[Silentfood]

killall bases all terminates on the currently ran processes the current user can access. It's not based on file usage.

Quote:

killall sends a signal to all processes running any of the specified commands. If no signal name is specified, SIGTERM is sent. Signals can be specified either by name (e.g. -HUP) or by number (e.g. -1). If the command name contains a slash (/), processes executing that particular file will be selected for killing, independent of their name. killall returns a zero return code if at least one process has been killed for each ilisted command. killall returns zero otherwise. A killall process never kills itself (but may kill other killall processes).

Sources: killall documentation