public unsafe void BufferEx_Read_Managed_Perf()

in Sources/Runtime/Test.Psi/MemoryAccessPerf.cs [34:187]

• 127 lines of code
• 23 McCabe index (conditional complexity)

        public unsafe void BufferEx_Read_Managed_Perf()
        {
            var iterations = 100000;
            var count = 256;
            var bytes = new byte[count * 16];
            int value = 1;

            // warm-up
            BufferEx.SizeOf<int>();
            value = BufferEx.Read<int>(bytes, 0);

            var sw = Stopwatch.StartNew();
            for (var i = 0; i < iterations; i++)
            {
                for (int j = 0; j < count; j++)
                {
                    value = BufferEx.Read<int>(bytes, j);
                }
            }

            sw.Stop();
            Console.WriteLine("Read " + sw.ElapsedTicks);

            var items = new int[256];
            sw = Stopwatch.StartNew();
            for (var i = 0; i < iterations; i++)
            {
                for (int j = 0; j < count; j++)
                {
                    ReadBaseline(ref value, items, j);
                }
            }

            sw.Stop();
            Console.WriteLine("Read T from T[] baseline " + sw.ElapsedTicks);

            sw = Stopwatch.StartNew();
            for (var i = 0; i < iterations; i++)
            {
                for (int j = 0; j < count; j++)
                {
                    ReadBaseline(ref value, bytes, j);
                }
            }

            sw.Stop();
            Console.WriteLine("Read int baseline " + sw.ElapsedTicks);

            var ptr = System.Runtime.InteropServices.Marshal.AllocHGlobal(256 * 16);
            BufferEx.Read<int>(ptr);

            sw = Stopwatch.StartNew();
            for (var i = 0; i < iterations; i++)
            {
                for (int j = 0; j < count; j++)
                {
                    BufferEx.Read<int>(ptr + j);
                }
            }

            sw.Stop();
            Console.WriteLine("Read* " + sw.ElapsedTicks);

            sw = Stopwatch.StartNew();
            for (var i = 0; i < iterations; i++)
            {
                for (int j = 0; j < count; j++)
                {
                    ReadBaseline(ref value, ptr, j);
                }
            }

            sw.Stop();
            Console.WriteLine("Read* int baseline " + sw.ElapsedTicks);

            var rgbValue = default(RGB);
            BufferEx.Read<RGB>(bytes, 0);

            sw = Stopwatch.StartNew();
            for (var i = 0; i < iterations; i++)
            {
                for (int j = 0; j < count; j++)
                {
                    rgbValue = BufferEx.Read<RGB>(bytes, j);
                }
            }

            sw.Stop();
            Console.WriteLine("Read rgb " + sw.ElapsedTicks);

            BufferEx.Read<RGB>(bytes, 0);
            sw = Stopwatch.StartNew();
            for (var i = 0; i < iterations; i++)
            {
                for (int j = 0; j < count; j++)
                {
                    BufferEx.Read<RGB>(bytes, j);
                }
            }

            sw.Stop();
            Console.WriteLine("Read ret rgb " + sw.ElapsedTicks);

            BufferEx.Read<RGB>(ptr);

            sw = Stopwatch.StartNew();
            for (var i = 0; i < iterations; i++)
            {
                for (int j = 0; j < count; j++)
                {
                    BufferEx.Read<RGB>(ptr + j);
                }
            }

            sw.Stop();
            Console.WriteLine("Read* rgb" + sw.ElapsedTicks);

            sw = Stopwatch.StartNew();
            for (var i = 0; i < iterations; i++)
            {
                for (int j = 0; j < count; j++)
                {
                    ReadBaseline(ref rgbValue, bytes, j);
                }
            }

            sw.Stop();
            Console.WriteLine("Read rgb baseline " + sw.ElapsedTicks);

            sw = Stopwatch.StartNew();
            for (var i = 0; i < iterations; i++)
            {
                for (int j = 0; j < count; j++)
                {
                    ReadBaseline(ref rgbValue, ptr, j);
                }
            }

            sw.Stop();
            Console.WriteLine("Read* rgb baseline " + sw.ElapsedTicks);

            ReadBaseline(ref rgbValue, bytes, 0, p => *(RGB*)p);
            sw = Stopwatch.StartNew();
            for (var i = 0; i < iterations; i++)
            {
                for (int j = 0; j < count; j++)
                {
                    ReadBaseline(ref rgbValue, bytes, j, p => *(RGB*)p);
                }
            }

            sw.Stop();
            Console.WriteLine("Read rgb del baseline " + sw.ElapsedTicks);
        }