Re: [Bloat] RED against bufferbloat

[Michael Welzl <michawe@ifi.uio.no>]

> On 25. feb. 2015, at 20.04, David Lang <david@lang.hm> wrote:
> 
> On Wed, 25 Feb 2015, Michael Welzl wrote:
> 
>> 2) Not everyone will always want FQ everywhere. There are potential disadvantanges (e.g. the often mentioned with-a-VPN-I'm-only-1-flow problem). What's necessary is to quantify them - to see how the effect of FQ (or FQ_CoDel's changed FQ) plays out, and you've done a great start there in my opinion.
> 
> If you only have one flow, then FQ should be just fine as you aren't competing against anything.
> 
> When your one flow starts mixing with other people's traffic, you will suffer a bit if they use multiple flows,

this is of course the situation I meant -


> but how could anything possibly tell that you are doing many things through that one flow rather than doing a single massive thing that should be limited for fairness with others?
> 
> The areas of the network that could have this knowledge don't have the competing flows, by the time you get to the point where you do have competing flows, you don't have any way of getting the knowledge (you can't trust whatever the user tells you as they could be just gaming you to get an unfair share of bandwidth)

Not enforcing anything will let things play out like before. FQ is the opposite end, by enforcing per-flow fairness. I'm not saying one is better than the other, but recently, quite often I hear that yes, FQ is always better  :-)

Not always clear and worth investigating is all I say.

Cheers,
Michael