/**
* 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.contrib.bkjournal;
import org.apache.hadoop.hdfs.protocol.HdfsConstants;
import org.apache.hadoop.hdfs.server.namenode.JournalManager;
import org.apache.hadoop.hdfs.server.namenode.EditLogOutputStream;
import org.apache.hadoop.hdfs.server.namenode.EditLogInputStream;
import org.apache.hadoop.hdfs.server.namenode.FSEditLogOp;
import org.apache.hadoop.hdfs.server.protocol.NamespaceInfo;
import org.apache.hadoop.conf.Configuration;
import org.apache.bookkeeper.conf.ClientConfiguration;
import org.apache.bookkeeper.client.BKException;
import org.apache.bookkeeper.client.BookKeeper;
import org.apache.bookkeeper.client.LedgerHandle;
import org.apache.bookkeeper.util.ZkUtils;
import org.apache.zookeeper.data.Stat;
import org.apache.zookeeper.ZooKeeper;
import org.apache.zookeeper.Watcher;
import org.apache.zookeeper.WatchedEvent;
import org.apache.zookeeper.KeeperException;
import org.apache.zookeeper.CreateMode;
import org.apache.zookeeper.ZooDefs.Ids;
import org.apache.zookeeper.AsyncCallback.StringCallback;
import org.apache.zookeeper.ZKUtil;
import java.util.Collection;
import java.util.Collections;
import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.atomic.AtomicBoolean;
import java.io.IOException;
import java.net.URI;
import org.apache.hadoop.hdfs.protocolPB.PBHelper;
import org.apache.hadoop.contrib.bkjournal.BKJournalProtos.VersionProto;
import com.google.protobuf.TextFormat;
import static com.google.common.base.Charsets.UTF_8;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import com.google.common.annotations.VisibleForTesting;
/**
* BookKeeper Journal Manager
*
* To use, add the following to hdfs-site.xml.
* <pre>
* {@code
* <property>
* <name>dfs.namenode.edits.dir</name>
* <value>bookkeeper://zk1:2181;zk2:2181;zk3:2181/hdfsjournal</value>
* </property>
*
* <property>
* <name>dfs.namenode.edits.journal-plugin.bookkeeper</name>
* <value>org.apache.hadoop.contrib.bkjournal.BookKeeperJournalManager</value>
* </property>
* }
* </pre>
* The URI format for bookkeeper is bookkeeper://[zkEnsemble]/[rootZnode]
* [zookkeeper ensemble] is a list of semi-colon separated, zookeeper host:port
* pairs. In the example above there are 3 servers, in the ensemble,
* zk1, zk2 & zk3, each one listening on port 2181.
*
* [root znode] is the path of the zookeeper znode, under which the editlog
* information will be stored.
*
* Other configuration options are:
* <ul>
* <li><b>dfs.namenode.bookkeeperjournal.output-buffer-size</b>
* Number of bytes a bookkeeper journal stream will buffer before
* forcing a flush. Default is 1024.</li>
* <li><b>dfs.namenode.bookkeeperjournal.ensemble-size</b>
* Number of bookkeeper servers in edit log ledger ensembles. This
* is the number of bookkeeper servers which need to be available
* for the ledger to be writable. Default is 3.</li>
* <li><b>dfs.namenode.bookkeeperjournal.quorum-size</b>
* Number of bookkeeper servers in the write quorum. This is the
* number of bookkeeper servers which must have acknowledged the
* write of an entry before it is considered written.
* Default is 2.</li>
* <li><b>dfs.namenode.bookkeeperjournal.digestPw</b>
* Password to use when creating ledgers. </li>
* <li><b>dfs.namenode.bookkeeperjournal.zk.session.timeout</b>
* Session timeout for Zookeeper client from BookKeeper Journal Manager.
