Rails claims its CookieStore will "greatly increase the speed of the application" relative to other stores (the guide mentions a file store and a database store

Rails claims its CookieStore will "greatly increase the speed of the application" relative to other stores (the guide mentions a file store and a database store) [1]. The cookie is a base64 encoded hash serialization (i.e. completely reversible by the client), but "to prevent session hash tampering, a digest is calculated from the session with a server-side secret and inserted into the end of the cookie." I've not seen or performed myself any measurements of these claims. I have seen it suggested that CookieStore is the default because it is simpler in not requiring a database table, and not for any performance benefit. Without measuring, I can only guess the difference is dwarfed by the typical page load time. [1] http://guides.rubyonrails.org/security.html#session-storage http://guides.rubyonrails.org/security.html#session-storage