Sep 23, 2016 03:26 PM|bruce (sqlwork.com)|LINK
most likely its not caching, but asp.net recycle. if not used for 20 minutes, asp.net shuts down, which also clears any asp.net server caches. after shutdown, the next request restarts the app pool. depending on the number and complexity of the dll's in
the bin folder, this can take a while (40 seconds is actually a pretty fast startup).
you change the recycle timeout, but there can be other causes. if you want your site to always be running, the most common method is a timer job that ping the site every couple minutes.