* Hadoop recommends that, this value should be less than the ZKFC
* session timeout value. Default value is 3000.</li>
* </ul>
*/
public class BookKeeperJournalManager implements JournalManager {
static final Log LOG = LogFactory.getLog(BookKeeperJournalManager.class);
public static final String BKJM_OUTPUT_BUFFER_SIZE
= "dfs.namenode.bookkeeperjournal.output-buffer-size";
public static final int BKJM_OUTPUT_BUFFER_SIZE_DEFAULT = 1024;
public static final String BKJM_BOOKKEEPER_ENSEMBLE_SIZE
= "dfs.namenode.bookkeeperjournal.ensemble-size";
public static final int BKJM_BOOKKEEPER_ENSEMBLE_SIZE_DEFAULT = 3;
public static final String BKJM_BOOKKEEPER_QUORUM_SIZE
= "dfs.namenode.bookkeeperjournal.quorum-size";
public static final int BKJM_BOOKKEEPER_QUORUM_SIZE_DEFAULT = 2;
public static final String BKJM_BOOKKEEPER_DIGEST_PW
= "dfs.namenode.bookkeeperjournal.digestPw";
public static final String BKJM_BOOKKEEPER_DIGEST_PW_DEFAULT = "";
private static final int BKJM_LAYOUT_VERSION = -1;
public static final String BKJM_ZK_SESSION_TIMEOUT
= "dfs.namenode.bookkeeperjournal.zk.session.timeout";
public static final int BKJM_ZK_SESSION_TIMEOUT_DEFAULT = 3000;
private static final String BKJM_EDIT_INPROGRESS = "inprogress_";
public static final String BKJM_ZK_LEDGERS_AVAILABLE_PATH
= "dfs.namenode.bookkeeperjournal.zk.availablebookies";
public static final String BKJM_ZK_LEDGERS_AVAILABLE_PATH_DEFAULT
= "/ledgers/available";
private ZooKeeper zkc;
private final Configuration conf;
private final BookKeeper bkc;
private final CurrentInprogress ci;
private final String basePath;
private final String ledgerPath;
private final String versionPath;
private final MaxTxId maxTxId;
private final int ensembleSize;
private final int quorumSize;
private final String digestpw;
private final CountDownLatch zkConnectLatch;
private final NamespaceInfo nsInfo;
private boolean initialized = false;
private LedgerHandle currentLedger = null;
/**
* Construct a Bookkeeper journal manager.
*/
public BookKeeperJournalManager(Configuration conf, URI uri,
NamespaceInfo nsInfo) throws IOException {
this.conf = conf;
this.nsInfo = nsInfo;
String zkConnect = uri.getAuthority().replace(";", ",");
basePath = uri.getPath();
ensembleSize = conf.getInt(BKJM_BOOKKEEPER_ENSEMBLE_SIZE,
BKJM_BOOKKEEPER_ENSEMBLE_SIZE_DEFAULT);
quorumSize = conf.getInt(BKJM_BOOKKEEPER_QUORUM_SIZE,
BKJM_BOOKKEEPER_QUORUM_SIZE_DEFAULT);
ledgerPath = basePath + "/ledgers";
String maxTxIdPath = basePath + "/maxtxid";
String currentInprogressNodePath = basePath + "/CurrentInprogress";
versionPath = basePath + "/version";
digestpw = conf.get(BKJM_BOOKKEEPER_DIGEST_PW,
BKJM_BOOKKEEPER_DIGEST_PW_DEFAULT);
try {
zkConnectLatch = new CountDownLatch(1);
int bkjmZKSessionTimeout = conf.getInt(BKJM_ZK_SESSION_TIMEOUT,
BKJM_ZK_SESSION_TIMEOUT_DEFAULT);
zkc = new ZooKeeper(zkConnect, bkjmZKSessionTimeout,
new ZkConnectionWatcher());
// Configured zk session timeout + some extra grace period (here
// BKJM_ZK_SESSION_TIMEOUT_DEFAULT used as grace period)
int zkConnectionLatchTimeout = bkjmZKSessionTimeout
+ BKJM_ZK_SESSION_TIMEOUT_DEFAULT;
if (!zkConnectLatch
.await(zkConnectionLatchTimeout, TimeUnit.MILLISECONDS)) {
throw new IOException("Error connecting to zookeeper");
}
prepareBookKeeperEnv();
bkc = new BookKeeper(new ClientConfiguration(), zkc);
} catch (KeeperException e) {
throw new IOException("Error initializing zk", e);
} catch (InterruptedException ie) {
Thread.currentThread().interrupt();
throw new IOException("Interrupted while initializing bk journal manager",
ie);
}
ci = new CurrentInprogress(zkc, currentInprogressNodePath);
maxTxId = new MaxTxId(zkc, maxTxIdPath);
}
/**
* Pre-creating bookkeeper metadata path in zookeeper.
