[Cake] Using cake to shape 1000’s of users.

[Toke Høiland-Jørgensen]

Pete Heist <pete at heistp.net> writes:

>> On Jul 30, 2018, at 12:55 PM, Toke Høiland-Jørgensen <toke at toke.dk> wrote:
>>> 
>>> I believe all you needto do is change the following in scg_cake.c:
>>> #define CAKE_QUEUES (1024)
>>> 
>>> Now I heard reports that above a certain number this breaks, but it
>>> might be enough for 32K or even 64k, or ~32 to 64 queues per customer,
>>> which might already help to spread out things a bit...
>> 
>> Has to fit in 16 bits, so 64k is the max; we really ought to have made
>> that parameter configurable...
>
> Couldn’t it still be made so now? Not sure of the performance impact
> though.

It could, but it would take some care. There's the issue of
power-of-two-ness and avoiding divides that Jonathan pointed out, and
the memory allocation would be complicated somewhat. Certainly doable,
but I'm not sure it's worth it for its own sake if the plan is to build
a new qdisc anyway...

-Toke