[Intel-gfx] [PATCH 1/2] drm/i915: Boost RPS frequency for CPU stalls

[Chris Wilson]

On Thu, Aug 29, 2013 at 03:04:13AM +0000, Meng, Mengmeng wrote:
>    Hi,
> 
>    It's Power results on IVB mobile. With the patches, workloads would cost
>    more power.
> 
>                                     mobile IVB
>                    git-53749d3         git-53749d3 with four     Patches VS no
>    workloads                                  patches                Patch
>              Average Watt-hour  Time  Average Watt-hour  Time  Average Watt-hour
>               watt                     watt                     watt
>      idle     25.6      3.7      9′    25.7      3.8      9′   100.39%  102.70%
>      video    30.7      2.7    5'30"   30.9      2.7    5'30"  100.65%  100.00%
>      game     33.5      6.4    11'43"  33.9      6.5    11'41" 101.19%  101.56%

That too is inline with expectations. Boosting the frequency everytime
we need a result from the GPU from idle is going to burn through power
more quickly. I think this a reasonable result though - I think the
extra power use is justified by the snappier response.

It must be time for someone to step forward and review the patches, or to
check the results on their favourite workload.
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre