Are there any objections from using ASP.NET Application_Start for warm-up?

Question

Does anybody known any objections from using ASP.NET method Application_Start for application warm-up?

Especially, for web-services, where is usually required to preload files, caches algorithms and etc.

Exist:

• Service Auto Start Providers, serviceAutoStartProvider, https://weblogs.asp.net/scottgu/auto-start-asp-net-applications-vs-2010-and-net-4-0-series , where we need:
  • Register new serviceAutoStartProvider, with concrete assembly name.
  • Assign serviceAutoStartProvider to IIS App.
  • Configure IIS App as AlwaysRunning.
• IIS 8.0 Application Initialization , https://learn.microsoft.com/en-us/iis/get-started/whats-new-in-iis-8/iis-80-application-initialization
  • Assign initializationPage to IIS App.
  • Configure IIS App as AlwaysRunning.

But, both methods require changes in IIS configuration for each application, what is uncomfortable in case with many-many applications and has additional risks on releases.

In accordance with ASP.NET Application Life Cycle Overview for IIS 5.0 and 6.0:

ASP.NET calls them (Application_Start and Application_End) once for the lifetime of the application domain, not for each HttpApplication instance.

Therefore, Application_Start seems like a great place for warm-up code, for example:

protected void Application_Start(object sender, EventArgs e)
{
    Task.Run(WarmUpBackend);
}

It requires only configure IIS App as AlwaysRunning. In WarmUpBackend we can preload everything what we need for web-services.

Answer 1

You might be better off using a Service autostart provider.

Scott Guthrie has a blog post about this.