IIS7 Integrated vs Classic Pipeline - which uses more ASP.NET threads?

Question

With integrated pipeline, all requests are passed through ASP.NET, including images, CSS.

Whereas, in classic pipeline, only requests for ASPX pages are by default passe

Answer 1

If you look at machine.config, web.config and applicationHost.config in IIS 7, you can see that the way static content is served does not change when you switch between classic and integrated pipeline. The only thing that changes is whether requests mapped to asp.net pass through a managed module or the native ISAPI filter module.

The only thing that could affect performance is if you modify the default settings for authorization modules and any custom modules you've added to execute when handling requests for static content. And even here the overhead is probably negligible.

Therefore a more appropriate benchmark would be IIS 6 vs IIS 7, and I suspect IIS 7 would be the clear winner.