gistfile1.cs

using System;
using System.Diagnostics;
using Microsoft.Xna.Framework;

// AoS 28-bytes
// this test uses an array of particle structures 28-bytes wide and processes each particle individually
namespace XNA360MathTest
{
    static class Program
    {
        struct ParticleStruct
        {
            public Vector3 pos;
            public Vector3 vel;
            public float timeremaining;
        }

        static unsafe void Main(string[] args)
        {
            const int NumParticles = 3200000;
            const float dt = 0.04f;
            const int NumSimulationRuns = 50;

            ParticleStruct[] particle_stream = new ParticleStruct[NumParticles];

            Random rnd = new Random();
            for (int i = 0; i < NumParticles; i++)
            {
                particle_stream[i].pos.X = (float)rnd.NextDouble();
                particle_stream[i].pos.Y = (float)rnd.NextDouble();
                particle_stream[i].pos.Z = (float)rnd.NextDouble();

                particle_stream[i].vel.X = (float)rnd.NextDouble();
                particle_stream[i].vel.Y = (float)rnd.NextDouble();
                particle_stream[i].vel.Z = (float)rnd.NextDouble();

                particle_stream[i].timeremaining = (float)rnd.NextDouble();
            }

            Stopwatch hptimer = new Stopwatch();

            float simAvg = 0.0f;
            float simMin = float.PositiveInfinity;
            float simMax = 0.0f;

            Vector3 dpdt;
            Vector3 dt_v = new Vector3(dt);

            for (int j = 0; j < NumSimulationRuns; j++)
            {
                hptimer.Reset();
                hptimer.Start();
                for (int i = 0; i < NumParticles; i++)
                {
                    Vector3.Multiply(ref particle_stream[i].vel, ref dt_v, out dpdt);
                    Vector3.Add(ref particle_stream[i].pos, ref dpdt, out particle_stream[i].pos);
                    particle_stream[i].timeremaining -= dt;
                }
                hptimer.Stop();
                float elapsedMS = hptimer.ElapsedTicks * 1000.0f / (float)Stopwatch.Frequency;
                simAvg += elapsedMS;
                simMin = (simMin > elapsedMS ? elapsedMS : simMin);
                simMax = (simMax < elapsedMS ? elapsedMS : simMax);
            }

            simAvg /= NumSimulationRuns;

            string outpt = "Average: " + simAvg + "   Min: " + simMin + "   Max: " + simMax;
            Console.WriteLine(outpt); // Set breakpoint here
        }
    }
}

gistfile2.cs

using System;
using System.Diagnostics;
using Microsoft.Xna.Framework;

// AoS 44-bytes
// this test uses an array of particle structures 44-bytes wide and processes each particle individually
namespace XNA360MathTest
{
    static class Program
    {
        struct ParticleStruct
        {
            public Vector3 pos;
            public Vector3 vel;
            public float timeremaining;

            // Represents stuff that the simulation doesn't care about, but needs to be in a pure AoS configuration
            public Vector4 JunkInTheTrunk0;
        }

        static unsafe void Main(string[] args)
        {
            const int NumParticles = 1600000;
            const float dt = 0.04f;
            const int NumSimulationRuns = 50;

            ParticleStruct[] particle_stream = new ParticleStruct[NumParticles];

            Random rnd = new Random();
            for (int i = 0; i < NumParticles; i++)
            {
                particle_stream[i].pos.X = (float)rnd.NextDouble();
                particle_stream[i].pos.Y = (float)rnd.NextDouble();
                particle_stream[i].pos.Z = (float)rnd.NextDouble();

                particle_stream[i].vel.X = (float)rnd.NextDouble();
                particle_stream[i].vel.Y = (float)rnd.NextDouble();
                particle_stream[i].vel.Z = (float)rnd.NextDouble();

                particle_stream[i].timeremaining = (float)rnd.NextDouble();
            }

            Stopwatch hptimer = new Stopwatch();

            float simAvg = 0.0f;
            float simMin = float.PositiveInfinity;
            float simMax = 0.0f;

