4 ms·

I'm confused, aren't "don't fall below your spec" and "hit your metric" synonyms? In what field are they not?

• nl 6y ago
  "Hit your metric" commonly refers to average (or some percentage of average) performance being within bounds. It's pretty rare in software for it to define minimum performance. There's good reasons for this - software is interacting with intrinsicly messy things (like humans) and so performance outliers are a big factor. It's pretty common in software for the worse case to be 10x the "hit your metric" case, and this isn't viewed as bad: the worst case happens rarely enough for the trade off to be worth it.
  • neltnerb 6y ago
    Ah, thanks for the clarification. I am coming from the hardware world, through raw assembly, to C so my path is very much the assumption that if the microcontroller is going to control a feedback loop that stabilizes at 10MHz it will be guaranteed to do so. But I suppose that I actually do that by overspecifying things nowadays since it's much too unpredictable as you say to predict how long things will take. To me if you say you sample at 100kHz you sample at a minimum of 100kHz. Very very good to know that if I work with a firmware engineer that they won't hear the same thing as I mean if I say that it needs to hit a 100kHz sampling rate. It would be very disappointing if they wrote a loop designed to average a 100kHz sampling rate with random jitter... (kidding mostly, I'd assume they would at least not do that).
    • SonOfLilit 6y ago
      Firmware engineers would probably think in the same terms as you about sampling frequency.