rlm_detail perfomances

Hi all, I have question for those who use rlm_detail module. I saw in source code that this module is thread unsafe. My understanding is that will not avoid FreeRADIUS to run multi-thread, but that only one thread will be able to log details at a time. Am I right? Second question: does anybody use rlm_detail on a production platform? If yes, what is the request rate that can be supported nicely? Many thanks for any testimonial. Geof.