private static Item GetCurrentItem(JsonOperationContext ctx, TableValueReader reader)
{
int size;
return(new Item
{
Data = new BlittableJsonReaderObject(reader.Read(2, out size), size, ctx),
Key = Encoding.UTF8.GetString(reader.Read(1, out size), size),
Etag = Bits.SwapBytes(*(long *)reader.Read(3, out size))
});
}
public long ReadLastEtag(TransactionOperationContext ctx)
{
var table = ctx.Transaction.InnerTransaction.OpenTable(_itemsSchema, "Items");
var itemsFromBackwards = table.SeekBackwardFrom(_itemsSchema.FixedSizeIndexes[EtagIndexName], long.MaxValue);
var reader = itemsFromBackwards.FirstOrDefault();
if (reader == null)
{
return(0);
}
int size;
return(Bits.SwapBytes(*(long *)reader.Read(3, out size)));
}
public unsafe int GetHashCode(StringSegment str)
{
if (_buffer == null || _buffer.Length < str.Length)
{
_buffer = new char[Bits.NextPowerOf2(str.Length)];
}
for (int i = 0; i < str.Length; i++)
{
_buffer[i] = char.ToUpperInvariant(str.String[str.Start + i]);
}
fixed(char *p = _buffer)
{
return((int)Hashing.XXHash32.CalculateInline((byte *)p, str.Length * sizeof(char)));
}
}
public Tuple <BlittableJsonReaderObject, long> ReadWithEtag(TransactionOperationContext ctx, string id)
{
var items = ctx.Transaction.InnerTransaction.OpenTable(_itemsSchema, "Items");
TableValueReader reader;
Slice key;
using (Slice.From(ctx.Allocator, id.ToLowerInvariant(), out key))
{
reader = items.ReadByKey(key);
}
if (reader == null)
{
return(null);
}
int size;
var ptr = reader.Read(2, out size);
return(Tuple.Create(new BlittableJsonReaderObject(ptr, size, ctx), Bits.SwapBytes(*(long *)reader.Read(3, out size))));
}
public unsafe int GetHashCode(StringSegment str)
{
if (_buffer == null || _buffer.Length < str.Length)
{
_buffer = new char[Bits.NextPowerOf2(str.Length)];
}
for (int i = 0; i < str.Length; i++)
{
_buffer[i] = char.ToUpperInvariant(str.Buffer[str.Offset + i]);
}
fixed(char *p = _buffer)
{
//PERF: JIT will remove the corresponding line based on the target architecture using dead code removal.
if (IntPtr.Size == 4)
{
return((int)Hashing.XXHash32.CalculateInline((byte *)p, str.Length * sizeof(char)));
}
return((int)Hashing.XXHash64.CalculateInline((byte *)p, (ulong)str.Length * sizeof(char)));
}
}
public long Write(TransactionOperationContext ctx, string id, BlittableJsonReaderObject doc, long?expectedEtag = null)
{
TrackChangeAfterTransactionCommit(ctx, "Write", id);
var newEtag = _lastEtag + 1;
Slice idAsSlice;
Slice loweredId;
using (Slice.From(ctx.Allocator, id, out idAsSlice))
using (Slice.From(ctx.Allocator, id.ToLowerInvariant(), out loweredId))
{
var newEtagBigEndian = Bits.SwapBytes(newEtag);
var itemTable = ctx.Transaction.InnerTransaction.OpenTable(_itemsSchema, "Items");
var oldValue = itemTable.ReadByKey(loweredId);
if (oldValue == null)
{
if (expectedEtag != null && expectedEtag != 0)
{
throw new ConcurrencyException(
$"Server store item {id} does not exists, but Write was called with etag {expectedEtag}. Optimistic concurrency violation, transaction will be aborted.")
{
ExpectedETag = (long)expectedEtag
};
}
itemTable.Insert(new TableValueBuilder
{
loweredId,
idAsSlice,
{ doc.BasePointer, doc.Size },
{&newEtagBigEndian, sizeof(long) }
});
}
else
{
int size;
var test = GetCurrentItem(ctx, oldValue);
var oldEtag = Bits.SwapBytes(*(long *)oldValue.Read(3, out size));
if (expectedEtag != null && oldEtag != expectedEtag)
{
throw new ConcurrencyException(
$"Server store item {id} has etag {oldEtag}, but Write was called with etag {expectedEtag}. Optimistic concurrency violation, transaction will be aborted.")
{
ActualETag = oldEtag,
ExpectedETag = (long)expectedEtag
}
}
;
itemTable.Update(oldValue.Id, new TableValueBuilder
{
loweredId,
idAsSlice,
{ doc.BasePointer, doc.Size },
{&newEtagBigEndian, sizeof(long) }
});
}
}
_lastEtag++;
return(newEtag);
}
public void Initialize()
{
_shutdownNotification = new CancellationTokenSource();
AbstractLowMemoryNotification.Initialize(ServerShutdown, Configuration);
if (_logger.IsInfoEnabled)
{
_logger.Info("Starting to open server store for " + (Configuration.Core.RunInMemory ? "<memory>" : Configuration.Core.DataDirectory));
}
var options = Configuration.Core.RunInMemory
? StorageEnvironmentOptions.CreateMemoryOnly(Configuration.Core.DataDirectory)
: StorageEnvironmentOptions.ForPath(System.IO.Path.Combine(Configuration.Core.DataDirectory, "System"));
options.SchemaVersion = 2;
try
{
StorageEnvironment.MaxConcurrentFlushes = Configuration.Storage.MaxConcurrentFlushes;
_env = new StorageEnvironment(options);
using (var tx = _env.WriteTransaction())
{
tx.DeleteTree("items");// note the different casing, we remove the old items tree
_itemsSchema.Create(tx, "Items", 16);
tx.Commit();
}
using (var tx = _env.ReadTransaction())
{
var table = tx.OpenTable(_itemsSchema, "Items");
var itemsFromBackwards = table.SeekBackwardFrom(_itemsSchema.FixedSizeIndexes[EtagIndexName], long.MaxValue);
var reader = itemsFromBackwards.FirstOrDefault();
if (reader == null)
{
_lastEtag = 0;
}
else
{
int size;
_lastEtag = Bits.SwapBytes(*(long *)reader.Read(3, out size));
}
}
}
catch (Exception e)
{
if (_logger.IsOperationsEnabled)
{
_logger.Operations(
"Could not open server store for " + (Configuration.Core.RunInMemory ? "<memory>" : Configuration.Core.DataDirectory), e);
}
options.Dispose();
throw;
}
ContextPool = new TransactionContextPool(_env);
_timer = new Timer(IdleOperations, null, _frequencyToCheckForIdleDatabases, TimeSpan.FromDays(7));
Alerts.Initialize(_env, ContextPool);
DatabaseInfoCache.Initialize(_env, ContextPool);
LicenseStorage.Initialize(_env, ContextPool);
}
