[Babel-users] how to set the pacing rate

[Juliusz Chroboczek]

>>> +    rc = setsockopt(s, SOL_SOCKET, SO_MAX_PACING_RATE, &rate, sizeof(rate));

>> It's only effective on TCP sockets, and only when using the FQ scheduler.

> I am under the impression that since linux 4.12 it works on udp, and I
> forget when it started working outside the fq scheduler...

Ah.

Still, I think that we should be able to do pacing in userspace.  At least
in the no-churn case, we should be able to predict how many updates per
unit of time we want to send, and spread them out across the update
interval.

I'd need to read up on data structures, as I don't currently understand
the tradeoffs between binary heaps and timer wheels.  (Same goes for
dealing with resends.  And Christof suggested that we should modify the
main event loop in babeld to use a proper data structure.)

-- Juliusz