Re: [ 028/108] sched/nohz: Rewrite and fix load-avg computation -- again

Ben Hutchings
2012-07-24T14:07:20Z

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On Mon, 2012-07-23 at 02:07 +0100, Ben Hutchings wrote:
> 3.2-stable review patch. If anyone has any objections, please let me know.
>
> ------------------
>
> From: Peter Zijlstra <a.p.zijlstra@chello.nl>
>
> commit 5167e8d5417bf5c322a703d2927daec727ea40dd upstream.
>
> Thanks to Charles Wang for spotting the defects in the current code:
>
> - If we go idle during the sample window -- after sampling, we get a
> negative bias because we can negate our own sample.
>
> - If we wake up during the sample window we get a positive bias
> because we push the sample to a known active period.
>
> So rewrite the entire nohz load-avg muck once again, now adding
> copious documentation to the code.
[...]

Based on <http://bugs.debian.org/674153>, I think we also need:

556061b sched/nohz: Fix rq->cpu_load[] calculations
5aaa0b7 sched/nohz: Fix rq->cpu_load calculations some more

Does this ('sched/nohz: Rewrite and fix load-avg computation -- again')
depend in any way on those, or are they separate fixes?

Ben.

--
Ben Hutchings
If more than one person is responsible for a bug, no one is at fault.

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