[Codel] [Bloat] The challenge

[Eric Dumazet]

On Tue, 2012-05-08 at 22:16 -0700, Simon Barber wrote:
> One question now remains - will codel AQM be sufficient on it's own in 
> getting delays down to levels that users are happy with for the common 
> latency sensitive interactive traffic - VoIP, gaming and Skype for 
> example - or are the further reductions that can be had with traffic 
> classification and smart queuing algorithms necessary? The nicest part 
> about codel on it's own is that it works on opaque packets - it will 
> handle VPNs and traffic within them nicely. It gets away from all the 
> complexity required to classify traffic in a world where traffic is 
> often trying to hide.

It all depends on the requirements you have.

To me, CoDel is a RED replacement, because it provides something easier
to deploy (no knobs). So it wont solve by itself cases where you want
something that could not be done by a single RED queue.

I like to see Codel as a basic unit, to replace RED (or pfifo if some
fools still use this for whatever reasons) in a tree involving
classifiers and FQ.