iisreset -- 对象是整个IIS服务器，这个操作会先停止万维网的服务（World Wide Web Publishing Service）然后在重启此服务，因此所有的网站都会先停止服务然后在重新开始服务。
As pointed out, iisreset will stop and start the World Wide Web Publishing Service. This, of course, applies to all of your application pools. I'm sure you noticed a process being created for each application pool. This process will handle requests for all websites associated with it.