[Codel] usage of 'count' in codel

[Eric Dumazet]

On Sun, 2012-05-06 at 13:20 -0400, Jim Gettys wrote:



> I sort of think that having some upper queue time bound makes sense, if
> only to ensure that TCP's quadratic (un)responsiveness never gets out of
> hand.  But we agreed that having an implementation we could play with to
> observe reality would likely be better than hand-waving with no
> experience about how long the queue should be allowed to grow.

Even with normal tcp flows, codel is not responsive enough and too
conservative as is.

drop_next = control_law(drop_next)   with interval/sqrt(count)
increments ?

Something is _really_ wrong.

Thats few drops per second when we need far more than this.

interval = 100ms so you need count = 10000 to reach the rate of one drop
per ms, regardless of the link capacity.

control loop has no input on time of residence of packets.