Revert "Use array pool input message buffer (#41)"

This reverts commit 7a95240.

benchmarks/Backdash.Benchmarks/Program.cs

@@ -1,5 +1,5 @@
 using BenchmarkDotNet.Running;
-
 BenchmarkSwitcher.FromAssembly(typeof(Program).Assembly).Run(args);
 // BenchmarkRunner.Run<GetBitStringBenchmark>();
-// BenchmarkRunner.Run<UdpClientBenchmark>();
+// BenchmarkRunner.Run<UdpClientBenchmark>();
+// await new UdpClientBenchmark().Start(10, false).ConfigureAwait(false);

src/Backdash/Network/Client/PeerClient.cs

@@ -78,6 +78,7 @@ async Task ReceiveLoop(CancellationToken ct)
     {
         var buffer = Mem.CreatePinnedMemory(maxPacketSize);
         SocketAddress address = new(socket.AddressFamily);
+        T msg = default;
         while (!ct.IsCancellationRequested)
         {
             int receivedSize;
@@ -113,7 +114,6 @@ async Task ReceiveLoop(CancellationToken ct)
 
             try
             {
-                T msg = new();
                 serializer.Deserialize(buffer[..receivedSize].Span, ref msg);
                 await observer.OnPeerMessage(msg, address, receivedSize, ct).ConfigureAwait(false);
             }

src/Backdash/Network/Messages/InputMessage.cs

@@ -1,6 +1,4 @@
-using System.Buffers;
 using System.Runtime.CompilerServices;
-using System.Runtime.InteropServices;
 using System.Text;
 using Backdash.Core;
 using Backdash.Data;
@@ -10,37 +8,19 @@
 namespace Backdash.Network.Messages;
 
 [Serializable]
-struct InputMessage : IDisposable, IBinarySerializable, IUtf8SpanFormattable, IEquatable<InputMessage>
+record struct InputMessage : IBinarySerializable, IUtf8SpanFormattable
 {
     public PeerStatusBuffer PeerConnectStatus;
     public Frame StartFrame;
     public bool DisconnectRequested;
     public Frame AckFrame;
     public ushort NumBits;
     public byte InputSize;
-    public Memory<byte> Bits = Memory<byte>.Empty;
-
-    public InputMessage() => InitBits();
-
-    public InputMessage(ReadOnlySpan<byte> bits) : this()
-    {
-        InitBits();
-        bits.CopyTo(Bits.Span);
-    }
-
-    public void InitBits()
-    {
-        var buffer = ArrayPool<byte>.Shared.Rent(Max.CompressedBytes);
-        buffer.AsSpan().Clear();
-        Bits = buffer;
-    }
-
-    public readonly int InputByteSize() => (int)Math.Ceiling(NumBits / (float)ByteSize.ByteToBits);
-    public readonly Memory<byte> InputBytes() => Bits[..InputByteSize()];
+    public InputMessageBuffer Bits;
 
     public void Clear()
     {
-        Mem.Clear(Bits.Span);
+        Mem.Clear(Bits);
         PeerConnectStatus[..].Clear();
         StartFrame = Frame.Zero;
         DisconnectRequested = false;
@@ -62,7 +42,7 @@ public readonly void Serialize(BinarySpanWriter writer)
         writer.Write(in InputSize);
         writer.Write(in NumBits);
         var bitCount = (int)Math.Ceiling(NumBits / (float)ByteSize.ByteToBits);
-        writer.Write(Bits.Span[..bitCount]);
+        writer.Write(Bits[..bitCount]);
     }
 
     public void Deserialize(BinarySpanReader reader)
@@ -76,11 +56,7 @@ public void Deserialize(BinarySpanReader reader)
         InputSize = reader.ReadByte();
         NumBits = reader.ReadUShort();
         var bitCount = (int)Math.Ceiling(NumBits / (float)ByteSize.ByteToBits);
-
-        if (Bits.Length is 0)
-            InitBits();
-
-        reader.ReadByte(Bits.Span[..bitCount]);
+        reader.ReadByte(Bits[..bitCount]);
     }
 
     public readonly bool TryFormat(
@@ -94,28 +70,6 @@ public readonly bool TryFormat(
         if (!writer.Write(NumBits)) return false;
         return true;
     }
-
-    public readonly bool Equals(InputMessage other) =>
-        PeerConnectStatus[..].SequenceEqual(other.PeerConnectStatus) &&
-        StartFrame.Equals(other.StartFrame) &&
-        DisconnectRequested == other.DisconnectRequested &&
-        AckFrame.Equals(other.AckFrame) && NumBits == other.NumBits &&
-        InputSize == other.InputSize &&
-        Mem.EqualBytes(InputBytes().Span, other.InputBytes().Span, truncate: true);
-
-    public override readonly bool Equals(object? obj) => obj is InputMessage other && Equals(other);
-
-    public override readonly int GetHashCode() => HashCode.Combine(
-        PeerConnectStatus, StartFrame, DisconnectRequested, AckFrame, NumBits, InputSize, Bits);
-
-    public readonly void Dispose()
-    {
-        if (Bits.Length > 0 && MemoryMarshal.ToEnumerable<byte>(Bits) is byte[] array)
-            ArrayPool<byte>.Shared.Return(array);
-    }
-
-    public static bool operator ==(InputMessage left, InputMessage right) => left.Equals(right);
-    public static bool operator !=(InputMessage left, InputMessage right) => !left.Equals(right);
 }
 
 [Serializable, InlineArray(Max.NumberOfPlayers)]
@@ -149,3 +103,11 @@ public override readonly string ToString()
         return builder.ToString();
     }
 }
+
+[Serializable, InlineArray(Max.CompressedBytes)]
+struct InputMessageBuffer
+{
+    byte element0;
+    public InputMessageBuffer(ReadOnlySpan<byte> bits) => bits.CopyTo(this);
+    public override readonly string ToString() => Mem.GetBitString(this);
+}

src/Backdash/Network/Messages/ProtocolMessage.cs

@@ -6,8 +6,7 @@
 namespace Backdash.Network.Messages;
 
 [StructLayout(LayoutKind.Explicit, Pack = 2)]
-struct ProtocolMessage(MessageType type)
-    : IDisposable, IBinarySerializable, IEquatable<ProtocolMessage>, IUtf8SpanFormattable
+struct ProtocolMessage(MessageType type) : IBinarySerializable, IEquatable<ProtocolMessage>, IUtf8SpanFormattable
 {
     [FieldOffset(0)]
     public Header Header = new(type);
@@ -30,7 +29,7 @@ struct ProtocolMessage(MessageType type)
     [FieldOffset(Header.Size)]
     public KeepAlive KeepAlive;
 
-    [FieldOffset(Header.Size + 2)]
+    [FieldOffset(Header.Size)]
     public InputMessage Input;
 
     public readonly void Serialize(BinarySpanWriter writer)
@@ -115,12 +114,6 @@ public override readonly string ToString()
         return $"Msg({Header.Type}){info}";
     }
 
-    public readonly void Dispose()
-    {
-        if (Header.Type is MessageType.Input)
-            Input.Dispose();
-    }
-
     public readonly bool TryFormat(
         Span<byte> utf8Destination, out int bytesWritten,
         ReadOnlySpan<char> format, IFormatProvider? provider

src/Backdash/Network/Protocol/Comm/InputEncoder.cs

@@ -5,9 +5,9 @@ namespace Backdash.Network.Protocol.Comm;
 
 static class InputEncoder
 {
-    public static DeltaXorRle.Encoder GetCompressor(in InputMessage inputMsg, Span<byte> lastBuffer) =>
-        new(inputMsg.Bits.Span, lastBuffer);
+    public static DeltaXorRle.Encoder GetCompressor(ref InputMessage inputMsg, Span<byte> lastBuffer) =>
+        new(inputMsg.Bits, lastBuffer);
 
-    public static DeltaXorRle.Decoder GetDecompressor(in InputMessage inputMsg) =>
-        new(inputMsg.Bits.Span, inputMsg.NumBits);
+    public static DeltaXorRle.Decoder GetDecompressor(ref InputMessage inputMsg) =>
+        new(inputMsg.Bits, inputMsg.NumBits);
 }