*/
private void prepareBookKeeperEnv() throws IOException {
// create bookie available path in zookeeper if it doesn't exists
final String zkAvailablePath = conf.get(BKJM_ZK_LEDGERS_AVAILABLE_PATH,
BKJM_ZK_LEDGERS_AVAILABLE_PATH_DEFAULT);
final CountDownLatch zkPathLatch = new CountDownLatch(1);
final AtomicBoolean success = new AtomicBoolean(false);
StringCallback callback = new StringCallback() {
@Override
public void processResult(int rc, String path, Object ctx, String name) {
if (KeeperException.Code.OK.intValue() == rc
|| KeeperException.Code.NODEEXISTS.intValue() == rc) {
LOG.info("Successfully created bookie available path : "
+ zkAvailablePath);
success.set(true);
} else {
KeeperException.Code code = KeeperException.Code.get(rc);
LOG.error("Error : "
+ KeeperException.create(code, path).getMessage()
+ ", failed to create bookie available path : "
+ zkAvailablePath);
}
zkPathLatch.countDown();
}
};
ZkUtils.createFullPathOptimistic(zkc, zkAvailablePath, new byte[0],
Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT, callback, null);
try {
if (!zkPathLatch.await(zkc.getSessionTimeout(), TimeUnit.MILLISECONDS)
|| !success.get()) {
throw new IOException("Couldn't create bookie available path :"
+ zkAvailablePath + ", timed out " + zkc.getSessionTimeout()
+ " millis");
}
} catch (InterruptedException e) {
Thread.currentThread().interrupt();
throw new IOException(
"Interrupted when creating the bookie available path : "
+ zkAvailablePath, e);
}
}
@Override
public void format(NamespaceInfo ns) throws IOException {
try {
// delete old info
Stat baseStat = null;
Stat ledgerStat = null;
if ((baseStat = zkc.exists(basePath, false)) != null) {
if ((ledgerStat = zkc.exists(ledgerPath, false)) != null) {
for (EditLogLedgerMetadata l : getLedgerList(true)) {
try {
bkc.deleteLedger(l.getLedgerId());
} catch (BKException.BKNoSuchLedgerExistsException bke) {
LOG.warn("Ledger " + l.getLedgerId() + " does not exist;"
+ " Cannot delete.");
}
}
}
ZKUtil.deleteRecursive(zkc, basePath);
}
// should be clean now.
zkc.create(basePath, new byte[] {'0'},
Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);
VersionProto.Builder builder = VersionProto.newBuilder();
builder.setNamespaceInfo(PBHelper.convert(ns))
.setLayoutVersion(BKJM_LAYOUT_VERSION);
byte[] data = TextFormat.printToString(builder.build()).getBytes(UTF_8);
zkc.create(versionPath, data,
Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);
zkc.create(ledgerPath, new byte[] {'0'},
Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);
} catch (KeeperException ke) {
LOG.error("Error accessing zookeeper to format", ke);
throw new IOException("Error accessing zookeeper to format", ke);
} catch (InterruptedException ie) {
Thread.currentThread().interrupt();
throw new IOException("Interrupted during format", ie);
} catch (BKException bke) {
throw new IOException("Error cleaning up ledgers during format", bke);
}
}
@Override
public boolean hasSomeData() throws IOException {
try {
return zkc.exists(basePath, false) != null;
} catch (KeeperException ke) {
throw new IOException("Couldn't contact zookeeper", ke);
} catch (InterruptedException ie) {
Thread.currentThread().interrupt();
throw new IOException("Interrupted while checking for data", ie);
}
}
synchronized private void checkEnv() throws IOException {
if (!initialized) {
try {
Stat versionStat = zkc.exists(versionPath, false);
if (versionStat == null) {
throw new IOException("Environment not initialized. "
+"Have you forgotten to format?");
}
byte[] d = zkc.getData(versionPath, false, versionStat);
VersionProto.Builder builder = VersionProto.newBuilder();
TextFormat.merge(new String(d, UTF_8), builder);
