> + if (sample->read.time_running > 0) {
> + freq.tsc_freq = (1000 * sample->tsc) /
> sample->read.time_running;
> + freq.avg_freq = (1000 * sample->aperf) /
> sample->read.time_running;
> + if (sample->aperf > 0)
> + freq.bzy_freq = freq.tsc_freq * sample->mperf /
> sample->aperf;
Sorry didn't notice that earlier. The formula is not correct.
aperf/mperf is not necessarily the frequency, it is essentially a load average
of the CPU. It should be reported as such. Also only the ratio is
architecturally defined.
The right way to compute frequency is cycles / ref-cycles
TSC can be used to accurately compute CPU utilization tsc / ref-cycles
It would be useful to report all three metrics.
-Andi
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