ping a Azure CDN endpoint to see how fast you can get the file and record the results.

gistfile1.cs

        static void Main(string[] args)
        {
            var url = "http://az590556.vo.msecnd.net/app/ec951196-2be1-4539-9e8f-3fc9f59590a9/client.js";

            while (true)
            {
                using (HttpClient client = new HttpClient())
                {
                    var sw = new Stopwatch();
                    sw.Start();
                    var result = client.GetAsync(url).Result;
                    sw.Stop();

                    IEnumerable<string> cache;
                    string cacheString = "NONE";

                    if (result.Headers.TryGetValues("X-Cache", out cache))
                    {
                        cacheString = string.Join("-", cache);
                    }

                    var message = string.Format("{0:G},{1},{2},{3}", System.DateTime.Now, result.StatusCode, sw.ElapsedMilliseconds, cacheString);
                    Console.WriteLine(message);
                    File.AppendAllText("result.txt", message + Environment.NewLine);
                }
                System.Threading.Thread.Sleep(1000);
            }
        }