Power saving in Multi core.

[naveen yadav]

Dear All,

We are using ARM cortex a9. In below scenario, I want help.

Multi-Core Power Saving
Hot plug feature allows for making a processor offline and let the
system run as if there is only a single core.
Now,comes the scenario - Let there are '2' cores in the system both
running at a load of 40% (i.e. total load 80%), now in this case
ideally '1' CPU is sufficient.
So, if we make 2nd Core offline that will make the system execute
everything on core '1'.

But will there be any power saving if we make any core offline under
scenarios like this? Or will this have extra overhead?
What are the pros and cons of working like this on Multi-Core?

Regards
Naveen