On 03/16/2018 12:25 PM, Vincent Guittot wrote: [...]
For a 15 seconds long test on a hikey 6220 (octo core cortex A53 platfrom), the cpufreq statistics outputs (stats are reset just before the test) : $ cat /sys/devices/system/cpu/cpufreq/policy0/stats/total_trans without patchset : 1230 with patchset : 14 If we replace the cfs thread of rt-app by a sysbench cpu test, we can see performance improvements: - Without patchset : Test execution summary: total time: 15.0009s total number of events: 4903 total time taken by event execution: 14.9972 per-request statistics: min: 1.23ms avg: 3.06ms max: 13.16ms approx. 95 percentile: 12.73ms Threads fairness: events (avg/stddev): 4903.0000/0.00 execution time (avg/stddev): 14.9972/0.00 - With patchset: Test execution summary: total time: 15.0014s total number of events: 7694 total time taken by event execution: 14.9979 per-request statistics: min: 1.23ms avg: 1.95ms max: 10.49ms approx. 95 percentile: 10.39ms Threads fairness: events (avg/stddev): 7694.0000/0.00 execution time (avg/stddev): 14.9979/0.00 The performance improvement is 56% for this use case.
How do you get this number? Normally we use the 'total time' value. [...]