Yes I think this is probably the only real metric of stress/strain that’s useful. (Original post with Dropout Ratio is here, and also discusses join queues).
Maybe it’s possible to measure fullness / spare space somehow as a factor of stress but it seems tricky.
Maybe it’s possible to measure mean / median / peak bandwidth and latency as a factor of stress, but this seems very difficult to utilise since these values will be different between nodes A and B vs A and C vs A and D etc, so how does the network agree on the bandwidth and latency of A in that situation and when do those figures transition A into a stressful state? Maybe using relative values rather than absolute values, but still, I’m not sure how to use this as an input to storecost just yet.
Some types of malice or incorrectness will be easy to detect so could be used as a measure of stress, but is more likely to feed into a penalty system and from that would indirectly affect dropping out, so the original Dropout Ratio is more useful as an input to storecost and malice can be isolated from storecost. I feel that malice / incorrectness is mainly useful as an input for penalties rather than stress measurement.
So after that bit of brainstorming (not complete, if you can think of other possible causes of stress I’d be keen to know), it seems like measuring stress is going to mainly be down to Dropout Ratio. That’s a nice bit of insight @digipl.
One other aspect to consider, is there any significant distinction to be made between individual node stress vs aggregated node stress vs overall network stress?
Maybe stress and strain and health are all synonyms in this case…? Is there a most useful word to use? Strain and stress seem to imply some spectrum of negativity, whereas health may also have some positive aspect to the spectrum. Subtle distinction for sure, but the word being used implies whether only ‘survival’ is important (care about managing stress/strain) or whether ‘excellence’ is also important (care about maximising health)…? Gets quite abstract and philosophical at this point but I think it matters.