If you compile your own MySQL server on FreeBSD and link with the LinuxThreads library, make sure to compile with the -DHAVE_BROKEN_REALPATH option.
The short version is that FreeBSD's realpath() isn't thread-safe. That causes badness with LinuxThreads on FreeBSD, because MySQL uses lots of relative paths and globally shared file descriptors may end up pointing to all the wrong places. I'll explain in more detail if I get a chance.
Oh, you could just read my post to the MySQL Internals mailing list, too, I guess. Heh. Sorry I can't link to the original. The web archives are a little funky. Hmm.
Posted by jzawodn at October 21, 2002 11:18 PM