[feat]新增Gen2GcCallback，配合轻量级内存池，在GC2时完全释放池中对象。

NewLife.Core/Caching/Cache.cs

@@ -376,13 +376,11 @@ public virtual Int64 Bench(Boolean rand = false, Int32 batch = 0)
         var times = GetTimesPerThread(rand, batch);
 
         // 提前准备Keys，减少性能测试中的干扰
-        var key = "bstr_";
-        //var key2 = "bint_";
+        var key = "b_";
         var max = cpu > 64 ? cpu : 64;
         var maxTimes = times * max;
         if (!rand) maxTimes = max;
         _keys = new String[maxTimes];
-        //_keys2 = new String[maxTimes];
 
         var sb = new StringBuilder();
         for (var i = 0; i < _keys.Length; i++)
@@ -391,11 +389,6 @@ public virtual Int64 Bench(Boolean rand = false, Int32 batch = 0)
             sb.Append(key);
             sb.Append(i);
             _keys[i] = sb.ToString();
-
-            //sb.Clear();
-            //sb.Append(key2);
-            //sb.Append(i);
-            //_keys2[i] = sb.ToString();
         }
 
         // 单线程

NewLife.Core/Collections/IPool.cs

@@ -19,6 +19,7 @@ public interface IPool<T>
 
     /// <summary>归还</summary>
     /// <param name="value"></param>
+    [Obsolete("Please use Return from 2024-02-01")]
     Boolean Put(T value);
 
     /// <summary>归还</summary>
@@ -35,9 +36,6 @@ public interface IPool<T>
 /// </remarks>
 public static class Pool
 {
-    #region 扩展
-    #endregion
-
     #region StringBuilder
     /// <summary>字符串构建器池</summary>
     public static IPool<StringBuilder> StringBuilder { get; set; } = new StringBuilderPool();
@@ -53,7 +51,7 @@ public static String Put(this StringBuilder sb, Boolean requireResult = false)
 
         var str = requireResult ? sb.ToString() : String.Empty;
 
-        Pool.StringBuilder.Put(sb);
+        Pool.StringBuilder.Return(sb);
 
         return str;
     }
@@ -68,7 +66,7 @@ public static String Return(this StringBuilder sb, Boolean returnResult = true)
 
         var str = returnResult ? sb.ToString() : String.Empty;
 
-        Pool.StringBuilder.Put(sb);
+        Pool.StringBuilder.Return(sb);
 
         return str;
     }
@@ -82,22 +80,13 @@ public class StringBuilderPool : Pool<StringBuilder>
         /// <summary>最大容量。超过该大小时不进入池内，默认4k</summary>
         public Int32 MaximumCapacity { get; set; } = 4 * 1024;
 
+        /// <summary>实例化字符串池。GC2时回收</summary>
+        public StringBuilderPool() : base(0, true) { }
+
         /// <summary>创建</summary>
         /// <returns></returns>
         protected override StringBuilder OnCreate() => new(InitialCapacity);
 
-        /// <summary>归还</summary>
-        /// <param name="value"></param>
-        /// <returns></returns>
-        public override Boolean Put(StringBuilder value)
-        {
-            if (value.Capacity > MaximumCapacity) return false;
-
-            value.Clear();
-
-            return base.Put(value);
-        }
-
         /// <summary>归还</summary>
         /// <param name="value"></param>
         /// <returns></returns>
@@ -121,16 +110,7 @@ public override Boolean Return(StringBuilder value)
     /// <param name="requireResult">是否需要返回结果</param>
     /// <returns></returns>
     [Obsolete("Please use Return from 2024-02-01")]
-    public static Byte[] Put(this MemoryStream ms, Boolean requireResult = false)
-    {
-        //if (ms == null) return null;
-
-        var buf = requireResult ? ms.ToArray() : Empty;
-
-        Pool.MemoryStream.Put(ms);
-
-        return buf;
-    }
+    public static Byte[] Put(this MemoryStream ms, Boolean requireResult = false) => Return(ms, requireResult);
 
