On 2014-08-22, Henning Brauer <[email protected]> wrote: > * Federico Giannici <[email protected]> [2014-08-22 09:51]: >> On 08/22/14 08:22, Henning Brauer wrote: >> >* Adam Thompson <[email protected]> [2014-08-21 19:13]: >> >>Unless I've mis-understood all the emails and reports about this, it >> >>affects low-bandwidth queues, not low-bandwidth interfaces. >> >>In other words, limiting traffic to 50Mbps on a 1Gb link will work fine, >> >>limiting it to 50kbps on the same link will not. >> >> >> >>Yes/no? >> > >> >pretty much. >> >> I can imagine that it could be rather complicated to give the exact numbers, >> but can you give me an idea where the problem comes from, and maybe where I >> can find more info about it? > > kinda obvious: BW measurement and go/holdoff decision is (at most) once per > tick. ticks @ HZ, aka 100 ticks per second with HZ=100. If the NIC can > transfer "too much" data within one tick, the bw shaping becomes > inaccurate. Obviously worse the bigger the difference between > interface speed and desired queue speed is.
Any idea why this was so much less of a problem with altq?
