Re: [PATCH] cpuidle: menu: use nr_running instead of cpuload forcalculating perf mult

[Arjan van de Ven]

On 6/4/2012 3:24 AM, Vladimir Davydov wrote:
> rq->cpuload strongly depends on cgroup hierarchy. For example, if hundreds of
> tasks are running inside cpu:/test cgroup, the sum of cpuload over all cpus
> won't exceed 1024 (by default). That makes the cpuidle menu governor take wrong
> decisions, which can negatively affect overall performance.

nr_running is the wrong answer... it is instantaneous, not longer term.
cpuidle wants a longer term, per cpu, notion of "busy", to use as proxy
for performance sensitivity.


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