Difference between idleTimeout and ShutdownTimeout

I am trying to relax my website's session expiration policy so that the users may specify the session timeout interval.

I need to figure out what website related settings should I specify in order not to limit the users too much. For example, one might want a 1 day interval. I will be using tickets to accomplish that.

Now, I know I can specify the idleTimeout and shutdownTimeout in my website's web.config file (I prefer this method as it's damn easy to adjust it without the whole deployment hassle after).

According to MS specs found here: http://msdn.microsoft.com/开发者_StackOverflow中文版en-us/library/system.web.configuration.hostingenvironmentsection.aspx it seems I have to set both idleTimeout and shutdownTimeout values.

idleTimeout = Gets or sets the amount of time, in minutes, before unloading an inactive application.

shutdownTimeout = Gets or sets the amount of time, in seconds, to gracefully shut down the application.

But I could not figure out what's the difference between them. Should I set them all to "Infinite" to give users complete control? Is it enough only to set idleTimeout? Or only shutdownTimeout?

And most of all, will this really work for my desired scenario?

Thanks.

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I believe ShutdownTimeout refers to the amount of time to allow the process to attempt to shutdown gracefully - once that expires it will be killed forcefully.

IdleTimeout is the amount of idle time to allow before attempting to shut it down.