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

[Vladimir Davydov]

On 06/04/2012 02:32 PM, Peter Zijlstra wrote:
> On Mon, 2012-06-04 at 14:24 +0400, 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.
> >
> > To cope this, use nr_running last seen in __update_cpu_load() instead of
> > cpuload for calculating performance multiplier.
> What is cpuidle trying to do?

Basing on cpuload, it selects idle state. The less the load, the lowest 
the state.
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