POSIX threads policy and priority

Hi!

I am using posix threads in my application. I am explicitly setting the priorities and the scheduling policy. POSIX threads support 3 types of scheduling - FIFO, RR and OTHER. My second thread needs most of the CPU cycles. Can anybody please clarify what the scenario will be if I use FIFO or RR for my threads but assign different priorities to them? How can I give my second thread the greater part of the CPU cycles?

Thanks and regards,

Arun

Doesn't this fall under thread niceness, not scheduling protocol? I do not know what syscall controls it, but it should be decently trivial to look up.