对于byte[]，安全比较与不安全比较

我在不同的地方读过，关于使用固定块的数组之间的不安全迭代有多快。我已经在。net 4和。4.5中尝试过，获得了或多或少相同的结果。
安全比较总是更快，有时快一点，有时快一半，特别是在。net 4中。

我做错了什么吗?

class Program
{
    public unsafe static int UnsafeCompareTo2(byte[] self, byte[] other)
    {
        if (self.Length < other.Length) { return -1; }
        if (self.Length > other.Length) { return +1; }
        GCHandle selfHandle =
            GCHandle.Alloc(self, GCHandleType.Pinned);
        GCHandle otherHandle =
            GCHandle.Alloc(other, GCHandleType.Pinned);
        byte* selfPtr = (byte*)
            selfHandle.AddrOfPinnedObject().ToPointer();
        byte* otherPtr = (byte*)
            otherHandle.AddrOfPinnedObject().ToPointer();
        int length = self.Length;
        int comparison = 0;
        for (int index = 0; index < length; index++)
        {
            comparison =
                (*selfPtr++).CompareTo((*otherPtr++));
            if (comparison != 0) { break; }
        }
        selfHandle.Free();
        return comparison;
    }
    public static int CompareTo(byte[] self, byte[] other)
    {
        if (self.Length < other.Length) { return -1; }
        if (self.Length > other.Length) { return +1; }
        int comparison = 0;
        for (int i = 0; i < self.Length && i < other.Length; i++)
        {
            if ((comparison = self[i].CompareTo(other[i])) != 0)
            { return comparison; }
        }
        return comparison;
    }
    public unsafe static int UnsafeCompareTo(byte[] self, byte[] other)
    {
        if (self.Length < other.Length) { return -1; }
        if (self.Length > other.Length) { return +1; }
        int n = self.Length;
        fixed (byte* selfPtr = self, otherPtr = other)
        {
            byte* ptr1 = selfPtr;
            byte* ptr2 = otherPtr;
            while (n-- > 0)
            {
                int comparison;
                if ((comparison = (*ptr1++).CompareTo(*ptr2++)) != 0)
                {
                    return comparison;
                }
            }   
        }
        return 0;
    }
    static void Main(string[] args)
    {
        byte[] b1 = { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20 };
        byte[] b2 = { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 21 };
        Stopwatch watch = new Stopwatch();
        watch.Start();
        int result;
        for(long i = 0; i < Math.Pow(10, 2); i++)
            result = CompareTo(b1, b2);
        watch.Stop();
        Console.WriteLine("safe = {0}", watch.Elapsed);
        watch.Restart();
        for (long i = 0; i < Math.Pow(10, 2); i++)
            result = UnsafeCompareTo(b1, b2);
        watch.Stop();
        Console.WriteLine("unsafe1 = {0}", watch.Elapsed);
        watch.Restart();
        for (long i = 0; i < Math.Pow(10, 2); i++)
            result = UnsafeCompareTo2(b1, b2);
        watch.Stop();
        Console.WriteLine("unsafe2 = {0}", watch.Elapsed);
        Console.ReadLine();
    }
}

public unsafe static int UnsafeCompareTo(byte[] self, byte[] other)
{
    if (self.Length < other.Length) { return -1; }
    if (self.Length > other.Length) { return +1; }
    int n = self.Length;
    fixed (byte* selfPtr = self, otherPtr = other)
    {
        byte* ptr1 = selfPtr;
        byte* ptr2 = otherPtr;
        byte b1;
        byte b2;
        while (n-- > 0)
        {
            b1 = (*ptr1++);
            b2 = (*ptr2++);
            if (b1 == b2)
                continue;
            return b1.CompareTo(b2);
        }
    }
    return 0;
}

GCHandle otherHandle = GCHandle.Alloc(self, GCHandleType.Pinned);