Re: 5.2-rc2: low framerate in flightgear, cpu not running at full speed, thermal related?

[Rafael J. Wysocki]

On Wed, Jun 12, 2019 at 4:45 AM Doug Smythies <dsmythies@xxxxxxxxx> wrote:
>
> Hi,
>
> So, currently there seems to be 3 issues in this thread
> (and I am guessing a little, without definitive data):
>
> 1.) On your system Kernel 5.4-rc2 (or 4) defaults to the intel_pstate CPU frequency
> scaling driver and the powersave governor, but kernel 4.6 defaults to the
> acpi-cpufreq CPU frequency scaling driver and the ondemand governor.

Which means that intel_pstate works in the active mode by default and
so it uses its internal governor.

That governor is more performance-oriented than ondemand and it very
well may cause more power to be allocated for the processor - at the
expense of the GPU.

The lower-than-expected frame rate may result from that, in principle.

One way to mitigate that might be to use intel_pstate in the passive
mode (pass intel_pstate=passive to the kernel in the command line)
along with either ondemand or schedutil as the governor.