Fire and forget to use ThreadPool.QueueUserWorkItem or async waiting?

Question

I have the following two methods that I use to make fire and forget accesses to http addresses. I originally used ThreadPool.QueueUserWorkItem, but was recommended to use Async Await because of problems with thread exhaustion, as this method could be called often.

First question: which one is better?

Second question - is the correct implementation of async running? Since I am debugging it, it seems synchronous, which is a big problem, since I need to free the calling asp.net thread and return the response to the user without waiting for the HTTP call to complete.

Call -

Send("http://example.com");

Method -

public static void Send(string url)
    {
        ThreadPool.QueueUserWorkItem(
            o =>
            {
                try
                {
                    HttpWebRequest request = (HttpWebRequest)WebRequest.Create(url);
                    request.KeepAlive = false;
                    request.Timeout = 5000;
                    var response = request.GetResponse();
                    response.Close();
                }
                catch (Exception ex)
                {
                    SendException(ex, url);
                }
            });
    }

ASYNC / AWAIT -

Call -

await SendAsync("http://example.com");

Method -

public async static Task SendAsync(string url)
    {
        try
        {
            HttpWebRequest request = (HttpWebRequest)WebRequest.Create(url);
            request.KeepAlive = false;
            request.Timeout = 5000;
            var response = await request.GetResponseAsync().ConfigureAwait(false);
            response.Close();
        }
        catch (Exception ex)
        {
            SendException(ex, url);
        }
    }

Answer 1

: ?

. ASP.NET, - HostingEnvironment.QueueBackgroundWorkItem; .

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