gistfile1.txt

It took 103 µs allocating an array with size 4000000
It took 37441 µs allocating an array with size 4000000
It took 43746 µs allocating an array with size 4000000
It took 42006 µs allocating an array with size 4000000
It took 41468 µs allocating an array with size 4000000
It took 42477 µs allocating an array with size 4000000
It took 43270 µs allocating an array with size 4000000
It took 41336 µs allocating an array with size 4000000
It took 42487 µs allocating an array with size 4000000
It took 41911 µs allocating an array with size 4000000

Program.cs

public static void Main(string[] args)
{
  for (var i = 0; i < 10; i++)
  {
    var stopwatch = Stopwatch.StartNew();
    
    var strings = new string[4000000];
    
    stopwatch.Stop();
    
    Debug.WriteLine("It took {0} µs allocating an array with size {1}", stopwatch.Elapsed.Ticks / (Stopwatch.Frequency / 1000000), strings.Length);
  }

  Console.WriteLine("Press Enter to exit...");
  Console.ReadLine();
}