.NET Core中的对象池

该DOTNET芯具有添加到该基类库（BCL）对象池的实施方案。您可以在此处阅读原始的GitHub问题，并查看System.Buffers的代码。当前，

ArrayPool

namespace System.Buffers{    public abstract class ArrayPool<T>    {        public static ArrayPool<T> Shared { get; internal set; }        public static ArrayPool<T> Create(int maxBufferSize = <number>, int numberOfBuffers = <number>);        public T[] Rent(int size);        public T[] Enlarge(T[] buffer, int newSize, bool clearBuffer = false);        public void Return(T[] buffer, bool clearBuffer = false);    }}

在ASP.NET Core中可以看到其用法示例。因为它在dotnet核心BCL中，所以ASP.NET
Core可以与其他对象（例如Newtonsoft.Json的JSON序列化器）共享它的对象池。您可以阅读此博客文章，以获得有关Newtonsoft.Json如何执行此操作的更多信息。

Microsoft Roslyn C＃编译器中的对象池

新的Microsoft Roslyn
C＃编译器包含ObjectPool类型，该类型用于合并经常使用的对象，这些对象通常会被更新并非常频繁地收集垃圾。这减少了必须执行的垃圾收集操作的数量和大小。有几个不同的子实现都使用ObjectPool（请参阅：为什么在Roslyn中有这么多的对象池实现？）。

1-
SharedPools-存储20个对象的池，如果使用BigDefault，则存储100个对象。

// Example 1 - In a using statement, so the object gets freed at the end.using (PooledObject<Foo> pooledObject = SharedPools.Default<List<Foo>>().GetPooledObject()){    // Do something with pooledObject.Object}// Example 2 - No using statement so you need to be sure no exceptions are not thrown.List<Foo> list = SharedPools.Default<List<Foo>>().AllocateAndClear();// Do something with listSharedPools.Default<List<Foo>>().Free(list);// Example 3 - I have also seen this variation of the above pattern, which ends up the same as Example 1, except Example 1 seems to create a new instance of the IDisposable [PooledObject<T>][4] object. This is probably the preferred option if you want fewer GC's.List<Foo> list = SharedPools.Default<List<Foo>>().AllocateAndClear();try{    // Do something with list}finally{    SharedPools.Default<List<Foo>>().Free(list);}

2-
ListPool和StringBuilderPool-不是严格分开实现，而是围绕上面显示的SharedPools实现进行包装，专门用于List和StringBuilder。因此，这将重用存储在SharedPools中的对象池。

// Example 1 - No using statement so you need to be sure no exceptions are thrown.StringBuilder stringBuilder= StringBuilderPool.Allocate();// Do something with stringBuilderStringBuilderPool.Free(stringBuilder);// Example 2 - Safer version of Example 1.StringBuilder stringBuilder= StringBuilderPool.Allocate();try{    // Do something with stringBuilder}finally{    StringBuilderPool.Free(stringBuilder);}

3-
PooledDictionary和PooledHashSet-它们直接使用ObjectPool并具有完全独立的对象池。存储128个对象的池。

// Example 1PooledHashSet<Foo> hashSet = PooledHashSet<Foo>.GetInstance()// Do something with hashSet.hashSet.Free();// Example 2 - Safer version of Example 1.PooledHashSet<Foo> hashSet = PooledHashSet<Foo>.GetInstance()try{    // Do something with hashSet.}finally{    hashSet.Free();}

Microsoft.IO.RecyclableMemoryStream

该库提供

MemoryStream

System.IO.MemoryStream

var sourceBuffer = new byte[]{0,1,2,3,4,5,6,7}; var manager = new RecyclableMemoryStreamManager(); using (var stream = manager.GetStream()) {     stream.Write(sourceBuffer, 0, sourceBuffer.Length); }

注意，

RecyclableMemoryStreamManager