Esempio n. 1
0
        public Usage Count_Empty_Slots()
        {
            int  invalid   = 0;
            int  valid     = 0;
            int  blockSize = _node_Factory.Size_In_Bytes(3);
            long position  = Index_Stream.Position;

            Index_Stream.Seek(8, SeekOrigin.Begin);
            var buffer = new byte[blockSize];

            while (Index_Stream.Read(buffer, 0, buffer.Length) > 0)
            {
                var node = _node_Factory.From_Bytes(buffer, 3);
                if (node.IsValid)
                {
                    valid++;
                }
                else
                {
                    invalid++;
                }
            }

            int used   = valid * blockSize;
            int wasted = invalid * blockSize;

            Index_Stream.Seek(position, SeekOrigin.Begin);
            return(new Usage {
                Invalid = invalid, Valid = valid
            });
        }
        protected Node <T> Read_Node(long address)
        {
            var buffer = new byte[_block_Size];

            Index_Stream.Seek(address, SeekOrigin.Begin);
            Index_Stream.Read(buffer, 0, buffer.Length);

            return(_node_Factory.From_Bytes(buffer, Order));
        }
Esempio n. 3
0
        public void Commit()
        {
            if (!_pending_Changes.Has_Pending_Changes())
            {
                return;
            }
            foreach (var address in _pending_Changes.Get_Freed_Empty_Slots())
            {
                _cache.Invalidate(address);
            }

            var newRoot = _pending_Changes.Commit(Index_Stream, Data_Stream);

            writes++;
            Metadata_Stream.Seek(0, SeekOrigin.Begin);
            var buffer = new byte[512];

            _metadata.DataStream_Length     = _pending_Changes.Get_Current_Data_Pointer();
            _metadata.IndexStream_Length    = _pending_Changes.Get_Index_Pointer();
            _metadata.Root_Address          = newRoot.Address;
            _metadata.Clustered_Data_Length = Cluster_Data_Length;
            _metadata.Alignment             = Alignment;
            _metadata.Number_Of_Keys       += key_added;
            _metadata.Number_Of_Leaves     += leaves_added;
            _metadata.Number_Of_Nodes      += nodes_added;
            _metadata.Height = 0;

            _metadata.To_Bytes_In_Buffer(buffer, 0);
            Metadata_Stream.Write(buffer, 0, buffer.Length);
            Metadata_Stream.Flush();

            Root = newRoot;

            _pending_Changes.Clean_Root();

            key_added = leaves_added = nodes_added = 0;
            // TODO persist empty pages on metadata ?
            //Cached_Nodes.Clear();
            //foreach (var node in Pending_Changes.Last_Cached_Nodes())
            //    Cached_Nodes[node.Address] = node;

            _index_Pointer = _pending_Changes.Get_Index_Pointer();

            Index_Stream.Flush();
        }
Esempio n. 4
0
 public void Mark_As_Invalid(Stream index, long block_Address)
 {
     Index_Stream.Seek(block_Address, SeekOrigin.Begin);
     Index_Stream.Write(BitConverter.GetBytes(-1), 0, 4);
 }
Esempio n. 5
0
 public void Dispose()
 {
     Index_Stream.Dispose();
     Metadata_Stream.Dispose();
     Data_Stream.Dispose();
 }
Esempio n. 6
0
 public void Flush()
 {
     Index_Stream.Flush();
 }