[Long term] Performance: Caching the salt?

[LBiv]

This depends on whether incorrect login credentials terminate the session with the user. If they don't perhaps we should cache a username-salt pair and attach it to the session so that consecutive login attempts don't require repeated salt queries.

edit:

Although this maybe something that's already optimized by the database itself... It probably is.

[ladar]

The meta user object should be caching auth cred values.