if (!builder.isInitialized()) {
throw new IOException("Invalid/Incomplete data in znode");
}
VersionProto vp = builder.build();
// There's only one version at the moment
assert vp.getLayoutVersion() == BKJM_LAYOUT_VERSION;
NamespaceInfo readns = PBHelper.convert(vp.getNamespaceInfo());
if (nsInfo.getNamespaceID() != readns.getNamespaceID() ||
!nsInfo.clusterID.equals(readns.getClusterID()) ||
!nsInfo.getBlockPoolID().equals(readns.getBlockPoolID())) {
String err = String.format("Environment mismatch. Running process %s"
+", stored in ZK %s", nsInfo, readns);
LOG.error(err);
throw new IOException(err);
}
ci.init();
initialized = true;
} catch (KeeperException ke) {
throw new IOException("Cannot access ZooKeeper", ke);
} catch (InterruptedException ie) {
Thread.currentThread().interrupt();
throw new IOException("Interrupted while checking environment", ie);
}
}
}
/**
* Start a new log segment in a BookKeeper ledger.
* First ensure that we have the write lock for this journal.
* Then create a ledger and stream based on that ledger.
* The ledger id is written to the inprogress znode, so that in the
* case of a crash, a recovery process can find the ledger we were writing
* to when we crashed.
* @param txId First transaction id to be written to the stream
*/
@Override
public EditLogOutputStream startLogSegment(long txId) throws IOException {
checkEnv();
if (txId <= maxTxId.get()) {
throw new IOException("We've already seen " + txId
+ ". A new stream cannot be created with it");
}
try {
String existingInprogressNode = ci.read();
if (null != existingInprogressNode
&& zkc.exists(existingInprogressNode, false) != null) {
throw new IOException("Inprogress node already exists");
}
if (currentLedger != null) {
// bookkeeper errored on last stream, clean up ledger
currentLedger.close();
}
currentLedger = bkc.createLedger(ensembleSize, quorumSize,
BookKeeper.DigestType.MAC,
digestpw.getBytes());
} catch (BKException bke) {
throw new IOException("Error creating ledger", bke);
} catch (KeeperException ke) {
throw new IOException("Error in zookeeper while creating ledger", ke);
} catch (InterruptedException ie) {
Thread.currentThread().interrupt();
throw new IOException("Interrupted creating ledger", ie);
}
try {
String znodePath = inprogressZNode(txId);
EditLogLedgerMetadata l = new EditLogLedgerMetadata(znodePath,
HdfsConstants.LAYOUT_VERSION, currentLedger.getId(), txId);
/* Write the ledger metadata out to the inprogress ledger znode
* This can fail if for some reason our write lock has
* expired (@see WriteLock) and another process has managed to
* create the inprogress znode.
* In this case, throw an exception. We don't want to continue
* as this would lead to a split brain situation.
*/
l.write(zkc, znodePath);
maxTxId.store(txId);
ci.update(znodePath);
return new BookKeeperEditLogOutputStream(conf, currentLedger);
} catch (KeeperException ke) {
cleanupLedger(currentLedger);
throw new IOException("Error storing ledger metadata", ke);
}
}
private void cleanupLedger(LedgerHandle lh) {
try {
long id = currentLedger.getId();
currentLedger.close();
bkc.deleteLedger(id);
} catch (BKException bke) {
//log & ignore, an IOException will be thrown soon
LOG.error("Error closing ledger", bke);
} catch (InterruptedException ie) {
Thread.currentThread().interrupt();
LOG.warn("Interrupted while closing ledger", ie);
}
}
/**
* Finalize a log segment. If the journal manager is currently
* writing to a ledger, ensure that this is the ledger of the log segment
* being finalized.
*
* Otherwise this is the recovery case. In the recovery case, ensure that
* the firstTxId of the ledger matches firstTxId for the segment we are
* trying to finalize.
