockid and length.
*/
static class BlockTwo implements Writable {
long blkid;
long len;
static { // register a ctor
WritableFactories.setFactory
(BlockTwo.class,
new WritableFactory() {
public Writable newInstance() { return new BlockTwo(); }
});
}
BlockTwo() {
blkid = 0;
len = 0;
}
/////////////////////////////////////
// Writable
/////////////////////////////////////
public void write(DataOutput out) throws IOException {
out.writeLong(blkid);
out.writeLong(len);
}
public void readFields(DataInput in) throws IOException {
this.blkid = in.readLong();
this.len = in.readLong();
}
}
/** This method is defined for compatibility reason. */
static private DatanodeDescriptor[] readDatanodeDescriptorArray(DataInput in
) throws IOException {
DatanodeDescriptor[] locations = new DatanodeDescriptor[in.readInt()];
for (int i = 0; i < locations.length; i++) {
locations[i] = new DatanodeDescriptor();
locations[i].readFieldsFromFSEditLog(in);
}
return locations;
}
static private short readShort(DataInputStream in) throws IOException {
return Short.parseShort(FSImage.readString(in));
}
static private long readLong(DataInputStream in) throws IOException {
return Long.parseLong(FSImage.readString(in));
}
static private Block[] readBlocks(DataInputStream in) throws IOException {
int numBlocks = in.readInt();
Block[] blocks = new Block[numBlocks];
for (int i = 0; i < numBlocks; i++) {
blocks[i] = new Block();
blocks[i].readFields(in);
}
return blocks;
}
}