The serverRuntime@appConcurrentRequestLimit setting is being exceeded

详细错误信息：

Error Summary:

HTTP Error 503.2 - Service Unavailable
The serverRuntime@appConcurrentRequestLimit setting is being exceeded. 

Detailed Error Information:

Module IIS Web Core 
Notification BeginRequest 
Handler StaticFile 

Error Code 0x00000000

解决方法请看：让Windows Server 2008+IIS 7+ASP.NET支持10万个同时请求