[feat]实现缓冲读取器BufferedReader，替代BufferedStream。因为BufferedStream内部从堆上分配8192字节内存数组，每一次Redis请求都需要分配一次，带来了大量内存分配和GC成本。

NewLife.Redis/Buffers/BufferedReader.cs

@@ -0,0 +1,146 @@
+using NewLife.Data;
+
+namespace NewLife.Caching.Buffers;
+
+/// <summary>缓存的读取器</summary>
+public ref struct BufferedReader
+{
+    #region 属性
+    private ReadOnlySpan<Byte> _span;
+    /// <summary>数据片段</summary>
+    public ReadOnlySpan<Byte> Span => _span;
+
+    private Int32 _index;
+    /// <summary>已读取字节数</summary>
+    public Int32 Position { get => _index; set => _index = value; }
+
+    /// <summary>总容量</summary>
+    public Int32 Capacity => _span.Length;
+
+    /// <summary>空闲容量</summary>
+    public Int32 FreeCapacity => _span.Length - _index;
+
+    private readonly Stream _stream;
+    private readonly Int32 _bufferSize;
+    private IPacket _data;
+    #endregion
+
+    #region 构造
+    /// <summary>实例化Span读取器</summary>
+    /// <param name="stream"></param>
+    /// <param name="data"></param>
+    /// <param name="bufferSize"></param>
+    public BufferedReader(Stream stream, IPacket data, Int32 bufferSize = 8192)
+    {
+        _stream = stream;
+        _bufferSize = bufferSize;
+        _data = data;
+        _span = data.GetSpan();
+    }
+    #endregion
+
+    #region 基础方法
+    /// <summary>告知有多少数据已从缓冲区读取</summary>
+    /// <param name="count"></param>
+    public void Advance(Int32 count)
+    {
+        if (count < 0) throw new ArgumentOutOfRangeException(nameof(count));
+        if (_index + count > _span.Length) throw new ArgumentOutOfRangeException(nameof(count));
+
+        _index += count;
+    }
+
+    /// <summary>返回要写入到的Span，其大小按 sizeHint 参数指定至少为所请求的大小</summary>
+    /// <param name="sizeHint"></param>
+    /// <returns></returns>
+    /// <exception cref="ArgumentOutOfRangeException"></exception>
+    public ReadOnlySpan<Byte> GetSpan(Int32 sizeHint = 0)
+    {
+        if (sizeHint > FreeCapacity) throw new ArgumentOutOfRangeException(nameof(sizeHint));
+
+        return _span[_index..];
+    }
+    #endregion
+
+    #region 读取方法
+    /// <summary>确保缓冲区中有足够的空间。</summary>
+    /// <param name="size">需要的字节数。</param>
+    /// <exception cref="InvalidOperationException"></exception>
+    public void EnsureSpace(Int32 size)
+    {
+        // 检查剩余空间大小，不足时，再从数据流中读取。此时需要注意，创建新的OwnerPacket后，需要先把之前剩余的一点数据拷贝过去，然后再读取Stream
+        var remain = FreeCapacity;
+        if (remain < size)
+        {
+            var idx = 0;
+            var pk = new OwnerPacket(_bufferSize);
+            if (_data != null && remain > 0)
+            {
+                if (!_data.TryGetArray(out var arr)) throw new NotSupportedException();
+
+                arr.AsSpan(_index, remain).CopyTo(pk.Buffer);
+                idx += remain;
+            }
+
+            _data.TryDispose();
+            _data = pk;
+            _index = 0;
+
+            // 多次读取，直到满足需求
+            //var n = _stream.ReadExactly(pk.Buffer, pk.Offset + idx, pk.Length - idx);
+            while (idx < size)
+            {
+                var n = _stream.Read(pk.Buffer, pk.Offset + idx, pk.Length - idx);
+                if (n < 0) break;
+
+                idx += n;
+            }
+            if (idx < size)
+                throw new InvalidOperationException("Not enough data to read.");
+            pk.Resize(idx);
+
+            _span = pk.GetSpan();
+        }
+
+        if (_index + size > _span.Length)
+            throw new InvalidOperationException("Not enough data to read.");
+    }
+
+    /// <summary>读取单个字节</summary>
+    /// <returns></returns>
+    public Byte ReadByte()
+    {
+        var size = sizeof(Byte);
+        EnsureSpace(size);
+
+        var result = _span[_index];
+        _index += size;
+        return result;
+    }
+
+    /// <summary>读取字节数组</summary>
+    /// <param name="length"></param>
+    /// <returns></returns>
+    /// <exception cref="InvalidOperationException"></exception>
+    public ReadOnlySpan<Byte> ReadBytes(Int32 length)
+    {
+        EnsureSpace(length);
+
+        var result = _span.Slice(_index, length);
+        _index += length;
+        return result;
+    }
+
+    /// <summary>读取数据包</summary>
+    /// <param name="length"></param>
+    /// <returns></returns>
+    public IPacket ReadPacket(Int32 length)
+    {
+        EnsureSpace(length);
+
+        var result = _data.Slice(_index, length);
+        _index += length;
+        return result;
+    }
+    #endregion
+}

