Overcome compilation(?) pause on *secondary* initial ASP.Net application startup?

Question

After deploying an ASP.Net application to a new server, the first user to hit the app gets a long pause, presumably because the app is performing its initial compilation. However, this pause seems to also also occur after the application has timed out and unloaded itself from memory.

The first compilation would be tolerable as it only happpens once, but the 2nd one seems to me like it should be unnecessary....is there a workaround to address this issue? It would be nice to be able to extend the application timeout, but I only see a way to extend the session timeout, which I would rather not do, as this would keep all user sessions in memory for a long period of time.

Answer 1

A common way (though looks hackish to me) to keep the worker process alive is to have some program issue web requests to some URL in the application on a regular basis.

You can reduce the initial startup time by precompiling the ASP.NET app with aspnet_compiler.exe. This won't reduce the initial request time to zero (it'll still need to create the worker process and do other housekeeping.) but it'll noticeably reduce it.

Answer 2

That's IIS shutting down the worker process - the default is a 20 min idle time. In IIS6, you can configure the app pool and turn off the Idle timeout (on Performance tab). In IIS7, it's in the Advanced Settings.

Answer 3

I did find some recommended settings for the App Pools in IIS. The intended outcome of these settings is to reduce the number of times your application needs to go through the startup cycle. These settings should apply to IIS 6 as well as IIS 7:

• Recycle Worker Process: Disable. Use this only if you have multiple websites and are trying to isolate processes.
• Shutdown worker processes after being idle for (time in minutes): Disable unless you are sharing resources on your server. With this setting disabled, your website should not unload, ensuring that startup time for your site is as minimal as possible.