[♻️Housekeeping] Remove BufferPool class and use .net implementation

LiteDB/Engine/Disk/DiskService.cs

@@ -1,4 +1,5 @@
 using System;
+using System.Buffers;
 using System.Collections.Generic;
 using System.IO;
 using System.Threading;
@@ -25,6 +26,8 @@ internal class DiskService : IDisposable
         private long _dataLength;
         private long _logLength;
 
+        private static readonly ArrayPool<byte> bufferPool = ArrayPool<byte>.Shared;
+
         public DiskService(
             EngineSettings settings,
             EngineState state,
@@ -222,11 +225,12 @@ internal void MarkAsInvalidState()
             {
                 using (var stream = _dataFactory.GetStream(true, true))
                 {
-                    var buffer = new byte[PAGE_SIZE];
+                    var buffer = bufferPool.Rent(PAGE_SIZE);
                     stream.Read(buffer, 0, PAGE_SIZE);
                     buffer[HeaderPage.P_INVALID_DATAFILE_STATE] = 1;
                     stream.Position = 0;
                     stream.Write(buffer, 0, PAGE_SIZE);
+                    bufferPool.Return(buffer);
                 }
             });
         }

LiteDB/Engine/Disk/Serializer/BufferReader.cs

@@ -1,7 +1,7 @@
 using System;
+using System.Buffers;
 using System.Collections.Generic;
 using System.IO;
-using System.Text;
 using static LiteDB.Constants;
 
 namespace LiteDB.Engine
@@ -20,6 +20,8 @@ internal class BufferReader : IDisposable
 
         private bool _isEOF = false;
 
+        private static readonly ArrayPool<byte> bufferPool = ArrayPool<byte>.Shared;
+
         /// <summary>
         /// Current global cursor position
         /// </summary>
@@ -102,10 +104,10 @@ public int Read(byte[] buffer, int offset, int count)
                 // fill buffer
                 if (buffer != null)
                 {
-                    Buffer.BlockCopy(_current.Array, 
-                        _current.Offset + _currentPosition, 
-                        buffer, 
-                        offset + bufferPosition, 
+                    Buffer.BlockCopy(_current.Array,
+                        _current.Offset + _currentPosition,
+                        buffer,
+                        offset + bufferPosition,
                         bytesToCopy);
                 }
 
@@ -161,13 +163,13 @@ public string ReadString(int count)
             else
             {
                 // rent a buffer to be re-usable
-                var buffer = BufferPool.Rent(count);
+                var buffer = bufferPool.Rent(count);
 
                 this.Read(buffer, 0, count);
 
                 value = StringEncoding.UTF8.GetString(buffer, 0, count);
 
-                BufferPool.Return(buffer);
+                bufferPool.Return(buffer);
             }
 
             return value;
@@ -251,13 +253,13 @@ private T ReadNumber<T>(Func<byte[], int, T> convert, int size)
             }
             else
             {
-                var buffer = BufferPool.Rent(size);
+                var buffer = bufferPool.Rent(size);
 
                 this.Read(buffer, 0, size);
 
                 value = convert(buffer, 0);
 
-                BufferPool.Return(buffer);
+                bufferPool.Return(buffer);
             }
 
             return value;
@@ -328,13 +330,13 @@ public ObjectId ReadObjectId()
             }
             else
             {
-                var buffer = BufferPool.Rent(12);
+                var buffer = bufferPool.Rent(12);
 
                 this.Read(buffer, 0, 12);
 
                 value = new ObjectId(buffer, 0);
 
-                BufferPool.Return(buffer);
+                bufferPool.Return(buffer);
             }
 
             return value;
@@ -393,7 +395,7 @@ public BsonValue ReadIndexKey()
                 case BsonType.Int64: return this.ReadInt64();
                 case BsonType.Double: return this.ReadDouble();
                 case BsonType.Decimal: return this.ReadDecimal();
-                
+
                 // Use +1 byte only for length
                 case BsonType.String: return this.ReadString(this.ReadByte());
 

