public EnvironmentStats Stats()
{
var transactionPersistentContext = new TransactionPersistentContext();
using (var tx = NewLowLevelTransaction(transactionPersistentContext, TransactionFlags.Read))
{
var numberOfAllocatedPages = Math.Max(_dataPager.NumberOfAllocatedPages, State.NextPageNumber - 1); // async apply to data file task
return(new EnvironmentStats
{
FreePagesOverhead = FreeSpaceHandling.GetFreePagesOverhead(tx),
RootPages = tx.RootObjects.State.PageCount,
UnallocatedPagesAtEndOfFile = _dataPager.NumberOfAllocatedPages - NextPageNumber,
UsedDataFileSizeInBytes = (State.NextPageNumber - 1) * Constants.Storage.PageSize,
AllocatedDataFileSizeInBytes = numberOfAllocatedPages * Constants.Storage.PageSize,
NextWriteTransactionId = NextWriteTransactionId,
ActiveTransactions = ActiveTransactions.AllTransactions
});
}
}
private void UpgradeSchemaIfRequired()
{
int schemaVersionVal;
var readPersistentContext = new TransactionPersistentContext(true);
using (var readTxInner = NewLowLevelTransaction(readPersistentContext, TransactionFlags.Read))
using (var readTx = new Transaction(readTxInner))
{
var metadataTree = readTx.ReadTree(Constants.MetadataTreeNameSlice);
var schemaVersion = metadataTree.Read("schema-version");
if (schemaVersion == null)
{
VoronUnrecoverableErrorException.Raise(this, "Could not find schema version in metadata tree, possible mismatch / corruption?");
}
schemaVersionVal = schemaVersion.Reader.ReadLittleEndianInt32();
}
if (Options.SchemaVersion != 0 &&
schemaVersionVal != Options.SchemaVersion)
{
if (schemaVersionVal > Options.SchemaVersion)
{
ThrowSchemaUpgradeRequired(schemaVersionVal, "You have a schema version is newer than the current supported version.");
}
Func <Transaction, Transaction, int, bool> upgrader = Options.SchemaUpgrader;
if (upgrader == null)
{
ThrowSchemaUpgradeRequired(schemaVersionVal, "You need to upgrade the schema but there is no schema uprader provided.");
}
UpgradeSchema(schemaVersionVal, upgrader);
}
}
internal LowLevelTransaction NewLowLevelTransaction(TransactionPersistentContext transactionPersistentContext, TransactionFlags flags, ByteStringContext context = null, TimeSpan?timeout = null)
{
_cancellationTokenSource.Token.ThrowIfCancellationRequested();
bool txLockTaken = false;
bool flushInProgressReadLockTaken = false;
try
{
IncrementUsageOnNewTransaction();
if (flags == TransactionFlags.ReadWrite)
{
var wait = timeout ?? (Debugger.IsAttached ? TimeSpan.FromMinutes(30) : TimeSpan.FromSeconds(30));
if (FlushInProgressLock.IsWriteLockHeld == false)
{
flushInProgressReadLockTaken = FlushInProgressLock.TryEnterReadLock(wait);
}
txLockTaken = _transactionWriter.Wait(wait);
if (txLockTaken == false || (flushInProgressReadLockTaken == false &&
FlushInProgressLock.IsWriteLockHeld == false))
{
GlobalFlushingBehavior.GlobalFlusher.Value.MaybeFlushEnvironment(this);
ThrowOnTimeoutWaitingForWriteTxLock(wait);
}
_cancellationTokenSource.Token.ThrowIfCancellationRequested();
_currentTransactionHolder = NativeMemory.ThreadAllocations.Value;
WriteTransactionStarted();
if (_endOfDiskSpace != null)
{
_endOfDiskSpace.AssertCanContinueWriting();
_endOfDiskSpace = null;
Task.Run(IdleFlushTimer);
GlobalFlushingBehavior.GlobalFlusher.Value.MaybeFlushEnvironment(this);
}
}
LowLevelTransaction tx;
_txCommit.EnterReadLock();
try
{
_cancellationTokenSource.Token.ThrowIfCancellationRequested();
if (_currentTransactionHolder == null)
{
_currentTransactionHolder = NativeMemory.ThreadAllocations.Value;
}
long txId = flags == TransactionFlags.ReadWrite ? NextWriteTransactionId : CurrentReadTransactionId;
