should we consider making CoDel the default to combat bufferbloat?

[Michal Schmidt]

On 10/28/2014 02:38 AM, Glen Turner wrote:
> I would have thought that it should be the system program which brings
> up the interface which should set the queuing behaviour. Neither the
> kernel nor systems know the intent of the use of the interface, and
> thus if CoDel, FIFO, or other AQM is appropriate.
> 
> Consider an ethernet interface, all using the same physical hardware:
> 
>  - enterprise LAN interface -- CoDel
> 
>  - ADSL link with PPP over ethernet -- ppp0 should run Codel, eth0
>  should run a short prioritised FIFO.
> 
>  - data centre LAN interface -- hierarchical queuing with a high
>  priority, random drop queue for control plane traffic (LACP, spanning
>  tree, etc) and CoDel for other traffic.
> 
> Intent is vital in setting the correct AQM for each interface. The
> program which configures interfaces (NetworkManager, systemd-networkd,
> ...) is where intent is best known.

Sure. NM, networkd, etc. may want to configure qdiscs per-interface.
Setting default_qdisc does not conflict with that.

Michal