LiteDB/Engine/Disk/Serializer/BufferWriter.cs

@@ -1,4 +1,5 @@
 using System;
+using System.Buffers;
 using System.Collections.Generic;
 using System.Text;
 using static LiteDB.Constants;
@@ -18,6 +19,8 @@ internal class BufferWriter : IDisposable
 
         private bool _isEOF = false;
 
+        private static readonly ArrayPool<byte> bufferPool = ArrayPool<byte>.Shared;
+
         /// <summary>
         /// Current global cursor position
         /// </summary>
@@ -98,10 +101,10 @@ public int Write(byte[] buffer, int offset, int count)
                 // fill buffer
                 if (buffer != null)
                 {
-                    Buffer.BlockCopy(buffer, 
+                    Buffer.BlockCopy(buffer,
                         offset + bufferPosition,
                         _current.Array,
-                        _current.Offset + _currentPosition, 
+                        _current.Offset + _currentPosition,
                         bytesToCopy);
                 }
 
@@ -133,7 +136,7 @@ public int Write(byte[] buffer, int offset, int count)
         /// </summary>
         public void Consume()
         {
-            if(_source != null)
+            if (_source != null)
             {
                 while (_source.MoveNext())
                 {
@@ -166,7 +169,7 @@ public void WriteCString(string value)
             }
             else
             {
-                var buffer = BufferPool.Rent(bytesCount);
+                var buffer = bufferPool.Rent(bytesCount);
 
                 StringEncoding.UTF8.GetBytes(value, 0, value.Length, buffer, 0);
 
@@ -176,7 +179,7 @@ public void WriteCString(string value)
 
                 this.MoveForward(1);
 
-                BufferPool.Return(buffer);
+                bufferPool.Return(buffer);
             }
         }
 
@@ -202,13 +205,13 @@ public void WriteString(string value, bool specs)
             else
             {
                 // rent a buffer to be re-usable
-                var buffer = BufferPool.Rent(count);
+                var buffer = bufferPool.Rent(count);
 
                 StringEncoding.UTF8.GetBytes(value, 0, value.Length, buffer, 0);
 
                 this.Write(buffer, 0, count);
 
-                BufferPool.Return(buffer);
+                bufferPool.Return(buffer);
             }
 
             if (specs)
@@ -231,13 +234,13 @@ private void WriteNumber<T>(T value, Action<T, byte[], int> toBytes, int size)
             }
             else
             {
-                var buffer = BufferPool.Rent(size);
+                var buffer = bufferPool.Rent(size);
 
                 toBytes(value, buffer, 0);
 
                 this.Write(buffer, 0, size);
 
-                BufferPool.Return(buffer);
+                bufferPool.Return(buffer);
             }
         }
 
@@ -293,13 +296,13 @@ public void Write(ObjectId value)
             }
             else
             {
-                var buffer = BufferPool.Rent(12);
+                var buffer = bufferPool.Rent(12);
 
                 value.ToByteArray(buffer, 0);
 
                 this.Write(buffer, 0, 12);
 
-                BufferPool.Return(buffer);
+                bufferPool.Return(buffer);
             }
         }
 

LiteDB/Engine/Disk/Streams/AesStream.cs

@@ -1,4 +1,5 @@
 using System;
+using System.Buffers;
 using System.IO;
 using System.Linq;
 using System.Security.Cryptography;
@@ -24,6 +25,8 @@ public class AesStream : Stream
 
         private static readonly byte[] _emptyContent = new byte[PAGE_SIZE - 1 - 16]; // 1 for aes indicator + 16 for salt
 
+        private static readonly ArrayPool<byte> bufferPool = ArrayPool<byte>.Shared;
+
         public byte[] Salt { get; }
 
         public override bool CanRead => _stream.CanRead;
@@ -52,6 +55,9 @@ public AesStream(string password, Stream stream)
             // start stream from zero position
             _stream.Position = 0;
 