NewLife.Redis/RedisClient.cs

@@ -7,6 +7,7 @@ using System.Security.Authentication;
 using System.Security.Cryptography.X509Certificates;
 using System.Text;
 using NewLife.Buffers;
+using NewLife.Caching.Buffers;
 using NewLife.Collections;
 using NewLife.Data;
 using NewLife.Log;
@@ -309,24 +310,19 @@ public class RedisClient : DisposeBase
     /// <returns></returns>
     protected virtual IList<Object?> GetResponse(Stream ns, Int32 count)
     {
-        var ms = new BufferedStream(ns);
+        //var ms = new BufferedStream(ns);
+        var ms = ns;
 
-        Char header;
+        using var pk = new OwnerPacket(MAX_POOL_SIZE);
-        var buf = Pool.Shared.Rent(1);
-        try
-        {
-            // 取巧进行异步操作，只要异步读取到第一个字节，后续同步读取
-            var n = ms.Read(buf, 0, 1);
-            if (n <= 0) return [];
 
-            header = (Char)buf[0];
+        var n = ms.Read(pk.Buffer, pk.Offset, pk.Length);
-        }
+        if (n <= 0) return [];
-        finally
-        {
-            Pool.Shared.Return(buf);
-        }
 
-        return ParseResponse(ms, count, header);
+        pk.Resize(n);
+
+        var reader = new BufferedReader(ms, pk, 8192);
+
+        return ParseResponse(ms, count, ref reader);
     }
 
     /// <summary>异步接收响应</summary>
@@ -336,27 +332,23 @@ public class RedisClient : DisposeBase
     /// <returns></returns>
     protected virtual async Task<IList<Object?>> GetResponseAsync(Stream ns, Int32 count, CancellationToken cancellationToken = default)
     {
-        Char header;
+        var ms = ns;
-        var buf = Pool.Shared.Rent(1);
+        using var pk = new OwnerPacket(MAX_POOL_SIZE);
-        try
-        {
-            // 取巧进行异步操作，只要异步读取到第一个字节，后续同步读取
-            if (cancellationToken == CancellationToken.None)
-                cancellationToken = new CancellationTokenSource(Timeout > 0 ? Timeout : Host.Timeout).Token;
-            var n = await ns.ReadAsync(buf, 0, 1, cancellationToken).ConfigureAwait(false);
-            if (n <= 0) return [];
 
-            header = (Char)buf[0];
+        // 取巧进行异步操作，只要异步读取到第一个字节，后续同步读取
-        }
+        if (cancellationToken == CancellationToken.None)
-        finally
+            cancellationToken = new CancellationTokenSource(Timeout > 0 ? Timeout : Host.Timeout).Token;
-        {
+        var n = await ns.ReadAsync(pk.Buffer, pk.Offset, pk.Length, cancellationToken).ConfigureAwait(false);
-            Pool.Shared.Return(buf);
+        if (n <= 0) return [];
-        }
 
-        return ParseResponse(ns, count, header);
+        pk.Resize(n);
+
+        var reader = new BufferedReader(ms, pk, 8192);
+
+        return ParseResponse(ms, count, ref reader);
     }
 
-    private IList<Object?> ParseResponse(Stream ms, Int32 count, Char header)
+    private IList<Object?> ParseResponse(Stream ms, Int32 count, ref BufferedReader reader)
     {
         /*
          * 响应格式
@@ -370,31 +362,28 @@ public class RedisClient : DisposeBase
         var list = new List<Object?>();
         var log = Log == null || Log == Logger.Null ? null : Pool.StringBuilder.Get();
 
