Some people have seen the detail file listener go "crazy", and use lots of CPU. I've managed to reproduce the problem, and have committed a fix to the "stable" tree.
Please see http://git.freeradius.org/pre/ for tar files && debian files containing the fix. Or, see http://git.freeradius.org/ for instructions on grabbing the latest "stable" code from git. Alan DeKok. - List info/subscribe/unsubscribe? See http://www.freeradius.org/list/users.html