Re: [PATCH 6/6] cpufreq: schedutil: New governor based on scheduler utilization data

On 03/03/2016 12:20 PM, Rafael J. Wysocki wrote:

quoted

Here is a comparison, with frequency invariance, of ondemand and
interactive with schedfreq and schedutil. The first two columns (run and
period) are omitted so the table will fit.

        ondemand        interactive     schedfreq       schedutil
busy %  OR      OH      OR      OH      OR      OH      OR      OH
1.00%   0       68.96%  0       100.04% 0       78.49%  0       95.86%
1.00%   0       25.04%  0       22.59%  0       72.56%  0       71.61%
10.00%  0       21.75%  0       63.08%  0       52.40%  0       41.78%
10.00%  0       12.17%  0       14.41%  0       17.33%  0       47.96%
10.00%  0       2.57%   0       2.17%   0       0.29%   0       26.03%
18.18%  0       12.39%  0       9.39%   0       17.34%  0       31.61%
19.82%  0       3.74%   0       3.42%   0       12.26%  0       29.46%
40.00%  2       6.26%   1       12.23%  0       6.15%   0       12.93%
40.00%  0       0.47%   0       0.05%   0       2.68%   2       14.08%
40.00%  0       0.60%   0       0.50%   0       1.22%   0       11.58%
55.56%  2       4.25%   5       5.97%   0       2.51%   0       7.70%
55.56%  0       1.89%   0       0.04%   0       1.71%   6       8.06%
55.56%  0       0.50%   0       0.47%   0       1.82%   5       6.94%
75.00%  2       1.65%   1       0.46%   0       0.26%   56      3.59%
75.00%  0       1.68%   0       0.05%   0       0.49%   21      3.94%
75.00%  0       0.28%   0       0.23%   0       0.62%   4       4.41%

Aside from the 2nd and 3rd tests schedutil is showing decreased
performance across the board. The fifth test is particularly bad.

I guess you mean performance in terms of the overhead?

Correct. This overhead metric describes how fast the workload completes,
with 0% equaling the perf governor and 100% equaling the powersave
governor. So it's a reflection of general performance using the
governor. It's called "overhead" I imagine (the metric predates my
involvement) as it is something introduced/caused by the policy of the
governor.

thanks,
Steve