+        //var reader = new SpanReader(pk.GetSpan());
+        var header = (Char)reader.ReadByte();
+
         // 多行响应
         for (var i = 0; i < count; i++)
         {
             // 解析响应
-            if (i > 0)
+            if (i > 0) header = (Char)reader.ReadByte();
-            {
-                var b = ms.ReadByte();
-                if (b == -1) break;
-
-                header = (Char)b;
-            }
 
             log?.Append(header);
             if (header == '$')
             {
-                list.Add(ReadBlock(ms, log));
+                list.Add(ReadBlock(ref reader, log));
             }
             else if (header == '*')
             {
-                list.Add(ReadBlocks(ms, log));
+                list.Add(ReadBlocks(ref reader, log));
             }
             else
             {
                 // 字符串以换行为结束符
-                var str = ReadLine(ms);
+                var str = ReadLine(ref reader);
                 log?.Append(str);
 
                 if (header is '+' or ':')
@@ -544,95 +533,68 @@ public class RedisClient : DisposeBase
         }
     }
 
-    private static IPacket? ReadBlock(Stream ms, StringBuilder? log) => ReadPacket(ms, log);
+    private static IPacket? ReadBlock(ref BufferedReader reader, StringBuilder? log) => ReadPacket(ref reader, log);
 
-    private Object?[] ReadBlocks(Stream ms, StringBuilder? log)
+    private Object?[] ReadBlocks(ref BufferedReader reader, StringBuilder? log)
     {
         // 结果集数量
-        var len = ReadLength(ms);
+        var len = ReadLength(ref reader);
         log?.Append(len);
         if (len < 0) return [];
 
         var arr = new Object?[len];
         for (var i = 0; i < len; i++)
         {
-            var b = ms.ReadByte();
+            var header = (Char)reader.ReadByte();
-            if (b == -1) break;
-
-            var header = (Char)b;
             log?.Append(' ');
             log?.Append(header);
             if (header == '$')
             {
-                arr[i] = ReadPacket(ms, log);
+                arr[i] = ReadPacket(ref reader, log);
             }
             else if (header is '+' or ':')
             {
-                arr[i] = ReadLine(ms);
+                arr[i] = ReadLine(ref reader);
                 log?.Append(arr[i]);
             }
             else if (header == '*')
             {
-                arr[i] = ReadBlocks(ms, log);
+                arr[i] = ReadBlocks(ref reader, log);
             }
         }
 
         return arr;
     }
 
-    private static IPacket? ReadPacket(Stream ms, StringBuilder? log)
+    private static IPacket? ReadPacket(ref BufferedReader reader, StringBuilder? log)
     {
-        var len = ReadLength(ms);
+        var len = ReadLength(ref reader);
         log?.Append(len);
         if (len == 0)
         {
             // 某些字段即使长度是0，还是要把换行符读走
-            ReadLine(ms);
+            ReadLine(ref reader);
             return null;
         }
         if (len <= 0) return null;
         len += 2;
 
-        //// 很多时候，数据长度为1，特殊优化
+        // 读取数据包，并跳过换行符
-        //if (len == 3)
+        var pk = reader.ReadPacket(len - 2);
-        //{
+        reader.Advance(2);
-        //    var rs = ms.ReadByte();
+        return pk;
-        //    // 再读取两个换行符，网络流不支持Seek
-        //    //ms.Seek(2, SeekOrigin.Current);
-        //    ms.ReadByte();
-        //    ms.ReadByte();
-        //    return rs;
-        //}
-
-        // 从内存池借出，包装到MemorySegment中，一路向上传递，用完后Dispose还到池里
-        var owner = new OwnerPacket(len);
-        var span = owner.GetSpan();
-
-        var p = 0;
-        while (p < len)
-        {
-            // 等待，直到读完需要的数据，避免大包丢数据
-            var count = ms.Read(span.Slice(p, len - p));
-            if (count <= 0) break;
-
-            p += count;
-        }
-
-        return owner.Slice(0, p - 2);
     }
 
-    private static String ReadLine(Stream ms)
+    private static String ReadLine(ref BufferedReader reader)
     {
         var sb = Pool.StringBuilder.Get();
-        while (true)
+        var count = reader.FreeCapacity;
+        for (var i = 0; i < count; i++)
         {
-            var b = ms.ReadByte();
+            var b = (Char)reader.ReadByte();
-            if (b < 0) break;
+            if (b == '\r' && i + 1 < count)
-
-            if (b == '\r')
             {
-                var b2 = ms.ReadByte();
+                var b2 = (Char)reader.ReadByte();
-                if (b2 < 0) break;
                 if (b2 == '\n') break;
 
                 sb.Append((Char)b);
@@ -645,19 +607,17 @@ public class RedisClient : DisposeBase
         return sb.Return(true);
     }
 
