Using Info from User Space?
Using Info from User Space?
Posted Nov 3, 2013 16:58 UTC (Sun) by dlang (guest, #313)In reply to: Using Info from User Space? by raven667
Parent article: The power-aware scheduling mini-summit
it's not just the cores that need to be powered, it's the cache and other aspects of the chip.
it's not powering up two cores to get it done, or four cores to get it done in half the time.
it's powering up two cores and one set of cache, or powering up two cores and two sets of cache to get done 10% faster
from a strict power budget, powering one set of cache and taking 10% longer is probably a win, but is the user willing to sacrifice the performance?
and there are also secondary effects, the speed that you have the CPU set to run may impact the video performance, and if you have the user running something very demanding on the GPU, should you slow down the CPU (and therefor the GPU) to save power or not?
these are decisions that the kernel cannot make on it's own, because it doesn't know the user's priorities.