File upload progress

Question

I've been trying to track the progress of a file upload but keep on ending up at dead ends (uploading from a C# application not a webpage).

I tried using the WebClient as such:

class Program
{
    static volatile bool busy = true;

    static void Main(string[] args)
    {
        WebClient client = new WebClient();
        // Add some custom header information

        client.Credentials = new NetworkCredential("username", "password");
        client.UploadProgressChanged += client_UploadProgressChanged;
        client.UploadFileCompleted += client_UploadFileCompleted;

        client.UploadFileAsync(new Uri("http://uploaduri/"), "filename");

        while (busy)
        {
            Thread.Sleep(100);
        }
        Console.WriteLine("Done: press enter to exit");
        Console.ReadLine();
    }

    static void client_UploadFileCompleted(object sender, UploadFileCompletedEventArgs e)
    {
        busy = false;
    }

    static void client_UploadProgressChanged(object sender, UploadProgressChangedEventArgs e)
    {
        Console.WriteLine("Completed {0} of {1} bytes", e.BytesSent, e.TotalBytesToSend);
    }
}

The file does upload and progress is printed out but the progress is much faster than the actual upload and when uploading a large file the progress will reach the maximum within a few seconds but the actual upload takes a few minutes (it is not just waiting on a response, all the data have not yet arrived at the server).

So I tried using HttpWebRequest to stream the data instead (I know this is not the exact equivalent of a file upload as it does not produce multipart/form-data content but it does serve to illustrate my problem). I set AllowWriteStreamBuffering = false and set the ContentLength as suggested by this question/answer:

class Program
{
    static void Main(string[] args)
    {
        FileInfo fileInfo = new FileInfo(args[0]);
        HttpWebRequest client = (HttpWebRequest)WebRequest.Create(new Uri("http://uploadUri/"));
        // Add some custom header info
        client.Credentials = new NetworkCredential("username", "password");

        client.AllowWriteStreamBuffering = false;
        client.ContentLength = fileInfo.Length;
        client.Method = "POST";

        long fileSize = fileInfo.Length;
        using (FileStream stream = fileInfo.OpenRead())
        {
            using (Stream uploadStream = client.GetRequestStream())
            {
                long totalWritten = 0;
                byte[] buffer = new byte[3000];
                int bytesRead = 0;
                while ((bytesRead = stream.Read(buffer, 0, buffer.Length)) > 0)
                {
                    uploadStream.Write(buffer, 0, bytesRead);
                    uploadStream.Flush();
                    Console.WriteLine("{0} of {1} written", totalWritten += bytesRead, fileSize);
                }
            }
        }
        Console.WriteLine("Done: press enter to exit");
        Console.ReadLine();
    }
}

The request does not start until the entire file have been written to the stream and already shows full progress at the time it starts (I'm using fiddler to verify this). I also tried setting SendChunked to true (with and without setting the ContentLength as well). It seems like the data still gets cached before being sent over the network.

Is there something wrong with one of these approaches or is there perhaps another way I can track the progress of file uploads from a windows application?