Webclient slow at startup

Question

Here is the downloading time when I click update button:

First time = 5 sec
After first time = 2 sec

Why it takes more time at first time? Without wc.Proxy = null; it took 2 minute at first time, is there anything else that slow it down?

Stopwatch sw = new Stopwatch();
sw.Start();
using (WebClient wc = new WebClient())
{
    wc.Proxy = null;
    wc.Headers.Add("user-agent", "Mozilla/5.0 (Windows NT 6.1; WOW64; rv:17.0) Gecko/20100101 Firefox/17.0");
    wc.DownloadFile("http://example.com/folder/file.txt",@"folder/files/file.txt");
}
sw.Stop();

Could it be the web server takes some time to process the first request, but after it has some of your data cached and can respond more quickly? — Joel Coehoorn, Jan 03 '13 at 02:44
possible duplicate of [WebClient is very slow](http://stackoverflow.com/questions/6988981/webclient-is-very-slow) — Tofeeq Ahmad, Jan 03 '13 at 04:31

score 1 · Accepted Answer · edited May 23 '17 at 10:09

A possible solution to speed-up this process is caching. If the nature of the files/data that you are downloading is static, it is better to cache them on your web/app server.

Another solution would be firing the downloading process in a different UI thread, and possibility to use asynchronous process to free up your UI thread, to avoid freezing the application UI.

Here you are some references that might be helpful:

Webclient slow at startup

1 Answers1