            Vector3 dpdt;
            Vector3 dt_v = new Vector3(dt);

            for (int j = 0; j < NumSimulationRuns; j++)
            {
                hptimer.Reset();
                hptimer.Start();
                for (int i = 0; i < NumParticles; i++)
                {
                    Vector3.Multiply(ref particle_stream[i].vel, ref dt_v, out dpdt);
                    Vector3.Add(ref particle_stream[i].pos, ref dpdt, out particle_stream[i].pos);
                    particle_stream[i].timeremaining -= dt;
                }
                hptimer.Stop();
                float elapsedMS = hptimer.ElapsedTicks * 1000.0f / (float)Stopwatch.Frequency;
                simAvg += elapsedMS;
                simMin = (simMin > elapsedMS ? elapsedMS : simMin);
                simMax = (simMax < elapsedMS ? elapsedMS : simMax);
            }

            simAvg /= NumSimulationRuns;

            string outpt = "Average: " + simAvg + "   Min: " + simMin + "   Max: " + simMax;
            Console.WriteLine(outpt); // Set breakpoint here
        }
    }
}

gistfile3.cs

using System;
using System.Diagnostics;
using Microsoft.Xna.Framework;

// AoS 56-bytes
// this test uses an array of particle structures 56-bytes wide and processes each particle individually
namespace XNA360MathTest
{
    static class Program
    {
        struct ParticleStruct
        {
            public Vector3 pos;
            public Vector3 vel;
            public float timeremaining;

            // Represents stuff that the simulation doesn't care about, but needs to be in a pure AoS configuration
            public Vector4 JunkInTheTrunk0;
            public Vector3 JunkInTheTrunk1;
        }

        static unsafe void Main(string[] args)
        {
            const int NumParticles = 1600000;
            const float dt = 0.04f;
            const int NumSimulationRuns = 50;

            ParticleStruct[] particle_stream = new ParticleStruct[NumParticles];

            Random rnd = new Random();
            for (int i = 0; i < NumParticles; i++)
            {
                particle_stream[i].pos.X = (float)rnd.NextDouble();
                particle_stream[i].pos.Y = (float)rnd.NextDouble();
                particle_stream[i].pos.Z = (float)rnd.NextDouble();

                particle_stream[i].vel.X = (float)rnd.NextDouble();
                particle_stream[i].vel.Y = (float)rnd.NextDouble();
                particle_stream[i].vel.Z = (float)rnd.NextDouble();

                particle_stream[i].timeremaining = (float)rnd.NextDouble();
            }

            Stopwatch hptimer = new Stopwatch();

            float simAvg = 0.0f;
            float simMin = float.PositiveInfinity;
            float simMax = 0.0f;

            Vector3 dpdt;
            Vector3 dt_v = new Vector3(dt);

            for (int j = 0; j < NumSimulationRuns; j++)
            {
                hptimer.Reset();
                hptimer.Start();
                for (int i = 0; i < NumParticles; i++)
                {
                    Vector3.Multiply(ref particle_stream[i].vel, ref dt_v, out dpdt);
                    Vector3.Add(ref particle_stream[i].pos, ref dpdt, out particle_stream[i].pos);
                    particle_stream[i].timeremaining -= dt;
                }
                hptimer.Stop();
                float elapsedMS = hptimer.ElapsedTicks * 1000.0f / (float)Stopwatch.Frequency;
                simAvg += elapsedMS;
                simMin = (simMin > elapsedMS ? elapsedMS : simMin);
                simMax = (simMax < elapsedMS ? elapsedMS : simMax);
            }

            simAvg /= NumSimulationRuns;

            string outpt = "Average: " + simAvg + "   Min: " + simMin + "   Max: " + simMax;
            Console.WriteLine(outpt); // Set breakpoint here
        }
    }
}

gistfile4.cs

using System;
using System.Diagnostics;
using Microsoft.Xna.Framework;

// AoS 64-bytes
// this test uses an array of particle structures 64-bytes wide and processes each particle individually
namespace XNA360MathTest
{
    static class Program
    {
        struct ParticleStruct
        {
            public Vector3 pos;
            public Vector3 vel;
            public float timeremaining;

            // Represents stuff that the simulation doesn't care about, but needs to be in a pure AoS configuration
            public Vector4 JunkInTheTrunk0;
            public Vector3 JunkInTheTrunk1;
            public Vector2 JunkInTheTrunk2;
        }

        static unsafe void Main(string[] args)
        {
            const int NumParticles = 1600000;
            const float dt = 0.04f;
            const int NumSimulationRuns = 50;

            ParticleStruct[] particle_stream = new ParticleStruct[NumParticles];

