By
default, Asp.Net MVC support session state. Session is used to store
data values across requests. Whether you store some data values with in
the session or not Asp.Net MVC must manage the session state for all the
controllers in your application that is time consuming. Since, session
is stored on server side and consumes server memory, hence it also
affect your application performance.
Session Less Controller
If some of the controllers of your Asp.Net MVC application are not using session state features, you can disable session for those controller and can gain slight performance improvement of your application. You can simplify session state for your application by using available options for session state.In Asp.Net MVC4, SessionState attribute provides you more control over the behavior of session-state by specifying the value of SessionStateBehavior enumeration as shown below:
SessionStateBehavior Enumeration's Value
Value
Description
Default
The default Asp.Net behavior is used to determine the session state behavior.
Disabled
Session state is disabled entirely.
ReadOnly
Read-only session state behavior is enabled.
Required
Full read-write session state behavior is enabled.
In Asp.Net MVC, TempData use session state for storing the data values across requests. Hence, when you will disabled the session state for the controller, it will throw the exception as shown below:
