I'm using OS X 10.8.4 on a Mac Mini with 2.3 GHz Core i5 and 8 GB RAM. For security reason I have to lock my computer to screensaver while I leave my seat for a while. I set it up so that password login is required to dismiss screensaver.
However, while I'm login and after login the system is very slow. (at least 30 sec to type the first character for my password). After login for a while it became normal.
I suppose the reason might be that the system is loading everything from hard disk? If so how can I fix that?