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

[Toke Høiland-Jørgensen]

Pete Heist <pete at heistp.net> writes:

>> On Jul 30, 2018, at 1:28 PM, Toke Høiland-Jørgensen <toke at toke.dk> wrote:
>> 
>> Pete Heist <pete at heistp.net> writes:
>> 
>>> 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...
>
> Fair enough, we’ll see.
>
> The challenge now is eBPF classification doesn’t look like it will be
> usable on 3.16 (on FreeNet's routers). Maps weren’t introduced until
> 3.18 and tc support in 4.1. I’ll see what upgrades are possible.
>
> Also, if ISP Cake is a new qdisc, I don’t see now why it would need to
> support kernel versions where scalable classification by IP or MAC
> isn’t practical to do. The hard lower limit seems like 4.1, but also
> direct-action mode in 4.4 would be good for performance, and without
> the LPM trie in 4.11, classification by subnet would be more
> difficult...

Yeah, you'll probably need a newish kernel to do all the stuff you want
with eBPF...

-Toke