Examples with LogEntry org.neo4j.kernel.impl.transaction.log.entry.LogEntry used on opensource projects

Example 16 with LogEntry

use of org.neo4j.kernel.impl.transaction.log.entry.LogEntry in project neo4j by neo4j.

the class TransactionLogEntryCursorTest method mockedLogEntry.

private LogEntry mockedLogEntry(byte type) {
    LogEntry logEntry = mock(LogEntry.class);
    when(logEntry.getType()).thenReturn(type);
    return logEntry;
}

Example 17 with LogEntry

use of org.neo4j.kernel.impl.transaction.log.entry.LogEntry in project neo4j by neo4j.

the class LatestCheckPointFinder method find.

public LatestCheckPoint find(long fromVersionBackwards) throws IOException {
    long version = fromVersionBackwards;
    long versionToSearchForCommits = fromVersionBackwards;
    LogEntryStart latestStartEntry = null;
    LogEntryStart oldestStartEntry = null;
    long oldestVersionFound = -1;
    while (version >= INITIAL_LOG_VERSION) {
        LogVersionedStoreChannel channel = PhysicalLogFile.tryOpenForVersion(logFiles, fileSystem, version, false);
        if (channel == null) {
            break;
        }
        oldestVersionFound = version;
        CheckPoint latestCheckPoint = null;
        ReadableLogChannel recoveredDataChannel = new ReadAheadLogChannel(channel, NO_MORE_CHANNELS);
        boolean firstStartEntry = true;
        try (LogEntryCursor cursor = new LogEntryCursor(logEntryReader, recoveredDataChannel)) {
            LogEntry entry;
            while (cursor.next()) {
                entry = cursor.get();
                if (entry instanceof CheckPoint) {
                    latestCheckPoint = entry.as();
                }
                if (entry instanceof LogEntryStart) {
                    LogEntryStart startEntry = entry.as();
                    if (version == versionToSearchForCommits) {
                        latestStartEntry = startEntry;
                    }
                    // Oldest start entry will be the first in the last log version scanned.
                    if (firstStartEntry) {
                        oldestStartEntry = startEntry;
                        firstStartEntry = false;
                    }
                }
            }
        }
        if (latestCheckPoint != null) {
            return latestCheckPoint(fromVersionBackwards, version, latestStartEntry, oldestVersionFound, latestCheckPoint);
        }
        version--;
        // if we have found no commits in the latest log, keep searching in the next one
        if (latestStartEntry == null) {
            versionToSearchForCommits--;
        }
    }
    boolean commitsAfterCheckPoint = oldestStartEntry != null;
    long firstTxAfterPosition = commitsAfterCheckPoint ? extractFirstTxIdAfterPosition(oldestStartEntry.getStartPosition(), fromVersionBackwards) : LatestCheckPoint.NO_TRANSACTION_ID;
    return new LatestCheckPoint(null, commitsAfterCheckPoint, firstTxAfterPosition, oldestVersionFound);
}

Example 18 with LogEntry

use of org.neo4j.kernel.impl.transaction.log.entry.LogEntry in project neo4j by neo4j.

the class LatestCheckPointFinder method extractFirstTxIdAfterPosition.

/**
     * Extracts txId from first commit entry, when starting reading at the given {@code position}.
     * If no commit entry found in the version, the reader will continue into next version(s) up till
     * {@code maxLogVersion} until finding one.
     *
     * @param initialPosition {@link LogPosition} to start scan from.
     * @param maxLogVersion max log version to scan.
     * @return txId of closes commit entry to {@code initialPosition}, or {@link LatestCheckPoint#NO_TRANSACTION_ID}
     * if not found.
     * @throws IOException on I/O error.
     */
private long extractFirstTxIdAfterPosition(LogPosition initialPosition, long maxLogVersion) throws IOException {
    LogPosition currentPosition = initialPosition;
    while (currentPosition.getLogVersion() <= maxLogVersion) {
        LogVersionedStoreChannel storeChannel = PhysicalLogFile.tryOpenForVersion(logFiles, fileSystem, currentPosition.getLogVersion(), false);
        if (storeChannel != null) {
            try {
                storeChannel.position(currentPosition.getByteOffset());
                try (ReadAheadLogChannel logChannel = new ReadAheadLogChannel(storeChannel, NO_MORE_CHANNELS);
                    LogEntryCursor cursor = new LogEntryCursor(logEntryReader, logChannel)) {
                    while (cursor.next()) {
                        LogEntry entry = cursor.get();
                        if (entry instanceof LogEntryCommit) {
                            return ((LogEntryCommit) entry).getTxId();
                        }
                    }
                }
            } finally {
                storeChannel.close();
            }
        }
        currentPosition = LogPosition.start(currentPosition.getLogVersion() + 1);
    }
    return LatestCheckPoint.NO_TRANSACTION_ID;
}