*/
@Override
public void finalizeLogSegment(long firstTxId, long lastTxId)
throws IOException {
checkEnv();
String inprogressPath = inprogressZNode(firstTxId);
try {
Stat inprogressStat = zkc.exists(inprogressPath, false);
if (inprogressStat == null) {
throw new IOException("Inprogress znode " + inprogressPath
+ " doesn't exist");
}
EditLogLedgerMetadata l
= EditLogLedgerMetadata.read(zkc, inprogressPath);
if (currentLedger != null) { // normal, non-recovery case
if (l.getLedgerId() == currentLedger.getId()) {
try {
currentLedger.close();
} catch (BKException bke) {
LOG.error("Error closing current ledger", bke);
}
currentLedger = null;
} else {
throw new IOException(
"Active ledger has different ID to inprogress. "
+ l.getLedgerId() + " found, "
+ currentLedger.getId() + " expected");
}
}
if (l.getFirstTxId() != firstTxId) {
throw new IOException("Transaction id not as expected, "
+ l.getFirstTxId() + " found, " + firstTxId + " expected");
}
l.finalizeLedger(lastTxId);
String finalisedPath = finalizedLedgerZNode(firstTxId, lastTxId);
try {
l.write(zkc, finalisedPath);
} catch (KeeperException.NodeExistsException nee) {
if (!l.verify(zkc, finalisedPath)) {
throw new IOException("Node " + finalisedPath + " already exists"
+ " but data doesn't match");
}
}
maxTxId.store(lastTxId);
zkc.delete(inprogressPath, inprogressStat.getVersion());
String inprogressPathFromCI = ci.read();
if (inprogressPath.equals(inprogressPathFromCI)) {
ci.clear();
}
} catch (KeeperException e) {
throw new IOException("Error finalising ledger", e);
} catch (InterruptedException ie) {
Thread.currentThread().interrupt();
throw new IOException("Error finalising ledger", ie);
}
}
public void selectInputStreams(Collection<EditLogInputStream> streams,
long fromTxId, boolean inProgressOk) throws IOException {
selectInputStreams(streams, fromTxId, inProgressOk, true);
}
@Override
public void selectInputStreams(Collection<EditLogInputStream> streams,
long fromTxId, boolean inProgressOk, boolean forReading)
throws IOException {
List<EditLogLedgerMetadata> currentLedgerList = getLedgerList(fromTxId,
inProgressOk);
try {
BookKeeperEditLogInputStream elis = null;
for (EditLogLedgerMetadata l : currentLedgerList) {
long lastTxId = l.getLastTxId();
if (l.isInProgress()) {
lastTxId = recoverLastTxId(l, false);
}
// Check once again, required in case of InProgress and is case of any
// gap.
if (fromTxId >= l.getFirstTxId() && fromTxId <= lastTxId) {
LedgerHandle h;
if (l.isInProgress()) { // we don't want to fence the current journal
h = bkc.openLedgerNoRecovery(l.getLedgerId(),
BookKeeper.DigestType.MAC, digestpw.getBytes());
} else {
h = bkc.openLedger(l.getLedgerId(), BookKeeper.DigestType.MAC,
digestpw.getBytes());
}
elis = new BookKeeperEditLogInputStream(h, l);
elis.skipTo(fromTxId);
} else {
// If mismatches then there might be some gap, so we should not check
// further.
