benchmark arrays

src/DotRecast.Core/Buffers/RcRentedArray.cs

@@ -6,7 +6,7 @@ namespace DotRecast.Core.Buffers
 {
     public static class RcRentedArray
     {
-        public static RcRentedArray<T> RentDisposableArray<T>(int minimumLength)
+        public static RcRentedArray<T> Rent<T>(int minimumLength)
         {
             var array = ArrayPool<T>.Shared.Rent(minimumLength);
             return new RcRentedArray<T>(ArrayPool<T>.Shared, array, minimumLength);
@@ -17,44 +17,41 @@ namespace DotRecast.Core.Buffers
     {
         private ArrayPool<T> _owner;
         private T[] _array;
-        private readonly RcAtomicInteger _disposed;
 
         public int Length { get; }
+        public bool IsDisposed => null == _owner || null == _array;
 
         internal RcRentedArray(ArrayPool<T> owner, T[] array, int length)
         {
             _owner = owner;
             _array = array;
             Length = length;
-            _disposed = new RcAtomicInteger(0);
         }
 
-        public T this[int index]
+        public ref T this[int index]
         {
             [MethodImpl(MethodImplOptions.AggressiveInlining)]
             get
             {
                 RcThrowHelper.ThrowExceptionIfIndexOutOfRange(index, Length);
-                return _array[index];
+                return ref _array[index];
             }
+        }
 
-            [MethodImpl(MethodImplOptions.AggressiveInlining)]
-            set
-            {
-                RcThrowHelper.ThrowExceptionIfIndexOutOfRange(index, Length);
-                _array[index] = value;
-            }
+        public T[] AsArray()
+        {
+            return _array;
         }
 
 
         public void Dispose()
         {
-            if (1 != _disposed.IncrementAndGet())
-                return;
-
-            _owner?.Return(_array, true);
-            _array = null;
-            _owner = null;
+            if (null != _owner && null != _array)
+            {
+                _owner.Return(_array, true);
+                _owner = null;
+                _array = null;
+            }
         }
     }
 }

test/DotRecast.Core.Test/RcArrayBenchmarkTests.cs

@@ -0,0 +1,101 @@
+using System;
+using System.Buffers;
+using System.Collections.Generic;
+using DotRecast.Core.Buffers;
+using DotRecast.Core.Collections;
+using NUnit.Framework;
+
+namespace DotRecast.Core.Test;
+
+public class RcArrayBenchmarkTests
+{
+    private const int StepLength = 512;
+    private const int RandomLoop = 1000;
+    private readonly RcRand _rand = new RcRand();
+
+    private (string title, long ticks) Bench(string title, Action<int> source)
+    {
+        var begin = RcFrequency.Ticks;
+        for (int step = StepLength; step > 0; --step)
+        {
+            for (int i = 0; i < RandomLoop; ++i)
+            {
+                source.Invoke(step);
+            }
+        }
+
+        var end = RcFrequency.Ticks - begin;
+        return (title, end);
+    }
+
+
+    private void RoundForArray(int len)
+    {
+        var array = new int[len];
+        for (int ii = 0; ii < len; ++ii)
+        {
+            array[ii] = _rand.NextInt32();
+        }
+    }
+
+
+    private void RoundForPureRentArray(int len)
+    {
+        var array = ArrayPool<int>.Shared.Rent(len);
+        for (int ii = 0; ii < array.Length; ++ii)
+        {
+            array[ii] = _rand.NextInt32();
+        }
+
+        ArrayPool<int>.Shared.Return(array);
+    }
+
+
+    private void RoundForRcRentedArray(int len)
+    {
+        using var rentedArray = RcRentedArray.Rent<int>(len);
+        var array = rentedArray.AsArray();
+        for (int i = 0; i < rentedArray.Length; ++i)
+        {
+            array[i] = _rand.NextInt32();
+        }
+    }
+
+
+    private void RoundForRcStackArray(int len)
+    {
+        var array = new RcStackArray512<int>();
+        for (int ii = 0; ii < len; ++ii)
+        {
+            array[ii] = _rand.NextInt32();
+        }
+    }
+
+    private void RoundForStackalloc(int len)
+    {
+        Span<int> array = stackalloc int[len];
+        for (int ii = 0; ii < len; ++ii)
+        {
+            array[ii] = _rand.NextInt32();
+        }
+    }
+
+
+    [Test]
+    public void TestBenchmarkArrays()
+    {
+        var list = new List<(string title, long ticks)>();
+        list.Add(Bench("new int[len]", RoundForArray));
+        list.Add(Bench("ArrayPool<int>.Shared.Rent(len)", RoundForPureRentArray));
+        list.Add(Bench("RcRentedArray.Rent<int>(len)", RoundForRcRentedArray));
+        list.Add(Bench("new RcStackArray512<int>()", RoundForRcStackArray));
+        list.Add(Bench("stackalloc int[len]", RoundForStackalloc));
+
+        list.Sort((x, y) => x.ticks.CompareTo(y.ticks));
+
+        foreach (var t in list)
+        {
+            Console.WriteLine($"{t.title} {t.ticks / (double)TimeSpan.TicksPerMillisecond} ms");
+        }
+    }
+}

test/DotRecast.Core.Test/RcRentedArrayTest.cs

@@ -31,7 +31,7 @@ public class RcRentedArrayTest
             {
                 int length = Math.Max(2, (int)(rand.Next() * 2048));
                 var values = RandomValues(length);
-                using var array = RcRentedArray.RentDisposableArray<int>(length);
+                using var array = RcRentedArray.Rent<int>(length);
 
                 for (int i = 0; i < array.Length; ++i)
                 {