Hi Viresh,
On 19/11/20 07:38, Viresh Kumar wrote: > As can be clearly seen, the load and requested_power numbers are simply > incorrect in the idle time based approach and the numbers collected from > CPU's utilization are much closer to the reality. > PELT time-scaling can make the util signals behave strangely from an external PoV. For instance, on a big.LITTLE system, the rq util of a LITTLE CPU may suddenly drop if it was stuck on a too-low OPP for some time and eventually reached the "right" OPP (i.e. got idle time). Also, as Peter pointed out in [1], task migrations can easily confuse an external observer that considers util to be "an image of the recent past". This will need testing on asymmetric CPU capacity systems, IMO. [1]: https://lore.kernel.org/r/20201120075527.gb2...@hirez.programming.kicks-ass.net