-    private static Int32 ReadLength(Stream ms)
+    private static Int32 ReadLength(ref BufferedReader reader)
     {
         Span<Char> span = stackalloc Char[32];
         var k = 0;
-        while (true)
+        var count = reader.FreeCapacity;
+        for (var i = 0; i < count; i++)
         {
-            var b = ms.ReadByte();
+            var b = (Char)reader.ReadByte();
-            if (b < 0) break;
+            if (b == '\r' && i + 1 < count)
-
-            if (b == '\r')
             {
-                var b2 = ms.ReadByte();
+                var b2 = (Char)reader.ReadByte();
-                if (b2 < 0) break;
                 if (b2 == '\n') break;
 
                 span[k++] = (Char)b;
@@ -728,7 +688,12 @@ public class RedisClient : DisposeBase
             var rs = ExecuteCommand(cmd, args);
             if (rs == null) return default;
             if (rs is TResult rs2) return rs2;
-            if (TryChangeType(rs, typeof(TResult), out var target)) return (TResult?)target;
+            if (TryChangeType(rs, typeof(TResult), out var target))
+            {
+                // 释放内部申请的OwnerPacket
+                rs.TryDispose();
+                return (TResult?)target;
+            }
 
             return default;
         }
@@ -762,6 +727,8 @@ public class RedisClient : DisposeBase
             if (rs == null) return false;
             if (TryChangeType(rs, typeof(TResult), out var target))
             {
+                // 释放内部申请的OwnerPacket
+                rs.TryDispose();
                 value = (TResult?)target;
                 return true;
             }
@@ -819,7 +786,12 @@ public class RedisClient : DisposeBase
         var rs = await ExecuteAsync(cmd, args, cancellationToken).ConfigureAwait(false);
         if (rs == null) return default;
         if (rs is TResult rs2) return rs2;
-        if (TryChangeType(rs, typeof(TResult), out var target)) return (TResult?)target;
+        if (TryChangeType(rs, typeof(TResult), out var target))
+        {
+            // 释放内部申请的OwnerPacket
+            rs.TryDispose();
+            return (TResult?)target;
+        }
 
         return default;
     }
@@ -965,7 +937,12 @@ public class RedisClient : DisposeBase
             for (var i = 0; i < list.Count; i++)
             {
                 var rs = list[i];
-                if (rs != null && TryChangeType(rs, ps[i].Type, out var target) && target != null) list[i] = target;
+                if (rs != null && TryChangeType(rs, ps[i].Type, out var target) && target != null)
+                {
+                    // 释放内部申请的OwnerPacket
+                    rs.TryDispose();
+                    list[i] = target;
+                }
             }
 
             return list.ToArray();

Samples/Benchmark/BasicBenchmark.cs

@@ -12,6 +12,7 @@ public class BasicBenchmark
 {
     public FullRedis Redis { get; set; }
 
+    private String _key;
     private String[] _keys;
 
     [GlobalSetup]
@@ -26,12 +27,29 @@ public class BasicBenchmark
 
         Redis = rds;
 
+        _key = Rand.NextString(16);
         var ks = new String[100_000];
         for (var i = 0; i < ks.Length; i++)
         {
             ks[i] = Rand.NextString(16);
         }
         _keys = ks;
+
+        rds.Set(_key, _key);
+        var v = rds.Get<String>(_key);
+        rds.Remove(_key);
+    }
+
+    [Benchmark]
+    public void SetTest()
+    {
+        var rds = Redis;
+        var value = Rand.NextString(16);
+
+        for (var i = 0; i < _keys.Length; i++)
+        {
+            rds.Set(_keys[i], value);
+        }
     }
 
     [Benchmark]
@@ -46,14 +64,13 @@ public class BasicBenchmark
     }
 
     [Benchmark]
-    public void SetTest()
+    public void RemoveTest()
     {
         var rds = Redis;
-        var value = Rand.NextString(16);
 
         for (var i = 0; i < _keys.Length; i++)
         {
-            rds.Set(_keys[i], value);
+            rds.Remove(_keys[i]);
         }
     }
 }