The most interesting thing is that Rezolus is written in Rust, we may embed it in our project TiKV and let TiKV can trace itself, no need to through outside tools like perf/bcc.
This statement is a bit sloppy. I think what the author is trying to say is the sampling rate must be such that it samples the shortest burst at least twice. Equivalently you could say that the sampling period should be no longer than half the length of the shortest burst.
This would accurately reflect the fundamental frequency of the burst, but if the burst is not sinusoidal you'll get aliasing. The effect of which will be to falsely indicate lower-frequency bursts that aren't actually present.
It's a bit scary that they consider it OK to spend 15% CPU on all of their servers for telemetry!