Hi Toke, On Apr 24, 2015, at 10:29 , Toke Høiland-Jørgensen <[email protected]> wrote:
> Sebastian Moeller <[email protected]> writes: > >> I know this is not perfect and the numbers will probably require >> severe "bike-shedding” > > Since you're literally asking for it... ;) > > > In this case we're talking about *added* latency. So the ambition should > be zero, or so close to it as to be indiscernible. Furthermore, we know > that proper application of a good queue management algorithm can keep it > pretty close to this. Certainly under 20-30 ms of added latency. So from > this, IMO the 'green' or 'excellent' score should be from zero to 30 ms. Oh, I can get behind that easily, I just thought basing the limits on externally relevant total latency thresholds would directly tell the user which applications might run well on his link. Sure this means that people on a satellite link most likely will miss out the acceptable voip threshold by their base-latency alone, but guess what telephony via satellite leaves something to be desired. That said if the alternative is no telephony I would take 1 second one-way delay any day ;). What I liked about fixed thresholds is that the test would give a good indication what kind of uses are going to work well on the link under load, given that during load both base and induced latency come into play. I agree that 300ms as first threshold is rather unambiguous though (and I am certain that remote X11 will require a massively lower RTT unless one likes to think of remote desktop as an oil tanker simulator ;) ) > > The other increments I have less opinions about, but 100 ms does seem to > be a nice round number, so do yellow from 30-100 ms, then start with the > reds somewhere above that, and range up into the deep red / purple / > black with skulls and fiery death as we go nearer and above one second? > > > I very much think that raising peoples expectations and being quite > ambitious about what to expect is an important part of this. Of course > the base latency is going to vary, but the added latency shouldn't. And > sine we have the technology to make sure it doesn't, calling out bad > results when we see them is reasonable! Okay so this would turn into: base latency to base latency + 30 ms: green base latency + 31 ms to base latency + 100 ms: yellow base latency + 101 ms to base latency + 200 ms: orange? base latency + 201 ms to base latency + 500 ms: red base latency + 501 ms to base latency + 1000 ms: fire base latency + 1001 ms to infinity: fire & brimstone correct? > > -Toke _______________________________________________ Bloat mailing list [email protected] https://lists.bufferbloat.net/listinfo/bloat
