On 7 February 2011 12:55, Vishwanath Sripathy <vishwanath.sripa...@linaro.org> wrote: > Vincent, > > On Mon, Feb 7, 2011 at 3:55 PM, Vincent Guittot > <vincent.guit...@linaro.org> wrote: >> Hi vishwa, >> >> I have passed cpufreq-bench on my platform. The results below have >> been reached with a sampling rate of 20ms and a sampling_down factor >> set to 10. >> >> I have a question about the sampling_down feature : The ondemand delay >> value is calculated before calling dbs_check_cpu, but dbs_check_cpu >> can modify rate_mult. This implies that if the rate_mult is set to 1 >> in dbs_check_cpu because we set something else than the max frequency, >> the next sampling period will be sampling_rate*sampling_down_factor >> (the one used for max freq) but the frequency can be the lowest one. >> We should rather calculate the delay after dbs_check_cpu or i miss >> something ? > Good point. Yes, with current implementation, change in rate_mult will > have effect only after next do_dbs_timer is called and the point > raised by you is perfectly valid. Why don't you post this query to > cpu_freq mailing list? >
ok, i'm going to send it > Vishwa > >> >> Vincent >> >> Test results with current implementation, 20ms sampling rate, >> sampling_down = 10: >> _round 1: 59.14% >> _round 2: 56.87% >> _round 3: 77.31% >> _round 4: 88.44% >> _round 5: 89.56% >> _round 6: 83.17% >> _round 7: 89.87% >> _round 8: 94.33% >> _round 9: 92.98% >> _round 10: 91.12% >> >> Test results when the delay is calculated after dbs_check_cpu, 20ms >> sampling rate, sampling_down = 10 : >> _round 1: 86.75% >> _round 2: 91.18% >> _round 3: 93.23% >> _round 4: 96.70% >> _round 5: 95.87% >> _round 6: 96.04% >> _round 7: 97.39% >> _round 8: 97.37% >> _round 9: 98.88% >> _round 10: 97.78% >> > _______________________________________________ linaro-dev mailing list linaro-dev@lists.linaro.org http://lists.linaro.org/mailman/listinfo/linaro-dev
