On Wed, Jul 24, 2013 at 05:48:42PM +0100, Arjan van de Ven wrote:
I would expect performance to be disjoint for most tasks. If there was an overlap, the big would probably be less power efficient (as in energy/instruction) than the little so you would prefer to run on the little anyway.
In what way would you use the overlap?
if the scheduler thinks a task would be better off on the other side than where it is now, it could first move it into the "overlap area" on the same side by means of experiment, and if the task behaves as expected there, THEN move it over.
You could do that, but due to the different uarchs you wouldn't really know how a cpu bound task would behave on the other side. It would probably work for memory bound tasks.
Also, for interactive applications (smartphones and such) intermediate steps will increase latency when going little to big. Going the other way it would be fine.