enables sites to use protocols other than HTTP and HTTPS. manages for both HTTP and non-HTTP requests
The IIS service that coordinates
the creation of IIS worker processes (w3wp.exe)
based on your application pool configuration
конфигурация храниться в ApplicationHost.config
Logs
written into: System Event Viewer
IIS Logs in C:\intepub\logs\LogFiles\W3SVC*
Application pool - This is a logical container, not a physical process
The application pool routes request processing for a set of applications in your website to a specific IIS worker process
IIS worker processes (w3wp.exe) - this is the actual runtime host for the application, where request processing takes place
Worker processes in one pool do not share resources with other pools
You can pass configuration settings to a single pool to, for instance, throttle the CPU utilization of its workers
Each application pool defaults to a single worker process, and you can configure your pools to include more
When we talk about restarting or recycling the application pool, we are actually talking about starting a new fresh worker process
Application
An IIS application maps a url in your website to a physical ASP.NET application domain that’s hosting your application code
When you are having performance issues, it’s the application code and its memory state that is usually causing the trouble. It could be a hang, high CPU, or a memory leak … the application is the piece we really need to restart.
Web server engine that can be customized by adding or removing modules
When processing is complete, HTTP.sys sends the response back to the browser.
HTTP.sys also has a cache and if it has the requested file in cache it can return it directly to the client browser without having to contact any IIS services for processing.