ASP.net Session Public Service Information

• ASP.NET Session State: Architecture and Performance Considerations (blog post)
• ASP.NET Session State (MSDN)
• .NET Performance and Scalability Improvements (MSDN)
• Session State (MSDN)

What may or may not be useful to you.

In short, it works like this:

The InProc session state is the fastest, however it is also in-process, which means it is not shared (read "no benefit to web farms") and is lost if the process fails.

The State Service (aspnet_state.exe) is still pretty fast, but there is some overhead due to sorting between the worker process and the service itself. Maybe good because the IP addresses can be passed in the config, which means it can run on its own machine . It also gets out of the workflow process, meaning it can survive a process crash. Since it can run on the same machine, the state can be shared if all clients are using the same machine.

Sql server (or other custom provider). - The trend is (not always) the slowest of all, especially since there could potentially be a lot more disk I / O. However, it is also one of the most reliable solutions since the state can persist to disk, which means that it can not only survive a process crash on the web server, but it can also survive on the server. the state is being restored). Combined with clustering, this can provide a robust session system.