     /// <summary>归还一个内存流到对象池</summary>
     /// <param name="ms"></param>
@@ -142,7 +122,7 @@ public static Byte[] Return(this MemoryStream ms, Boolean returnResult = true)
 
         var buf = returnResult ? ms.ToArray() : Empty;
 
-        Pool.MemoryStream.Put(ms);
+        Pool.MemoryStream.Return(ms);
 
         return buf;
     }
@@ -156,23 +136,13 @@ public class MemoryStreamPool : Pool<MemoryStream>
         /// <summary>最大容量。超过该大小时不进入池内，默认64k</summary>
         public Int32 MaximumCapacity { get; set; } = 64 * 1024;
 
+        /// <summary>实例化字符串池。GC2时回收</summary>
+        public MemoryStreamPool() : base(0, true) { }
+
         /// <summary>创建</summary>
         /// <returns></returns>
         protected override MemoryStream OnCreate() => new(InitialCapacity);
 
-        /// <summary>归还</summary>
-        /// <param name="value"></param>
-        /// <returns></returns>
-        public override Boolean Put(MemoryStream value)
-        {
-            if (value.Capacity > MaximumCapacity) return false;
-
-            value.Position = 0;
-            value.SetLength(0);
-
-            return base.Put(value);
-        }
-
         /// <summary>归还</summary>
         /// <param name="value"></param>
         /// <returns></returns>
@@ -191,7 +161,7 @@ public override Boolean Return(MemoryStream value)
     #region ByteArray
     /// <summary>字节数组共享存储</summary>
     public static ArrayPool<Byte> Shared { get; set; } = ArrayPool<Byte>.Shared;
-   
+
     /// <summary>空数组</summary>
     public static Byte[] Empty { get; } = [];
     #endregion

NewLife.Core/Collections/ObjectPool.cs

@@ -183,59 +183,8 @@ public virtual T Get()
 
     /// <summary>归还</summary>
     /// <param name="value"></param>
-    public virtual Boolean Put(T value)
-    {
-        if (value == null) return false;
-
-        // 从繁忙队列找到并移除缓存项
-        if (!_busy.TryRemove(value, out var pi))
-        {
-#if DEBUG
-            WriteLog("Put Error");
-#endif
-            Interlocked.Increment(ref _ReleaseCount);
-
-            return false;
-        }
-
-        Interlocked.Decrement(ref _BusyCount);
-
-        // 是否可用
-        if (!OnPut(value))
-        {
-            Interlocked.Increment(ref _ReleaseCount);
-            return false;
-        }
-
-        if (value is DisposeBase db && db.Disposed)
-        {
-            Interlocked.Increment(ref _ReleaseCount);
-            return false;
-        }
-
-        var min = Min;
-
-        // 如果空闲数不足最小值，则返回到基础空闲集合
-        if (_FreeCount < min /*|| _free.Count < min*/)
-            _free.Push(pi);
-        else
-            _free2.Enqueue(pi);
-
-        // 最后时间
-        pi.LastTime = TimerX.Now;
-
-        Interlocked.Increment(ref _FreeCount);
-
-        // 启动定期清理的定时器
-        StartTimer();
-
-        return true;
-    }
-
-    /// <summary>归还时是否可用</summary>
-    /// <param name="value"></param>
-    /// <returns></returns>
-    protected virtual Boolean OnPut(T value) => true;
+    [Obsolete("Please use Return from 2024-02-01")]
+    public virtual Boolean Put(T value) => Return(value);
 
     /// <summary>归还</summary>
     /// <param name="value"></param>
@@ -247,7 +196,7 @@ public virtual Boolean Return(T value)
         if (!_busy.TryRemove(value, out var pi))
         {
 #if DEBUG
-            WriteLog("Put Error");
+            WriteLog("Return Error");
 #endif
             Interlocked.Increment(ref _ReleaseCount);
 
@@ -483,7 +432,7 @@ protected override void Dispose(Boolean disposing)
     {
         base.Dispose(disposing);
 
-        Pool.Put(Value);
+        Pool.Return(Value);
     }
     #endregion
 }

NewLife.Core/Collections/Pool.cs

@@ -27,14 +27,37 @@ struct Item
 
     #region 构造
     /// <summary>实例化对象池。默认大小CPU*2</summary>
-    /// <param name="max"></param>
+    /// <param name="max">最大对象数。默认大小CPU*2</param>
     public Pool(Int32 max = 0)
     {
         if (max <= 0) max = Environment.ProcessorCount * 2;
 
