Oliver Hohlfeld wrote: >> In ascii art, it might look like this: >> ======++++++++++++ >> - + >> - + >> - + >> - + > What exactly does this plot represent and on what measurement > data is it based on? What is your definition of "good" and "bad"? > Just response times? Where does it's shape comes from? > > Before (again) diving into debates on how bufferbloat marketing plots > should look like, I think we need to make sure that the marketing > is backed up by empirical data. > > --Oliver It's the inverse of a response time versus load graph for two cases, one with a very early degradation, the other with a normal one. It's a bowdlerized version of some real measurements of a REST-based system with and without a bug. I see the list software put in a link to the gif, so look at that: it's far better than my hack at "art".
Good and bad are indeed defined in terms of response time for a request-replay pair, with the appropriate units being part of my question. The normal shape of a response-time curve is a "hockey stick", like "_/". Technically it's a hyperbola with it's legs asymptotic to a pair of straight lines, one line horizontal at the value for load=1, and the second slanted at an angle that depends on the response time, the bottleneck time (if different), the think time between requests and the load. The right-side-up graph uses normal time units. I tried the experiment of inverting it and asking Dave and the list for an opinion on units: in my actual example they were normalized by dividing by the minimum response time, making it non-dimensional. --dave -- David Collier-Brown, | Always do right. This will gratify System Programmer and Author | some people and astonish the rest [email protected] | -- Mark Twain (416) 223-8968 _______________________________________________ Bloat mailing list [email protected] https://lists.bufferbloat.net/listinfo/bloat