return;
}
streams.add(elis);
if (elis.getLastTxId() == HdfsConstants.INVALID_TXID) {
return;
}
fromTxId = elis.getLastTxId() + 1;
}
} catch (BKException e) {
throw new IOException("Could not open ledger for " + fromTxId, e);
} catch (InterruptedException ie) {
Thread.currentThread().interrupt();
throw new IOException("Interrupted opening ledger for " + fromTxId, ie);
}
}
long getNumberOfTransactions(long fromTxId, boolean inProgressOk)
throws IOException {
long count = 0;
long expectedStart = 0;
for (EditLogLedgerMetadata l : getLedgerList(inProgressOk)) {
long lastTxId = l.getLastTxId();
if (l.isInProgress()) {
lastTxId = recoverLastTxId(l, false);
if (lastTxId == HdfsConstants.INVALID_TXID) {
break;
}
}
assert lastTxId >= l.getFirstTxId();
if (lastTxId < fromTxId) {
continue;
} else if (l.getFirstTxId() <= fromTxId && lastTxId >= fromTxId) {
// we can start in the middle of a segment
count = (lastTxId - l.getFirstTxId()) + 1;
expectedStart = lastTxId + 1;
} else {
if (expectedStart != l.getFirstTxId()) {
if (count == 0) {
throw new CorruptionException("StartTxId " + l.getFirstTxId()
+ " is not as expected " + expectedStart
+ ". Gap in transaction log?");
} else {
break;
}
}
count += (lastTxId - l.getFirstTxId()) + 1;
expectedStart = lastTxId + 1;
}
}
return count;
}
@Override
public void recoverUnfinalizedSegments() throws IOException {
checkEnv();
synchronized (this) {
try {
List<String> children = zkc.getChildren(ledgerPath, false);
for (String child : children) {
if (!child.startsWith(BKJM_EDIT_INPROGRESS)) {
continue;
}
String znode = ledgerPath + "/" + child;
EditLogLedgerMetadata l = EditLogLedgerMetadata.read(zkc, znode);
try {
long endTxId = recoverLastTxId(l, true);
if (endTxId == HdfsConstants.INVALID_TXID) {
LOG.error("Unrecoverable corruption has occurred in segment "
+ l.toString() + " at path " + znode
+ ". Unable to continue recovery.");
throw new IOException("Unrecoverable corruption,"
+ " please check logs.");
}
finalizeLogSegment(l.getFirstTxId(), endTxId);
} catch (SegmentEmptyException see) {
LOG.warn("Inprogress znode " + child
+ " refers to a ledger which is empty. This occurs when the NN"
+ " crashes after opening a segment, but before writing the"
+ " OP_START_LOG_SEGMENT op. It is safe to delete."
+ " MetaData [" + l.toString() + "]");
// If the max seen transaction is the same as what would
// have been the first transaction of the failed ledger,
// decrement it, as that transaction never happened and as
// such, is _not_ the last seen
if (maxTxId.get() == l.getFirstTxId()) {
maxTxId.reset(maxTxId.get() - 1);
}
zkc.delete(znode, -1);
}
}
} catch (KeeperException.NoNodeException nne) {
// nothing to recover, ignore
} catch (KeeperException ke) {
throw new IOException("Couldn't get list of inprogress segments", ke);
} catch (InterruptedException ie) {
Thread.currentThread().interrupt();
throw new IOException("Interrupted getting list of inprogress segments",
ie);
}
}
}
@Override
public void purgeLogsOlderThan(long minTxIdToKeep)
throws IOException {
checkEnv();
for (EditLogLedgerMetadata l : getLedgerList(false)) {
if (l.getLastTxId() < minTxIdToKeep) {
try {
Stat stat = zkc.exists(l.getZkPath(), false);
zkc.delete(l.getZkPath(), stat.getVersion());
bkc.deleteLedger(l.getLedgerId());
} catch (InterruptedException ie) {
Thread.currentThread().interrupt();
LOG.error("Interrupted while purging " + l, ie);
} catch (BKException bke) {
LOG.error("Couldn't delete ledger from bookkeeper", bke);
} catch (KeeperException ke) {
LOG.error("Error deleting ledger entry in zookeeper", ke);
}
}
}
}
@Override
public void close() throws IOException {
try {
bkc.close();
zkc.close();
} catch (BKException bke) {
throw new IOException("Couldn't close bookkeeper client", bke);
} catch (InterruptedException ie) {
Thread.currentThread().interrupt();
throw new IOException("Interrupted while closing journal manager", ie);
}
}
/**
* Set the amount of memory that this stream should use to buffer edits.
* Setting this will only affect future output stream. Streams
* which have currently be created won't be affected.
*/
@Override
public void setOutputBufferCapacity(int size) {
conf.getInt(BKJM_OUTPUT_BUFFER_SIZE, size);
}
/**
* Find the id of the last edit log transaction writen to a edit log
* ledger.