tx = new LowLevelTransaction(this, txId, transactionPersistentContext, flags, _freeSpaceHandling,
context)
{
FlushInProgressLockTaken = flushInProgressReadLockTaken,
CurrentTransactionHolder = _currentTransactionHolder
};
ActiveTransactions.Add(tx);
}
finally
{
_txCommit.ExitReadLock();
}
var state = _dataPager.PagerState;
tx.EnsurePagerStateReference(state);
return(tx);
}
catch (Exception)
{
try
{
if (txLockTaken)
{
_transactionWriter.Release();
}
if (flushInProgressReadLockTaken)
{
FlushInProgressLock.ExitReadLock();
}
}
finally
{
DecrementUsageOnTransactionCreationFailure();
}
throw;
}
}
public Transaction WriteTransaction(TransactionPersistentContext transactionPersistentContext, ByteStringContext context = null)
{
var writeTransaction = new Transaction(NewLowLevelTransaction(transactionPersistentContext, TransactionFlags.ReadWrite, context, null));
return(writeTransaction);
}
public Transaction ReadTransaction(TransactionPersistentContext transactionPersistentContext, ByteStringContext context = null)
{
return(new Transaction(NewLowLevelTransaction(transactionPersistentContext, TransactionFlags.Read, context)));
}
private unsafe void LoadExistingDatabase()
{
var header = stackalloc TransactionHeader[1];
bool hadIntegrityIssues = _journal.RecoverDatabase(header);
if (hadIntegrityIssues)
{
var message = _journal.Files.Count == 0 ? "Unrecoverable database" : "Database recovered partially. Some data was lost.";
_options.InvokeRecoveryError(this, message, null);
}
var entry = _headerAccessor.CopyHeader();
var nextPageNumber = (header->TransactionId == 0 ? entry.LastPageNumber : header->LastPageNumber) + 1;
State = new StorageEnvironmentState(null, nextPageNumber)
{
NextPageNumber = nextPageNumber,
Options = Options
};
_transactionsCounter = (header->TransactionId == 0 ? entry.TransactionId : header->TransactionId);
var transactionPersistentContext = new TransactionPersistentContext(true);
using (var tx = NewLowLevelTransaction(transactionPersistentContext, TransactionFlags.ReadWrite))
{
using (var root = Tree.Open(tx, null, Constants.RootTreeNameSlice, header->TransactionId == 0 ? &entry.Root : &header->Root))
{
tx.UpdateRootsIfNeeded(root);
using (var treesTx = new Transaction(tx))
{
var metadataTree = treesTx.ReadTree(Constants.MetadataTreeNameSlice);
if (metadataTree == null)
{
VoronUnrecoverableErrorException.Raise(this,
"Could not find metadata tree in database, possible mismatch / corruption?");
}
var dbId = metadataTree.Read("db-id");
if (dbId == null)
{
VoronUnrecoverableErrorException.Raise(this,
"Could not find db id in metadata tree, possible mismatch / corruption?");
}
var buffer = new byte[16];
var dbIdBytes = dbId.Reader.Read(buffer, 0, 16);
if (dbIdBytes != 16)
{
VoronUnrecoverableErrorException.Raise(this,
"The db id value in metadata tree wasn't 16 bytes in size, possible mismatch / corruption?");
}
var databseGuidId = _options.GenerateNewDatabaseId == false ? new Guid(buffer) : Guid.NewGuid();
DbId = databseGuidId;
FillBase64Id(databseGuidId);
if (_options.GenerateNewDatabaseId)
{
// save the new database id
metadataTree.Add("db-id", DbId.ToByteArray());
}
var schemaVersion = metadataTree.Read("schema-version");
if (schemaVersion == null)
{
VoronUnrecoverableErrorException.Raise(this,
"Could not find schema version in metadata tree, possible mismatch / corruption?");
}
var schemaVersionVal = schemaVersion.Reader.ReadLittleEndianInt32();
if (Options.SchemaVersion != 0 &&
schemaVersionVal != Options.SchemaVersion)
{
VoronUnrecoverableErrorException.Raise(this,
"The schema version of this database is expected to be " +