Example 19 with LogEntry

use of org.neo4j.kernel.impl.transaction.log.entry.LogEntry in project neo4j by neo4j.

the class LogTruncationTest method assertHandlesLogTruncation.

private void assertHandlesLogTruncation(Command cmd) throws IOException {
    inMemoryChannel.reset();
    writer.serialize(new PhysicalTransactionRepresentation(Arrays.asList(cmd)));
    int bytesSuccessfullyWritten = inMemoryChannel.writerPosition();
    try {
        LogEntry logEntry = logEntryReader.readLogEntry(inMemoryChannel);
        StorageCommand command = ((LogEntryCommand) logEntry).getXaCommand();
        assertEquals(cmd, command);
    } catch (Exception e) {
        throw new AssertionError("Failed to deserialize " + cmd.toString() + ", because: ", e);
    }
    bytesSuccessfullyWritten--;
    while (bytesSuccessfullyWritten-- > 0) {
        inMemoryChannel.reset();
        writer.serialize(new PhysicalTransactionRepresentation(Arrays.asList(cmd)));
        inMemoryChannel.truncateTo(bytesSuccessfullyWritten);
        LogEntry deserialized = logEntryReader.readLogEntry(inMemoryChannel);
        assertNull("Deserialization did not detect log truncation!" + "Record: " + cmd + ", deserialized: " + deserialized, deserialized);
    }
}

Example 20 with LogEntry

use of org.neo4j.kernel.impl.transaction.log.entry.LogEntry in project neo4j by neo4j.

the class PhysicalTransactionCursor method next.

@Override
public boolean next() throws IOException {
    // Clear the previous deserialized transaction so that it won't have to be kept in heap while deserializing
    // the next one. Could be problematic if both are really big.
    current = null;
    while (true) {
        if (!logEntryCursor.next()) {
            return false;
        }
        LogEntry entry = logEntryCursor.get();
        if (entry instanceof LogEntryInlinedCheckPoint) {
            // this is a good position anyhow
            channel.getCurrentPosition(lastGoodPositionMarker);
            continue;
        }
        assert entry instanceof LogEntryStart : "Expected Start entry, read " + entry + " instead";
        LogEntryStart startEntry = (LogEntryStart) entry;
        LogEntryCommit commitEntry;
        List<StorageCommand> entries = new ArrayList<>();
        while (true) {
            if (!logEntryCursor.next()) {
                return false;
            }
            entry = logEntryCursor.get();
            if (entry instanceof LogEntryCommit) {
                commitEntry = (LogEntryCommit) entry;
                break;
            }
            LogEntryCommand command = (LogEntryCommand) entry;
            entries.add(command.getCommand());
        }
        PhysicalTransactionRepresentation transaction = new PhysicalTransactionRepresentation(entries);
        transaction.setHeader(startEntry.getAdditionalHeader(), startEntry.getTimeWritten(), startEntry.getLastCommittedTxWhenTransactionStarted(), commitEntry.getTimeWritten(), -1, ANONYMOUS);
        current = new CommittedTransactionRepresentation(startEntry, transaction, commitEntry);
        channel.getCurrentPosition(lastGoodPositionMarker);
        return true;
    }
}