*/
private long recoverLastTxId(EditLogLedgerMetadata l, boolean fence)
throws IOException, SegmentEmptyException {
LedgerHandle lh = null;
try {
if (fence) {
lh = bkc.openLedger(l.getLedgerId(),
BookKeeper.DigestType.MAC,
digestpw.getBytes());
} else {
lh = bkc.openLedgerNoRecovery(l.getLedgerId(),
BookKeeper.DigestType.MAC,
digestpw.getBytes());
}
} catch (BKException bke) {
throw new IOException("Exception opening ledger for " + l, bke);
} catch (InterruptedException ie) {
Thread.currentThread().interrupt();
throw new IOException("Interrupted opening ledger for " + l, ie);
}
BookKeeperEditLogInputStream in = null;
try {
long lastAddConfirmed = lh.getLastAddConfirmed();
if (lastAddConfirmed == -1) {
throw new SegmentEmptyException();
}
in = new BookKeeperEditLogInputStream(lh, l, lastAddConfirmed);
long endTxId = HdfsConstants.INVALID_TXID;
FSEditLogOp op = in.readOp();
while (op != null) {
if (endTxId == HdfsConstants.INVALID_TXID
|| op.getTransactionId() == endTxId+1) {
endTxId = op.getTransactionId();
}
op = in.readOp();
}
return endTxId;
} finally {
if (in != null) {
in.close();
}
}
}
/**
* Get a list of all segments in the journal.
*/
List<EditLogLedgerMetadata> getLedgerList(boolean inProgressOk)
throws IOException {
return getLedgerList(-1, inProgressOk);
}
private List<EditLogLedgerMetadata> getLedgerList(long fromTxId,
boolean inProgressOk) throws IOException {
List<EditLogLedgerMetadata> ledgers
= new ArrayList<EditLogLedgerMetadata>();
try {
List<String> ledgerNames = zkc.getChildren(ledgerPath, false);
for (String ledgerName : ledgerNames) {
if (!inProgressOk && ledgerName.contains(BKJM_EDIT_INPROGRESS)) {
continue;
}
String legderMetadataPath = ledgerPath + "/" + ledgerName;
try {
EditLogLedgerMetadata editLogLedgerMetadata = EditLogLedgerMetadata
.read(zkc, legderMetadataPath);
if (editLogLedgerMetadata.getLastTxId() != HdfsConstants.INVALID_TXID
&& editLogLedgerMetadata.getLastTxId() < fromTxId) {
// exclude already read closed edits, but include inprogress edits
// as this will be handled in caller
continue;
}
ledgers.add(editLogLedgerMetadata);
} catch (KeeperException.NoNodeException e) {
LOG.warn("ZNode: " + legderMetadataPath
+ " might have finalized and deleted."
+ " So ignoring NoNodeException.");
}
}
} catch (KeeperException e) {
throw new IOException("Exception reading ledger list from zk", e);
} catch (InterruptedException ie) {
Thread.currentThread().interrupt();
throw new IOException("Interrupted getting list of ledgers from zk", ie);
}
Collections.sort(ledgers, EditLogLedgerMetadata.COMPARATOR);
return ledgers;
}
/**
* Get the znode path for a finalize ledger
*/
String finalizedLedgerZNode(long startTxId, long endTxId) {
return String.format("%s/edits_%018d_%018d",
ledgerPath, startTxId, endTxId);
}
/**
* Get the znode path for the inprogressZNode
*/
String inprogressZNode(long startTxid) {
return ledgerPath + "/inprogress_" + Long.toString(startTxid, 16);
}
@VisibleForTesting
void setZooKeeper(ZooKeeper zk) {
this.zkc = zk;
}
/**
* Simple watcher to notify when zookeeper has connected
*/
private class ZkConnectionWatcher implements Watcher {
public void process(WatchedEvent event) {
if (Event.KeeperState.SyncConnected.equals(event.getState())) {
zkConnectLatch.countDown();
}
}
}
private static class SegmentEmptyException extends IOException {
}
}