/// <summary>
/// Proper constructor.
/// </summary>
/// <param name="id">Store transaction id.</param>
/// <param name="isReadOnly">True, if the store transaction is read only.</param>
/// <param name="owner"></param>
/// <param name="replicatorTransaction"></param>
/// <param name="tracer"></param>
/// <param name="enableStrict2PL">Indicates whether strict 2PL is enabled.</param>
public StoreTransaction(
long id,
bool isReadOnly,
IStoreTransactionProvider owner,
ReplicatorTransactionBase replicatorTransaction,
string tracer,
bool enableStrict2PL)
{
this.id = id;
this.isReadOnly = isReadOnly;
this.tracer = tracer;
this.owner = owner;
this.replicatorTransactionBase = replicatorTransaction;
this.enableStrict2PL = enableStrict2PL;
}
/// <summary>
/// Locks for write.
/// </summary>
public async Task <StateManagerLockContext> LockForWriteAsync(
Uri key,
long stateProviderId,
TransactionBase transaction,
TimeSpan timeout,
CancellationToken cancellationToken)
{
Utility.Assert(
key != null,
"{0}: LockForWriteAsync: key != null. SPID: {1}",
this.traceType,
stateProviderId);
Utility.Assert(
stateProviderId != 0,
"{0}: LockForWriteAsync: stateProviderId is zero. Key: {1} SPID: {2}",
this.traceType,
key,
stateProviderId);
Utility.Assert(
transaction != null,
"{0}: LockForWriteAsync: transaction is null. Key: {1} SPID: {2}",
this.traceType,
key,
stateProviderId);
FabricEvents.Events.StateProviderMetadataManagerLockForWrite(
this.TraceType,
key.OriginalString,
stateProviderId,
transaction.Id);
StateManagerLockContext lockContext = null;
var incrementIndex = 0;
while (true)
{
lockContext = this.keylocks.GetOrAdd(key, k => new StateManagerLockContext(k, stateProviderId, this));
// If this transaction already has a write lock on the key lock, then do not acquire the lock, instead just increment the grantor count
if (lockContext.LockMode == StateManagerLockMode.Write &&
this.DoesTransactionContainKeyLock(transaction.Id, key))
{
// It is safe to do this grantor count increment outside the lock since this transaction already holds this lock.
lockContext.GrantorCount++;
break;
}
else if (lockContext.LockMode == StateManagerLockMode.Read &&
this.DoesTransactionContainKeyLock(transaction.Id, key))
{
// If this transaction has a read lock on the key lock, then release read lock and acquire the write lock.
// SM only supports read committed so it is okay to release this lock.
lockContext.Release(transaction.Id);
// Increment grantor count by 2 to account for both the operations, but after lock acquisition.
incrementIndex = 2;
}
else
{
incrementIndex = 1;
}
// With the removal of the global lock, when a lock is removed during an inflight transaction this exception can happen.
// It can be solved by either ref counting or handling disposed exception, since this is a rare situation and ref counting
// needs to be done every time. Gopalk has acked this recommendation.
try
{
await lockContext.AcquireWriteLockAsync(timeout, cancellationToken).ConfigureAwait(false);
lockContext.GrantorCount = lockContext.GrantorCount + incrementIndex;
break;
}
catch (ObjectDisposedException)
{
// Ignore and continue
}
catch (Exception e)
{
FabricEvents.Events.MetadataManagerAcquireWriteLockException(
this.TraceType,
key.OriginalString,
transaction.Id,
e.Message,
e.StackTrace);
throw;
}
}
HashSet <Uri> keyLocks = this.InflightTransactions.GetOrAdd(transaction.Id, k => new HashSet <Uri>(AbsoluteUriEqualityComparer.Comparer));
keyLocks.Add(key);
return(lockContext);
}
/// <summary>
/// The apply async.
/// </summary>
/// <param name="lsn">
/// The lsn.
/// </param>
/// <param name="transactionBase">
/// The transaction base.
/// </param>
/// <param name="data">
/// The data.
/// </param>
/// <param name="applyContext">
/// The apply context.
/// </param>
/// <returns>
/// The <see cref="Task"/>.
