load balancing scheduler on linux

[Murali N]

Hi,
Can somebody give pointers to the load balancing scheduler on Linux. I
hope this is the default scheduler which is used on most of the linux
systems on SMP environment.
I would like to know how the scheduler takes a decision to migrate
some of the processes to the another core?

I have a scenario like below:

If CORE0 is running per say 2 threads which can be handled by CORE0
itself ( by running at higher frequencies ) without enabling the CORE1
( put into some low power mode ).
How the scheduler takes this kind of decision intelligently!!!

-- 
Regards,
Murali N