> On 10 Apr, 2020, at 4:16 pm, Kevin Darbyshire-Bryant 
> <[email protected]> wrote:
> 
> I have a 80/20mbit FTTC line into the house.  Egress shaping/control with 
> cake is simple, easy, beautiful and it works.  Tell it to use 19900Kbit, set 
> some min packet size, a bit of overhead and off you go.  Ingress has more 
> problems:
> 
> Assuming I do actually get 80Mbit incoming then the naive bandwidth setting 
> for CAKE would be 80Mbit.  Cake internally dequeues at that 80Mbit rate and 
> therefore the only way any flows can accumulate backlog is when they’re 
> competing with each other in terms of fairness(Tin/Host) and quantums become 
> involved…I think.

No.  If the dequeue rate is never less than the enqueue rate, then the backlog 
remains at zero pretty much all the time.  There are some short-term effects 
which can result in transient queuing of a small number of packets, but these 
will all drain out promptly.

For Cake to actually gain control of the bottleneck queue, it needs to *become* 
the bottleneck - which, when downstream of the nominal bottleneck, can only be 
achieved by shaping to a slower rate.  I would try 79Mbit for your case.

 - Jonathan Morton

_______________________________________________
Cake mailing list
[email protected]
https://lists.bufferbloat.net/listinfo/cake

Reply via email to