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

Example 1 with ReadableLogChannel

use of org.neo4j.kernel.impl.transaction.log.ReadableLogChannel 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 2 with ReadableLogChannel

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

the class NeoStoreDataSource method buildTransactionLogs.

private NeoStoreTransactionLogModule buildTransactionLogs(File storeDir, Config config, LogProvider logProvider, JobScheduler scheduler, FileSystemAbstraction fileSystemAbstraction, StorageEngine storageEngine, LogEntryReader<ReadableClosablePositionAwareChannel> logEntryReader, SynchronizedArrayIdOrderingQueue legacyIndexTransactionOrdering, TransactionIdStore transactionIdStore, LogVersionRepository logVersionRepository) {
    TransactionMetadataCache transactionMetadataCache = new TransactionMetadataCache(100_000);
    LogHeaderCache logHeaderCache = new LogHeaderCache(1000);
    final PhysicalLogFiles logFiles = new PhysicalLogFiles(storeDir, PhysicalLogFile.DEFAULT_NAME, fileSystemAbstraction);
    final PhysicalLogFile logFile = life.add(new PhysicalLogFile(fileSystemAbstraction, logFiles, config.get(GraphDatabaseSettings.logical_log_rotation_threshold), transactionIdStore::getLastCommittedTransactionId, logVersionRepository, physicalLogMonitor, logHeaderCache));
    final PhysicalLogFileInformation.LogVersionToTimestamp logInformation = version -> {
        LogPosition position = LogPosition.start(version);
        try (ReadableLogChannel channel = logFile.getReader(position)) {
            LogEntry entry;
            while ((entry = logEntryReader.readLogEntry(channel)) != null) {
                if (entry instanceof LogEntryStart) {
                    return entry.<LogEntryStart>as().getTimeWritten();
                }
            }
        }
        return -1;
    };
    final LogFileInformation logFileInformation = new PhysicalLogFileInformation(logFiles, logHeaderCache, transactionIdStore::getLastCommittedTransactionId, logInformation);
    if (config.get(GraphDatabaseFacadeFactory.Configuration.ephemeral)) {
        config = config.withDefaults(stringMap(GraphDatabaseSettings.keep_logical_logs.name(), "1 files"));
    }
    String pruningConf = config.get(GraphDatabaseSettings.keep_logical_logs);
    LogPruneStrategy logPruneStrategy = fromConfigValue(fs, logFileInformation, logFiles, pruningConf);
    final LogPruning logPruning = new LogPruningImpl(logPruneStrategy, logProvider);
    final LogRotation logRotation = new LogRotationImpl(monitors.newMonitor(LogRotation.Monitor.class), logFile, databaseHealth);
    final TransactionAppender appender = life.add(new BatchingTransactionAppender(logFile, logRotation, transactionMetadataCache, transactionIdStore, legacyIndexTransactionOrdering, databaseHealth));
    final LogicalTransactionStore logicalTransactionStore = new PhysicalLogicalTransactionStore(logFile, transactionMetadataCache, logEntryReader);
    int txThreshold = config.get(GraphDatabaseSettings.check_point_interval_tx);
    final CountCommittedTransactionThreshold countCommittedTransactionThreshold = new CountCommittedTransactionThreshold(txThreshold);
    long timeMillisThreshold = config.get(GraphDatabaseSettings.check_point_interval_time);
    TimeCheckPointThreshold timeCheckPointThreshold = new TimeCheckPointThreshold(timeMillisThreshold, clock);
    CheckPointThreshold threshold = CheckPointThresholds.or(countCommittedTransactionThreshold, timeCheckPointThreshold);
    final CheckPointerImpl checkPointer = new CheckPointerImpl(transactionIdStore, threshold, storageEngine, logPruning, appender, databaseHealth, logProvider, tracers.checkPointTracer, ioLimiter, storeCopyCheckPointMutex);
    long recurringPeriod = Math.min(timeMillisThreshold, TimeUnit.SECONDS.toMillis(10));
    CheckPointScheduler checkPointScheduler = new CheckPointScheduler(checkPointer, scheduler, recurringPeriod, databaseHealth);
    life.add(checkPointer);
    life.add(checkPointScheduler);
    return new NeoStoreTransactionLogModule(logicalTransactionStore, logFileInformation, logFiles, logFile, logRotation, checkPointer, appender, legacyIndexTransactionOrdering);
}

Example 3 with ReadableLogChannel

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

the class CheckPointerIntegrationTest method checkPointInTxLog.

private boolean checkPointInTxLog(GraphDatabaseService db) throws IOException {
    LogFile logFile = ((GraphDatabaseAPI) db).getDependencyResolver().resolveDependency(LogFile.class);
    try (ReadableLogChannel reader = logFile.getReader(new LogPosition(0, LOG_HEADER_SIZE))) {
        LogEntryReader<ReadableClosablePositionAwareChannel> logEntryReader = new VersionAwareLogEntryReader<>();
        LogEntry entry = null;
        while ((entry = logEntryReader.readLogEntry(reader)) != null) {
            if (entry instanceof CheckPoint) {
                return true;
            }
        }
        return false;
    }
}

Example 4 with ReadableLogChannel

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

the class LogTestUtils method openLogEntryCursor.

private static LogEntryCursor openLogEntryCursor(FileSystemAbstraction fs, File firstFile, LogVersionBridge versionBridge) {
    StoreChannel channel = null;
    try {
        channel = fs.open(firstFile, "r");
        ByteBuffer buffer = ByteBuffer.allocate(LogHeader.LOG_HEADER_SIZE);
        LogHeader header = LogHeaderReader.readLogHeader(buffer, channel, true, firstFile);
        PhysicalLogVersionedStoreChannel logVersionedChannel = new PhysicalLogVersionedStoreChannel(channel, header.logVersion, header.logFormatVersion);
        ReadableLogChannel logChannel = new ReadAheadLogChannel(logVersionedChannel, versionBridge, ReadAheadLogChannel.DEFAULT_READ_AHEAD_SIZE);
        return new LogEntryCursor(new VersionAwareLogEntryReader<>(), logChannel);
    } catch (Throwable t) {
        if (channel != null) {
            try {
                channel.close();
            } catch (IOException e) {
                t.addSuppressed(e);
            }
        }
        throw new RuntimeException(t);
    }
}

Example 5 with ReadableLogChannel

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

the class LogMatchers method logEntries.

public static List<LogEntry> logEntries(FileSystemAbstraction fileSystem, String logPath) throws IOException {
    File logFile = new File(logPath);
    StoreChannel fileChannel = fileSystem.open(logFile, "r");
    // Always a header
    LogHeader header = readLogHeader(ByteBuffer.allocateDirect(LOG_HEADER_SIZE), fileChannel, true, logFile);
    // Read all log entries
    PhysicalLogVersionedStoreChannel versionedStoreChannel = new PhysicalLogVersionedStoreChannel(fileChannel, header.logVersion, header.logFormatVersion);
    ReadableLogChannel logChannel = new ReadAheadLogChannel(versionedStoreChannel, NO_MORE_CHANNELS);
    LogEntryCursor logEntryCursor = new LogEntryCursor(new VersionAwareLogEntryReader<>(), logChannel);
    return Iterables.asList(new IOCursorAsResourceIterable<>(logEntryCursor));
}