Messages in this thread | | | Subject | Re: [PATCH v5 09/14] sched: Add over-utilization/tipping point indicator | From | Dietmar Eggemann <> | Date | Mon, 6 Aug 2018 14:29:26 +0200 |
| |
On 08/06/2018 12:33 PM, Vincent Guittot wrote: > On Mon, 6 Aug 2018 at 12:08, Dietmar Eggemann <dietmar.eggemann@arm.com> wrote: >> >> On 08/06/2018 10:40 AM, Vincent Guittot wrote: >>> On Fri, 3 Aug 2018 at 17:55, Quentin Perret <quentin.perret@arm.com> wrote: >>>> >>>> On Friday 03 Aug 2018 at 15:49:24 (+0200), Vincent Guittot wrote: >>>>> On Fri, 3 Aug 2018 at 10:18, Quentin Perret <quentin.perret@arm.com> wrote: >>>>>> >>>>>> On Friday 03 Aug 2018 at 09:48:47 (+0200), Vincent Guittot wrote: >>>>>>> On Thu, 2 Aug 2018 at 18:59, Quentin Perret <quentin.perret@arm.com> wrote: >> >> [...] >> >>>> I think we're discussing two different things right now: >>>> 1. Should forkees go in find_energy_efficient_cpu() ? >>>> 2. Should forkees have 0 of initial util_avg when EAS is enabled ? >>> >>> It's the same topic: How EAS should consider a newly created task ? >>> >>> For now, we let the "performance" mode selects a CPU. This CPU will >>> most probably be worst CPU from a EAS pov because it's the idlest CPU >>> in the idlest group which is the opposite of what EAS tries to do >>> >>> The current behavior is : >>> For every new task, the cpu selection is done assuming it's a heavy >>> task with the max possible load_avg, and it looks for the idlest cpu. >>> This means that if the system is lightly loaded, scheduler will select >>> most probably a idle big core. >> >> AFAICS, task load doesn't seem to be used for find_idlest_cpu() ( >> find_idlest_group() and find_idlest_group_cpu()). So the forkee >> (SD_BALANCE_FORK) is placed independently of his task load. > > hmm ... so what is used if load or runnable load are not used ? > find_idlest_group() uses load and runnable load but skip spare > capacity in case of fork
Yes, runnable load and load are used, but from the cpus, not from the task.
[...]
| |