Messages in this thread | | | From | Vincent Guittot <> | Date | Mon, 4 Jun 2018 09:14:55 +0200 | Subject | Re: [PATCH v5 05/10] cpufreq/schedutil: get max utilization |
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On 4 June 2018 at 09:04, Juri Lelli <juri.lelli@redhat.com> wrote: > Hi Vincent, > > On 04/06/18 08:41, Vincent Guittot wrote: >> On 1 June 2018 at 19:45, Joel Fernandes <joelaf@google.com> wrote: >> > On Fri, Jun 01, 2018 at 03:53:07PM +0200, Vincent Guittot wrote: > > [...] > >> > IMO I feel its overkill to account dl_avg when we already have DL's running >> > bandwidth we can use. I understand it may be too instanenous, but perhaps we >> >> We keep using dl bandwidth which is quite correct for dl needs but >> doesn't reflect how it has disturbed other classes >> >> > can fix CFS's problems within CFS itself and not have to do this kind of >> > extra external accounting ? > > I would also keep accounting for waiting time due to higher prio classes > all inside CFS. My impression, when discussing it with you on IRC, was > that we should be able to do that by not decaying cfs.util_avg when CFS > is preempted (creating a new signal for it). Is not this enough?
We don't just want to not decay a signal but increase the signal to reflect the amount of preemption Then, we can't do that in a current signal. So you would like to add another metrics in cfs_rq ? The place doesn't really matter to be honest in cfs_rq or in dl_rq but you will not prevent to add call in dl class to start/stop the accounting of the preemption
> > I feel we should try to keep cross-class accounting/interaction at a > minimum.
accounting for cross class preemption can't be done without cross-class accounting
Regards, Vincent
> > Thanks, > > - Juri
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