Re: [patch 0/7] sched: change nohz idle load balancing logic to pushmodel

[Nigel Cunningham]

Hi.

On 20/05/10 21:17, Dominik Brodowski wrote:
> Hey,
>
> On Thu, May 20, 2010 at 09:07:42PM +1000, Nigel Cunningham wrote:
> > "Load balancing tick" is still number one in my powertop list of top
> > causes of wakeups (sitting at ~60 to 80 per second as I type this, with
> > ~170 wakeups per second total). Comparing this to the numbers I posted
> > earlier, we seem to have a win.
> >
> > I do wonder, though, whether further work could still be done. If I take
> > one core offline, for example, I'm still getting load balancing ticks.
> > Intuitively, I'd expect there to be no need for them with only one core
> > available. But maybe I'm just ignorant of what's going on.
>
> Are you using HZ=1000, and is the CPU active ~ 6-8 % ? If so, is it just the
> regular timer tick while the CPU is active, and so not a real "wakeup"? (Or
> possibly double the number if both CPUs are active)

HZ is 1000, and the CPU running percentage in Powertop is low (2% when 
I'm not typing).

Regards,

Nigel
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