Why does the Initial .NET Search Page Take Much Longer to Appear?

You might sometimes find that the loading of the initial Coveo .NET search interface page takes significantly longer than the following ones. The Coveo .NET search page is an ASP.NET application. An ASP.NET application takes a non-negligible time to load in the web server (IIS). Once loaded, subsequent requests to the application are returned much faster by IIS.

By default, ASP.NET Web pages are compiled dynamically when users first request a resource from a web site. After pages have been compiled the first time, the compiled resources are cached, so that subsequent requests to the same page are significantly more efficient. By default, IIS closes applications that have been inactive for some time. The next user requesting service from that closed application will experience a slow response while waiting for the initial loading to complete.

You can solve this problem by configuring CES to periodically send requests to a search application to ensure it is continuously loaded in IIS (see Pre-Loading a .NET Search Page to Prevent Display Delays).

Note: Refer to the Understanding ASP.NET Dynamic Compilation MSDN document for more information.