Comparing struct/class access with shuffled arrays

StructsVsClassesTestUnity.cs

using System;
 
using UnityEngine;
 
class TestScript : MonoBehaviour
{
    struct ProjectileStruct
    {
        public Vector3 Position;
        public Vector3 Velocity;
    }
 
    class ProjectileClass
    {
        public Vector3 Position;
        public Vector3 Velocity;
    }
 
    void Start()
    {
        const int count = 10000000;
        ProjectileStruct[] projectileStructs = new ProjectileStruct[count];
        ProjectileClass[] projectileClasses = new ProjectileClass[count];
        for (int i = 0; i < count; ++i)
        {
            projectileClasses[i] = new ProjectileClass();
        }
        Shuffle(projectileStructs);
        Shuffle(projectileClasses);
        
        // create an array of shuffled indices
        int[] indices = new int[count];
        for (int i = 0; i < count; i++)
        {
            indices[i] = i;
        }
        Shuffle(indices);
         
        System.Diagnostics.Stopwatch sw = System.Diagnostics.Stopwatch.StartNew();
        for (int i = 0; i < count; ++i)
        {
            UpdateProjectile(ref projectileStructs[indices[i]], 0.5f);
        }
        long structTime = sw.ElapsedMilliseconds;
 
        sw.Reset();
        sw.Start();
        for (int i = 0; i < count; ++i)
        {
            UpdateProjectile(projectileClasses[indices[i]], 0.5f);
        }
        long classTime = sw.ElapsedMilliseconds;
 
        string report = string.Format(
            "Type,Time\n" +
            "Struct,{0}\n" +
            "Class,{1}\n",
            structTime,
            classTime
        );
        Debug.Log(report);
    }
 
    void UpdateProjectile(ref ProjectileStruct projectile, float time)
    {
        projectile.Position += projectile.Velocity * time;
    }
 
    void UpdateProjectile(ProjectileClass projectile, float time)
    {
        projectile.Position += projectile.Velocity * time;
    }
 
    public static void Shuffle<T>(T[] list)  
    {
        System.Random random = new System.Random();
        for (int n = list.Length; n > 1; )
        {
            n--;
            int k = random.Next(n + 1);
            T value = list[k];
            list[k] = list[n];
            list[n] = value;
        }
    }
}