WCF service in Azure worker role slow on first request after being idle

Question

We have an Azure worker role that exposes a RESTful WCF service (using System.ServiceModel.Web) through a ServiceHost. The performance is irreproachable on massive traffic,

Answer 1

The default AppPool timeout is 20 minutes. Might you be running into this? If so, you can add something like this to a startup script to change the timeout:

%windir%\system32\inetsrv\appcmd set config -section:applicationPools -applicationPoolDefaults.processModel.idleTimeout:00:00:00

Here's another answer I posted, to a different question, discussing this further.