[Bloat] Fwd: Did *bufferbloat* cause the 2010 flashcrash?

[Toke Høiland-Jørgensen]

"Steinar H. Gunderson" <sgunderson at bigfoot.com> writes:

> On Fri, Aug 07, 2015 at 04:43:19PM +0200, Sebastian Moeller wrote:
>>> switching to IP-level fairness makes life hard for the torrent
>>> user (not that it seems to even exist in fq_codel;
>> 	fq_codel does not care as far as I know one can specify different
>> 	hashing schemes (expect I have not tried it myself so that might not
>> 	work).
>
> How? I've searched for it, I've checked the documentation, I've looked for it
> in the code. What am I missing?

The mechanism is not specific to fq_codel, it's a tc thing. You can
attach arbitrary tc filters which fq_codel will then use as a
classifier. http://lartc.org/howto/lartc.adv-filter.hashing.html has
some (fairly old) information on this, but I've never tried it in
practice with fq_codel so can't give you any more specific pointers.

An alternative, of course, is to try out cake. Jonathan did a
presentation on it at Battlemesh yesterday, which also has instructions
on how to obtain it:
http://battlemesh.org/BattleMeshV8/Agenda?action=AttachFile&do=view&target=cake-battlemesh-v8.pdf

-Toke