org.apache.hadoop.hdfs.qjournal.server
Class Journal

java.lang.Object
  org.apache.hadoop.hdfs.qjournal.server.Journal

All Implemented Interfaces:

Closeable

public class Journal
extends Object
implements Closeable

A JournalNode can manage journals for several clusters at once. Each such journal is entirely independent despite being hosted by the same JVM.

Field Summary

static String	LAST_PROMISED_FILENAME
static String	LAST_WRITER_EPOCH

Method Summary

void	acceptRecovery(org.apache.hadoop.hdfs.qjournal.protocol.RequestInfo reqInfo, QJournalProtocolProtos.SegmentStateProto segment, URL fromUrl)
Boolean	canRollBack(org.apache.hadoop.hdfs.server.common.StorageInfo storage, org.apache.hadoop.hdfs.server.common.StorageInfo prevStorage, int targetLayoutVersion)
void	close() Unlock and release resources.
void	doFinalize()
void	doPreUpgrade()
void	doRollback()
void	doUpgrade(org.apache.hadoop.hdfs.server.common.StorageInfo sInfo)
void	finalizeLogSegment(org.apache.hadoop.hdfs.qjournal.protocol.RequestInfo reqInfo, long startTxId, long endTxId) Finalize the log segment at the given transaction ID.
RemoteEditLogManifest	getEditLogManifest(long sinceTxId, boolean inProgressOk)
Long	getJournalCTime()
long	getLastWriterEpoch()
void	heartbeat(org.apache.hadoop.hdfs.qjournal.protocol.RequestInfo reqInfo)
boolean	isFormatted()
QJournalProtocolProtos.PrepareRecoveryResponseProto	prepareRecovery(org.apache.hadoop.hdfs.qjournal.protocol.RequestInfo reqInfo, long segmentTxId)
void	purgeLogsOlderThan(org.apache.hadoop.hdfs.qjournal.protocol.RequestInfo reqInfo, long minTxIdToKeep)
void	startLogSegment(org.apache.hadoop.hdfs.qjournal.protocol.RequestInfo reqInfo, long txid, int layoutVersion) Start a new segment at the given txid.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

LAST_PROMISED_FILENAME

public static final String LAST_PROMISED_FILENAME

See Also:

Constant Field Values

LAST_WRITER_EPOCH

public static final String LAST_WRITER_EPOCH

See Also:

Constant Field Values

Method Detail

close

public void close()
           throws IOException

Unlock and release resources.

Specified by:

close in interface Closeable

Throws:

IOException

getLastWriterEpoch

public long getLastWriterEpoch()
                        throws IOException

Throws:

IOException

heartbeat

public void heartbeat(org.apache.hadoop.hdfs.qjournal.protocol.RequestInfo reqInfo)
               throws IOException

Throws:

IOException

isFormatted

public boolean isFormatted()

startLogSegment

public void startLogSegment(org.apache.hadoop.hdfs.qjournal.protocol.RequestInfo reqInfo,
                            long txid,
                            int layoutVersion)
                     throws IOException

Start a new segment at the given txid. The previous segment must have already been finalized.

Throws:

IOException

finalizeLogSegment

public void finalizeLogSegment(org.apache.hadoop.hdfs.qjournal.protocol.RequestInfo reqInfo,
                               long startTxId,
                               long endTxId)
                        throws IOException

Finalize the log segment at the given transaction ID.

Throws:

IOException

purgeLogsOlderThan

public void purgeLogsOlderThan(org.apache.hadoop.hdfs.qjournal.protocol.RequestInfo reqInfo,
                               long minTxIdToKeep)
                        throws IOException

Throws:

IOException

See Also:

LogsPurgeable.purgeLogsOlderThan(long)

getEditLogManifest

public RemoteEditLogManifest getEditLogManifest(long sinceTxId,
                                                boolean inProgressOk)
                                         throws IOException

Throws:

IOException

See Also:

QJournalProtocol.getEditLogManifest(String, long, boolean)

prepareRecovery

public QJournalProtocolProtos.PrepareRecoveryResponseProto prepareRecovery(org.apache.hadoop.hdfs.qjournal.protocol.RequestInfo reqInfo,
                                                                           long segmentTxId)
                                                                    throws IOException

Throws:

IOException

See Also:

QJournalProtocol.prepareRecovery(RequestInfo, long)

acceptRecovery

public void acceptRecovery(org.apache.hadoop.hdfs.qjournal.protocol.RequestInfo reqInfo,
                           QJournalProtocolProtos.SegmentStateProto segment,
                           URL fromUrl)
                    throws IOException

Throws:

IOException

See Also:

QJournalProtocol.acceptRecovery(RequestInfo, QJournalProtocolProtos.SegmentStateProto, URL)

doPreUpgrade

public void doPreUpgrade()
                  throws IOException

Throws:

IOException

doUpgrade

public void doUpgrade(org.apache.hadoop.hdfs.server.common.StorageInfo sInfo)
               throws IOException

Throws:

IOException

doFinalize

public void doFinalize()
                throws IOException

Throws:

IOException

canRollBack

public Boolean canRollBack(org.apache.hadoop.hdfs.server.common.StorageInfo storage,
                           org.apache.hadoop.hdfs.server.common.StorageInfo prevStorage,
                           int targetLayoutVersion)
                    throws IOException

Throws:

IOException

doRollback

public void doRollback()
                throws IOException

Throws:

IOException

getJournalCTime

public Long getJournalCTime()
                     throws IOException

Throws:

IOException