[Codel] The next slice of cake

[Jonathan Morton]

> On 21 Mar, 2015, at 18:09, Dave Taht <dave.taht at gmail.com> wrote:
> 
> I would like cake to have a byte limit instead.

That can probably be arranged.

> at (say) 2 or 4x the BDP

Hmm, we know the bandwidth, but what’s the delay?  It probably makes sense to use the Codel interval parameter for that purpose.  Four times that should make a reasonable headroom for most situations, and the drop-from-longest-queue behaviour should deal with excursions beyond that.

> It would be nice for cake (without shaping enabled) to be about to
> automatically sense the actual interface rate and size this outer
> limit appropriately, but I don't think mechanisms exist to do that.

It may be feasible to guess an initial value, and refine it based on the observed throughput when the queue is busy.

- Jonathan Morton