Re: [PATCH] Track accurate idle time with tick_sched.idle_sleeptime

[Ingo Molnar]

* Venki Pallipadi <venkatesh.pallipadi@xxxxxxxxx> wrote:

> Current idle time in kstat is based on jiffies and is coarse grained. 
> tick_sched.idle_sleeptime is making some attempt to keep track of idle 
> time in a fine grained manner. But, it is not handling the time spent 
> in interrupts fully.
> 
> Make tick_sched.idle_sleeptime accurate with respect to time spent on 
> handling interrupts and also add tick_sched.idle_lastupdate, which 
> keeps track of last time when idle_sleeptime was updated.
> 
> This statistics will be crucial for cpufreq-ondemand governor, which 
> can shed some conservative gaurd band that is uses today while setting 
> the frequency. The ondemand changes that uses the exact idle time is 
> coming soon.

nice stuff! I've added your patch to the scheduler queue - but this will 
probably be 2.6.24 material.

Acked-by: Ingo Molnar <mingo@xxxxxxx>

	Ingo
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