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To: Dave Taht <dave.taht@gmail.com>, Nils Andreas Svee <me@lochnair.net>
Cc: Cake <cake@lists.bufferbloat.net>, Make-Wifi-fast
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Date: Wed, 24 Feb 2021 11:51:42 +0100
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Subject: Re: [Cake] [Bloat] Fwd: [Galene] Dave on bufferbloat and jitter at
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Dave Taht <dave.taht@gmail.com> writes:

> wow, that is (predictably) miserable, even with cake. The only
> solution that is going to
> work is to somehow actively monitor your link quality and adjust cake
> to suit. Or we can start trying to use kathie's passive ping tools.

We have a PhD student working on a BPF-based implementation of pping:
https://github.com/xdp-project/bpf-examples/tree/master/pping

My hope is that this can end up being an always-on thing that runs on
the router and can be used to adjust the CAKE parameters as latency
spikes.

There are still a few rough edges on the implementation (most notably
the data output can become quite high), but it should otherwise be
usable, so feel free to take it for a spin. Needs a fairly recent LLVM
(10+ IIRC) to compile the BPF parts.

-Toke