Re: [BUG][2.6.30] Niced processes do not raise CPU frequency with ondemand

["Pallipadi, Venkatesh" <venkatesh.pallipadi@intel.com>]

On Fri, 2009-06-12 at 10:25 -0700, Frans Pop wrote:
> Thanks for the quick reply Venki.
> 
> On Friday 12 June 2009, Pallipadi, Venkatesh wrote:
> > What does ignore_nice under cpufreq/ondemand say?
> 
> Right, that's 1 (was not aware that existed :-P)
> And changing it to 0 solves the problem.

OK. Good to know that there are no kernel bugs with honoring
ignore_nice_load setting. :)
 
> Next question is: how and why does it get set?
> As userland has not changed (AFAIK), my first suspect remains the kernel.
> 

Kernel never sets this. It is initialized to 0 and provides a /sys
interface to user. I think it is set by some user app
(gnome-power-manager or some other app like that). That explains why it
is 0 initially after boot and gets changed later.

The support for ignore_nice_load=1 was broken in kernel for a short
while (arounf 2.6.28, IIRC). That may be the reason why this behavior
was not noticed earlier.

Thanks,
Venki