/// </returns>
Task <object> IStateProvider2.ApplyAsync(
long lsn,
TransactionBase transactionBase,
OperationData data,
ApplyContext applyContext)
{
// Get the operation.
var operation = Operation.Deserialize(data[0]);
// Resume the existing transaction for this operation or start a transaction for this operation.
bool applied;
OperationContext context;
DatabaseTransaction <TKey, TValue> tx;
if (IsPrimaryOperation(applyContext) && this.inProgressOperations.TryGetValue(operation.Id, out context))
{
applied = true;
tx = context.DatabaseTransaction;
tx.Resume();
}
else
{
// The operation has not yet been applied and therefore a transaction has not been initiated.
applied = false;
tx = this.tables.CreateTransaction();
}
/*var part = this.replicator.StatefulPartition;
* var operationString = JsonConvert.SerializeObject(operation, SerializationSettings.JsonConfig);
* Trace.TraceInformation(
* $"[{this.partitionId}/{this.replicator.InitializationParameters.ReplicaId} r:{part.ReadStatus} w:{part.WriteStatus}] ApplyAsync(lsn: {lsn}, tx: {transactionBase.Id}, op: {operationString} (length: {data?.Length ?? 0}), context: {applyContext})");
*/
try
{
// If the operation has not yet been applied, apply it.
if (!applied)
{
//Trace.TraceInformation($"{applyContext} Apply {operationString}");
operation.Apply(tx.Table);
}
//Trace.TraceInformation($"{applyContext} Commit {operationString}");
tx.Commit();
}
catch (Exception exception)
{
tx.Rollback();
return(Task.FromException <object>(exception));
}
finally
{
if (IsPrimaryOperation(applyContext))
{
this.inProgressOperations.TryRemove(operation.Id, out context);
}
tx.Dispose();
}
return(Task.FromResult(default(object)));
}
/// <summary>
/// Locks for read.
/// </summary>
public async Task <StateManagerLockContext> LockForReadAsync(
Uri key,
long stateProviderId,
TransactionBase transaction,
TimeSpan timeout,
CancellationToken cancellationToken)
{
Utility.Assert(
key != null,
"{0}: LockForReadAsync: key != null. SPID: {1}",
this.traceType,
stateProviderId);
Utility.Assert(
stateProviderId != 0,
"{0}: LockForReadAsync: stateProviderId is zero. Key: {1} SPID: {2}",
this.traceType,
key,
stateProviderId);
Utility.Assert(
transaction != null,
"{0}: LockForReadAsync: transaction is null. Key: {1} SPID: {2}",
this.traceType,
key,
stateProviderId);
StateManagerLockContext lockContext = null;
FabricEvents.Events.StateProviderMetadataManagerLockForRead(
this.TraceType,
key.OriginalString,
stateProviderId,
transaction.Id);
while (true)
{
lockContext = this.keylocks.GetOrAdd(key, k => new StateManagerLockContext(k, stateProviderId, this));
// If this transaction already has a write lock on the key lock, then do not acquire the lock, instead increment the grantor count.
// This check is needed only if the transaction is holding this key in the write mode, in the read mode it can acquire the read lock again
// as it will not cause a deadlock.
if (lockContext.LockMode == StateManagerLockMode.Write &&
this.DoesTransactionContainKeyLock(transaction.Id, key))
{
// It is safe to do this grantor count increment outside the lock since this transaction already holds a write lock.
// This lock is just treated as a write lock.
lockContext.GrantorCount++;
break;
}
// With the removal of the global lock, when a lock is removed during an inflight transaction this exception can happen.
// It can be solved by either ref counting or handling disposed exception, since this is a rare situation and ref counting
// needs to be done every time. Gopalk has acked this recommendation.
try
{
await lockContext.AcquireReadLockAsync(timeout, cancellationToken).ConfigureAwait(false);
break;
}
catch (ObjectDisposedException)
{
// Ignore and continue
}
catch (Exception e)
{
FabricEvents.Events.MetadataManagerAcquireReadLockException(
this.TraceType,
key.OriginalString,
transaction.Id,
e.Message,
e.StackTrace);
throw;
}
}
HashSet <Uri> keyLocks = this.InflightTransactions.GetOrAdd(transaction.Id, k => new HashSet <Uri>(AbsoluteUriEqualityComparer.Comparer));
keyLocks.Add(key);
return(lockContext);
}