+            var checkBuffer = bufferPool.Rent(32);
+            var msBuffer = bufferPool.Rent(16);
+
             try
             {
                 // new file? create new salt
@@ -104,7 +110,6 @@ public AesStream(string password, Stream stream)
                 // set stream to password checking
                 _stream.Position = 32;
 
-                var checkBuffer = new byte[32];
 
                 if (!isNew)
                 {
@@ -140,8 +145,7 @@ public AesStream(string password, Stream stream)
 
                 _stream.Position = PAGE_SIZE;
                 _stream.FlushToDisk();
-
-                using (var ms = new MemoryStream(new byte[16]))
+                using (var ms = new MemoryStream(msBuffer))
                 using (var tempStream = new CryptoStream(ms, _decryptor, CryptoStreamMode.Read))
                 {
                     tempStream.Read(_decryptedZeroes, 0, _decryptedZeroes.Length);
@@ -153,6 +157,11 @@ public AesStream(string password, Stream stream)
 
                 throw;
             }
+            finally
+            {
+                bufferPool.Return(msBuffer);
+                bufferPool.Return(checkBuffer);
+            }
         }
 
         /// <summary>

LiteDB/Engine/Engine/Upgrade.cs

@@ -1,4 +1,5 @@
 using System;
+using System.Buffers;
 using System.Collections.Generic;
 using System.IO;
 using System.Linq;
@@ -9,6 +10,9 @@ namespace LiteDB.Engine
 {
     public partial class LiteEngine
     {
+
+        private static readonly ArrayPool<byte> bufferPool = ArrayPool<byte>.Shared;
+
         /// <summary>
         /// If Upgrade=true, run this before open Disk service
         /// </summary>
@@ -19,20 +23,21 @@ private void TryUpgrade()
             // if file not exists, just exit
             if (!File.Exists(filename)) return;
 
+            var buffer = bufferPool.Rent(1024);
             using (var stream = new FileStream(
                 _settings.Filename,
                 FileMode.Open,
                 FileAccess.Read,
                 FileShare.Read, 1024))
             {
-                var buffer = new byte[1024];
+
 
                 stream.Position = 0;
                 stream.Read(buffer, 0, buffer.Length);
 
                 if (FileReaderV7.IsVersion(buffer) == false) return;
             }
-
+            bufferPool.Return(buffer);
             // run rebuild process
             this.Recovery(_settings.Collation);
         }

LiteDB/Engine/FileReader/FileReaderV7.cs

@@ -25,6 +25,7 @@ internal class FileReaderV7 : IFileReader
 
         private byte[] _buffer = new byte[V7_PAGE_SIZE];
         private bool _disposedValue;
+        private static readonly byte[] arrayByteEmpty = new byte[0];
 
         public IDictionary<string, BsonValue> GetPragmas() => new Dictionary<string, BsonValue>()
         {
@@ -387,7 +388,7 @@ private byte[] ReadExtendData(uint extendPageID)
                 {
                     var page = this.ReadPage(extendPageID);
 
-                    if (page["pageType"].AsInt32 != 5) return new byte[0];
+                    if (page["pageType"].AsInt32 != 5) return arrayByteEmpty;
 
                     buffer.Write(page["data"].AsBinary, 0, page["itemCount"].AsInt32);
 
@@ -403,10 +404,14 @@ private byte[] ReadExtendData(uint extendPageID)
         /// </summary>
         private HashSet<uint> VisitIndexPages(uint startPageID)
         {
-            var toVisit = new HashSet<uint>(new uint[] { startPageID });
+            var toVisit = new HashSet<uint>
+            {
+                startPageID
+            };
+
             var visited = new HashSet<uint>();
 
-            while(toVisit.Count > 0)
+            while (toVisit.Count > 0)
             {
                 var indexPageID = toVisit.First();