private bool WriteToJournalIsRequired()
{
return(_dirtyPages.Count > 0 ||
_freedPages.Count > 0
// nothing changed in this transaction
// allow call to writeToJournal for flushing lazy tx
|| (IsLazyTransaction == false && _journal?.HasDataInLazyTxBuffer() == true));
}
public void Commit()
{
if (_disposed)
{
throw new ObjectDisposedException("Transaction");
}
if (Flags != (TransactionFlags.ReadWrite))
{
return; // nothing to do
}
if (Committed)
{
throw new InvalidOperationException("Cannot commit already committed transaction.");
}
if (RolledBack)
{
throw new InvalidOperationException("Cannot commit rolled-back transaction.");
}
while (_pagesToFreeOnCommit.Count > 0)
{
FreePage(_pagesToFreeOnCommit.Pop());
}
_txHeader->LastPageNumber = _state.NextPageNumber - 1;
_state.Root.CopyTo(&_txHeader->Root);
_txHeader->TxMarker |= TransactionMarker.Commit;
var totalNumberOfAllocatedPages = _allocatedPagesInTransaction + _overflowPagesInTransaction;
if (totalNumberOfAllocatedPages > 0 || // nothing changed in this transaction
// allow call to writeToJournal for flushing lazy tx
(IsLazyTransaction == false && _journal?.HasDataInLazyTxBuffer() == true))
{
// In the case of non-lazy transactions, we must flush the data from older lazy transactions
// to ensure the sequentiality of the data.
var numberOfWrittenPages = _journal.WriteToJournal(this, totalNumberOfAllocatedPages + PagesTakenByHeader);
FlushedToJournal = true;
if (_requestedCommitStats != null)
{
_requestedCommitStats.NumberOfModifiedPages = totalNumberOfAllocatedPages + PagesTakenByHeader;
_requestedCommitStats.NumberOfPagesWrittenToDisk = numberOfWrittenPages;
}
}
// an exception being throw after the transaction has been committed to disk
// will corrupt the in memory state, and require us to restart (and recover) to
// be in a valid state
try
{
ValidateAllPages();
// release scratch file page allocated for the transaction header
_env.ScratchBufferPool.Free(_transactionHeaderPage.ScratchFileNumber, _transactionHeaderPage.PositionInScratchBuffer, null);
Committed = true;
_env.TransactionAfterCommit(this);
}
catch (Exception e)
{
_env.CatastrophicFailure = ExceptionDispatchInfo.Capture(e);
throw;
}
OnCommit?.Invoke(this);
}