Messages in this thread | | | Subject | Re: [PATCH RFC RESEND v2 0/2] Prevent cpufreq update for only task on rq that sleeps | From | Steve Muckle <> | Date | Thu, 7 Sep 2017 11:10:58 -0700 |
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On 09/07/2017 09:14 AM, Joel Fernandes wrote: > I'm planning to rebase this series on Linus's master and post it > again, but just checking any thoughts about it? > > Just to add more context, the reason for not updating the frequency: > > - When a last dequeue of a sleeping task happens, it is sufficient to > update utilization without updating the frequency because if other > CPUs are busy then their updates will consider the utilization of the > idle CPU in the shared policy unless sufficient time has passed. > > - If the last dequeue of a sleeping task happens while all other CPUs > in the cluster are idle, then the cluster will likely enter > cluster-idle soon.
To clarify - when you say "last dequeue of a sleeping task happens" above, you're referring to the dequeue of the last task running on the CPU, correct? I.e. the CPU is about to go idle?
It's been a while since I've looked at this area so would like to hold off for a rebased version to review in further detail. But I think the concept is valid.
thanks, steve
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