Hi,
chkconfig has a man page. You can read it with the command
According to the man page, you should be able to disable the daemon (if it is being managed with chkconfig) with the command:
As for what bigd actually is, I don't know. I suggest reading the /etc/init.d/bigd script to see what is actually being run, and then perhaps see if there is a man page for it.
Evo2.