         Max = max;
     }
 
+    /// <summary>实例化对象池。GC2时回收</summary>
+    /// <param name="max">最大对象数。默认大小CPU*2</param>
+    /// <param name="useGcClear">是否在二代GC时回收池里对象</param>
+    protected Pool(Int32 max, Boolean useGcClear) : this(max)
+    {
+        if (useGcClear) Gen2GcCallback.Register(s => (s as Pool<T>)!.OnGen2(), this);
+    }
+
+    private Int64 _next;
+    private Boolean OnGen2()
+    {
+        var now = Runtime.TickCount64;
+        if (_next <= 0)
+            _next = now + 60000;
+        else if (_next < now)
+        {
+            Clear();
+            _next = now + 60000;
+        }
+
+        return true;
+    }
+
     [MemberNotNull(nameof(_items))]
     private void Init()
     {
@@ -75,21 +98,8 @@ public virtual T Get()
     /// <summary>归还</summary>
     /// <param name="value"></param>
     /// <returns></returns>
-    public virtual Boolean Put(T value)
-    {
-        // 最热的一个对象在外层，便于快速存取
-        if (_current == null && Interlocked.CompareExchange(ref _current, value, null) == null) return true;
-
-        Init();
-
-        var items = _items;
-        for (var i = 0; i < items.Length; ++i)
-        {
-            if (Interlocked.CompareExchange(ref items[i].Value, value, null) == null) return true;
-        }
-
-        return false;
-    }
+    [Obsolete("Please use Return from 2024-02-01")]
+    public virtual Boolean Put(T value) => Return(value);
 
     /// <summary>归还</summary>
     /// <param name="value"></param>

NewLife.Core/Common/Gen2GcCallback.cs

@@ -0,0 +1,77 @@
+using System.ComponentModel;
+using System.Runtime.ConstrainedExecution;
+using System.Runtime.InteropServices;
+
+namespace NewLife;
+
+/// <summary>Gen2垃圾回收回调</summary>
+[EditorBrowsable(EditorBrowsableState.Never)]
+public class Gen2GcCallback : CriticalFinalizerObject
+{
+    private readonly Func<Boolean> _callback0;
+
+    private readonly Func<Object, Boolean> _callback1;
+
+    private GCHandle _weakTargetObj;
+
+    private Gen2GcCallback(Func<Boolean> callback) => _callback0 = callback;
+
+    private Gen2GcCallback(Func<Object, Boolean> callback, Object targetObj)
+    {
+        _callback1 = callback;
+        _weakTargetObj = GCHandle.Alloc(targetObj, GCHandleType.Weak);
+    }
+
+    /// <summary>
+    /// Registers a callback to be invoked during Gen2 garbage collection.
+    /// </summary>
+    /// <param name="callback">The callback function to be invoked.</param>
+    public static void Register(Func<Boolean> callback)
+    {
+        new Gen2GcCallback(callback);
+    }
+
+    /// <summary>
+    /// Registers a callback to be invoked during Gen2 garbage collection with a target object.
+    /// </summary>
+    /// <param name="callback">The callback function to be invoked.</param>
+    /// <param name="targetObj">The target object associated with the callback.</param>
+    public static void Register(Func<Object, Boolean> callback, Object targetObj)
+    {
+        new Gen2GcCallback(callback, targetObj);
+    }
+
+    ~Gen2GcCallback()
+    {
+        if (_weakTargetObj.IsAllocated)
+        {
+            var target = _weakTargetObj.Target;
+            if (target == null)
+            {
+                _weakTargetObj.Free();
+                return;
+            }
+            try
+            {
+                if (!_callback1(target))
+                {
+                    _weakTargetObj.Free();
+                    return;
+                }
+            }
+            catch { }
+        }
+        else
+        {
+            try
+            {
+                if (!_callback0())
+                {
+                    return;
+                }
+            }
+            catch { }
+        }
+        GC.ReRegisterForFinalize(this);
+    }
+}