Options.SchemaVersion + " but is actually " + schemaVersionVal +
". You need to upgrade the schema.");
}
tx.Commit();
}
}
}
}
public TransactionsModeResult SetTransactionMode(TransactionsMode mode, TimeSpan duration)
{
var transactionPersistentContext = new TransactionPersistentContext();
using (var tx = NewLowLevelTransaction(transactionPersistentContext, TransactionFlags.ReadWrite))
{
var oldMode = Options.TransactionsMode;
if (_log.IsOperationsEnabled)
{
_log.Operations($"Setting transaction mode to {mode}. Old mode is {oldMode}");
}
if (oldMode == mode)
{
return(TransactionsModeResult.ModeAlreadySet);
}
Options.TransactionsMode = mode;
if (duration == TimeSpan.FromMinutes(0)) // infinite
{
Options.NonSafeTransactionExpiration = null;
}
else
{
Options.NonSafeTransactionExpiration = DateTime.Now + duration;
}
if (oldMode == TransactionsMode.Lazy)
{
tx.IsLazyTransaction = false;
// we only commit here, the rest of the of the options are without
// commit and we use the tx lock
tx.Commit();
}
if (oldMode == TransactionsMode.Danger)
{
Journal.TruncateJournal();
_dataPager.Sync(Journal.Applicator.TotalWrittenButUnsyncedBytes);
}
switch (mode)
{
case TransactionsMode.Safe:
case TransactionsMode.Lazy:
{
Options.PosixOpenFlags = Options.SafePosixOpenFlags;
Options.WinOpenFlags = StorageEnvironmentOptions.SafeWin32OpenFlags;
}
break;
case TransactionsMode.Danger:
{
Options.PosixOpenFlags = Options.DefaultPosixFlags;
Options.WinOpenFlags = Win32NativeFileAttributes.None;
Journal.TruncateJournal();
}
break;
default:
{
throw new InvalidOperationException("Query string value 'mode' is not a valid mode: " + mode);
}
}
return(TransactionsModeResult.SetModeSuccessfully);
}
}
internal LowLevelTransaction NewLowLevelTransaction(TransactionPersistentContext transactionPersistentContext, TransactionFlags flags, ByteStringContext context = null, TimeSpan?timeout = null)
{
bool txLockTaken = false;
bool flushInProgressReadLockTaken = false;
try
{
if (flags == TransactionFlags.ReadWrite)
{
var wait = timeout ?? (Debugger.IsAttached ? TimeSpan.FromMinutes(30) : TimeSpan.FromSeconds(30));
if (FlushInProgressLock.IsWriteLockHeld == false)
{
flushInProgressReadLockTaken = FlushInProgressLock.TryEnterReadLock(wait);
}
if (Monitor.IsEntered(_txWriter))
{
ThrowOnRecursiveWriteTransaction();
}
Monitor.TryEnter(_txWriter, wait, ref txLockTaken);
if (txLockTaken == false || (flushInProgressReadLockTaken == false && FlushInProgressLock.IsWriteLockHeld == false))
{
GlobalFlushingBehavior.GlobalFlusher.Value.MaybeFlushEnvironment(this);
ThrowOnTimeoutWaitingForWriteTxLock(wait);
}
_writeTransactionRunning.SetByAsyncCompletion();
if (_endOfDiskSpace != null)
{
if (_endOfDiskSpace.CanContinueWriting)
{
CatastrophicFailure = null;
_endOfDiskSpace = null;
_cancellationTokenSource = new CancellationTokenSource();
Task.Run(IdleFlushTimer);
GlobalFlushingBehavior.GlobalFlusher.Value.MaybeFlushEnvironment(this);
}
}
}
LowLevelTransaction tx;
_txCommit.EnterReadLock();
try
{
long txId = flags == TransactionFlags.ReadWrite ? _transactionsCounter + 1 : _transactionsCounter;
tx = new LowLevelTransaction(this, txId, transactionPersistentContext, flags, _freeSpaceHandling,
context)
{
FlushInProgressLockTaken = flushInProgressReadLockTaken
};
ActiveTransactions.Add(tx);
}
finally
{
_txCommit.ExitReadLock();
}
var state = _dataPager.PagerState;
tx.EnsurePagerStateReference(state);
return(tx);
}
catch (Exception)
{
if (txLockTaken)
{
Monitor.Exit(_txWriter);
}
if (flushInProgressReadLockTaken)
{
FlushInProgressLock.ExitReadLock();
}
throw;
}
}