            Random rnd = new Random();
            for (int i = 0; i < NumParticles; i++)
            {
                particle_stream[i].pos.X = (float)rnd.NextDouble();
                particle_stream[i].pos.Y = (float)rnd.NextDouble();
                particle_stream[i].pos.Z = (float)rnd.NextDouble();

                particle_stream[i].vel.X = (float)rnd.NextDouble();
                particle_stream[i].vel.Y = (float)rnd.NextDouble();
                particle_stream[i].vel.Z = (float)rnd.NextDouble();

                particle_stream[i].timeremaining = (float)rnd.NextDouble();
            }

            Stopwatch hptimer = new Stopwatch();

            float simAvg = 0.0f;
            float simMin = float.PositiveInfinity;
            float simMax = 0.0f;

            Vector3 dpdt;
            Vector3 dt_v = new Vector3(dt);

            for (int j = 0; j < NumSimulationRuns; j++)
            {
                hptimer.Reset();
                hptimer.Start();
                for (int i = 0; i < NumParticles; i++)
                {
                    Vector3.Multiply(ref particle_stream[i].vel, ref dt_v, out dpdt);
                    Vector3.Add(ref particle_stream[i].pos, ref dpdt, out particle_stream[i].pos);
                    particle_stream[i].timeremaining -= dt;
                }
                hptimer.Stop();
                float elapsedMS = hptimer.ElapsedTicks * 1000.0f / (float)Stopwatch.Frequency;
                simAvg += elapsedMS;
                simMin = (simMin > elapsedMS ? elapsedMS : simMin);
                simMax = (simMax < elapsedMS ? elapsedMS : simMax);
            }

            simAvg /= NumSimulationRuns;

            string outpt = "Average: " + simAvg + "   Min: " + simMin + "   Max: " + simMax;
            Console.WriteLine(outpt); // Set breakpoint here
        }
    }
}

gistfile5.cs

using System;
using System.Diagnostics;
using Microsoft.Xna.Framework;

// AoS 72-bytes
// this test uses an array of particle structures 72-bytes wide and processes each particle individually
namespace XNA360MathTest
{
    static class Program
    {
        struct ParticleStruct
        {
            public Vector3 pos;
            public Vector3 vel;
            public float timeremaining;

            // Represents stuff that the simulation doesn't care about, but needs to be in a pure AoS configuration
            public Vector4 JunkInTheTrunk0;
            public Vector3 JunkInTheTrunk1;
            public Vector2 JunkInTheTrunk2;
            public Vector2 JunkInTheTrunk3;
        }

        static unsafe void Main(string[] args)
        {
            const int NumParticles = 1600000;
            const float dt = 0.04f;
            const int NumSimulationRuns = 50;

            ParticleStruct[] particle_stream = new ParticleStruct[NumParticles];

            Random rnd = new Random();
            for (int i = 0; i < NumParticles; i++)
            {
                particle_stream[i].pos.X = (float)rnd.NextDouble();
                particle_stream[i].pos.Y = (float)rnd.NextDouble();
                particle_stream[i].pos.Z = (float)rnd.NextDouble();

                particle_stream[i].vel.X = (float)rnd.NextDouble();
                particle_stream[i].vel.Y = (float)rnd.NextDouble();
                particle_stream[i].vel.Z = (float)rnd.NextDouble();

                particle_stream[i].timeremaining = (float)rnd.NextDouble();
            }

            Stopwatch hptimer = new Stopwatch();

            float simAvg = 0.0f;
            float simMin = float.PositiveInfinity;
            float simMax = 0.0f;

            Vector3 dpdt;
            Vector3 dt_v = new Vector3(dt);

            for (int j = 0; j < NumSimulationRuns; j++)
            {
                hptimer.Reset();
                hptimer.Start();
                for (int i = 0; i < NumParticles; i++)
                {
                    Vector3.Multiply(ref particle_stream[i].vel, ref dt_v, out dpdt);
                    Vector3.Add(ref particle_stream[i].pos, ref dpdt, out particle_stream[i].pos);
                    particle_stream[i].timeremaining -= dt;
                }
                hptimer.Stop();
                float elapsedMS = hptimer.ElapsedTicks * 1000.0f / (float)Stopwatch.Frequency;
                simAvg += elapsedMS;
                simMin = (simMin > elapsedMS ? elapsedMS : simMin);
                simMax = (simMax < elapsedMS ? elapsedMS : simMax);
            }

            simAvg /= NumSimulationRuns;

            string outpt = "Average: " + simAvg + "   Min: " + simMin + "   Max: " + simMax;
            Console.WriteLine(outpt); // Set breakpoint here
        }
    }
}