/// <summary>
/// This begins an async commit and starts a new transaction immediately.
/// The current transaction is considered completed in memory but not yet
/// committed to disk. This *must* be completed by calling EndAsyncCommit.
/// </summary>
public LowLevelTransaction BeginAsyncCommitAndStartNewTransaction()
{
if (Flags != TransactionFlags.ReadWrite)
{
ThrowReadTranscationCannotDoAsyncCommit();
}
if (_asyncCommitNextTransaction != null)
{
ThrowAsyncCommitAlreadyCalled();
}
// we have to check the state before we complete the transaction
// because that would change whether we need to write to the journal
var writeToJournalIsRequired = WriteToJournalIsRequired();
CommitStage1_CompleteTransaction();
var nextTx = new LowLevelTransaction(this,
writeToJournalIsRequired ? Id + 1 : Id
);
_asyncCommitNextTransaction = nextTx;
AsyncCommit = writeToJournalIsRequired
? Task.Run(() => { CommitStage2_WriteToJournal(); return(true); })
: NoWriteToJournalRequiredTask;
try
{
_env.IncrementUsageOnNewTransaction();
_env.ActiveTransactions.Add(nextTx);
_env.WriteTransactionStarted();
return(nextTx);
}
catch (Exception)
{
// failure here means that we'll try to complete the current transaction normaly
// then throw as if commit was called normally and the next transaction failed
_env.DecrementUsageOnTransactionCreationFailure();
EndAsyncCommit();
AsyncCommit = null;
_disposed |= TxState.Errored;
throw;
}
}
public void Dispose()
{
if (_trees != null)
{
foreach (var tree in _trees)
{
tree.Value?.Dispose();
}
}
if (_multiValueTrees != null)
{
foreach (var item in _multiValueTrees)
{
item.Value?.Dispose();
item.Key.Item1?.Dispose();
}
}
if (_tables != null)
{
foreach (var table in _tables)
{
table.Value?.Dispose();
}
}
if (_globalFixedSizeTree != null)
{
foreach (var tree in _globalFixedSizeTree)
{
tree.Value?.Dispose();
}
}
_lowLevelTransaction?.Dispose();
_lowLevelTransaction = null;
}
private LowLevelTransaction(LowLevelTransaction previous, long txId)
{
// this is meant to be used with transaction merging only
// so it makes a lot of assumptions about the usage scenario
// and what it can do
Debug.Assert(previous.Flags == TransactionFlags.ReadWrite);
var env = previous._env;
env.Options.AssertNoCatastrophicFailure();
FlushInProgressLockTaken = previous.FlushInProgressLockTaken;
CurrentTransactionHolder = previous.CurrentTransactionHolder;
TxStartTime = DateTime.UtcNow;
DataPager = env.Options.DataPager;
_env = env;
_journal = env.Journal;
_id = txId;
_freeSpaceHandling = previous._freeSpaceHandling;
_allocator = previous._allocator;
_disposeAllocator = previous._disposeAllocator;
previous._disposeAllocator = false;
PersistentContext = previous.PersistentContext;
Flags = TransactionFlags.ReadWrite;
_pagerStates = new HashSet <PagerState>(ReferenceEqualityComparer <PagerState> .Default);
JournalFiles = previous.JournalFiles;
foreach (var journalFile in JournalFiles)
{
journalFile.AddRef();
}
var pagers = new HashSet <AbstractPager>();
foreach (var scratchAndDataPagerState in previous._pagerStates)
{
// in order to avoid "dragging" pager state ref on non active scratch - we will not copy disposed scratches from previous async tx. RavenDB-6766
if (scratchAndDataPagerState.DiscardOnTxCopy)
{
continue;
}
// copy the "current pager" which is the last pager used, and by that do not "drag" old non used pager state refs to the next async commit (i.e. older views of data file). RavenDB-6949
var currentPager = scratchAndDataPagerState.CurrentPager;
if (pagers.Add(currentPager) == false)
{
continue;
}
var state = currentPager.PagerState;
state.AddRef();
_pagerStates.Add(state);
}
EnsureNoDuplicateTransactionId(_id);
// we can reuse those instances, not calling Reset on the pool
// because we are going to need to scratch buffer pool
_dirtyOverflowPages = previous._dirtyOverflowPages;
_dirtyOverflowPages.Clear();
_scratchPagesTable = _env.WriteTransactionPool.ScratchPagesReadyForNextTx;
foreach (var kvp in previous._scratchPagesTable)
{
if (previous._dirtyPages.Contains(kvp.Key))
{
_scratchPagesTable.Add(kvp.Key, kvp.Value);
}
}
previous._scratchPagesTable.Clear();
_env.WriteTransactionPool.ScratchPagesInUse = _scratchPagesTable;
_env.WriteTransactionPool.ScratchPagesReadyForNextTx = previous._scratchPagesTable;
_dirtyPages = previous._dirtyPages;
_dirtyPages.Clear();
_freedPages = new HashSet <long>(NumericEqualityComparer.BoxedInstanceInt64);
_unusedScratchPages = new List <PageFromScratchBuffer>();
_transactionPages = new HashSet <PageFromScratchBuffer>(PageFromScratchBufferEqualityComparer.Instance);
_pagesToFreeOnCommit = new Stack <long>();
_state = previous._state.Clone();
_pageLocator = PersistentContext.AllocatePageLocator(this);
InitializeRoots();
InitTransactionHeader();
}
public Transaction(LowLevelTransaction lowLevelTransaction)
{
_lowLevelTransaction = lowLevelTransaction;
}
public Transaction(LowLevelTransaction lowLevelTransaction)
{
_lowLevelTransaction = lowLevelTransaction;
_lowLevelTransaction.Transaction = this;
}
public static FixedSizeTreePage GetReadOnlyFixedSizeTreePage(this LowLevelTransaction tx, long pageNumber)
{
return(tx.GetPage(pageNumber).ToFixedSizeTreePage());
}