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From: =?utf-8?Q?Toke_H=C3=B8iland-J=C3=B8rgensen?= <toke@toke.dk>
To: Paolo Valente <paolo.valente@unimore.it>
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	<2B5B39C9-A33D-46ED-84C6-56F237284B21@unimore.it>
Date: Mon, 27 Apr 2015 14:13:23 +0200
In-Reply-To: <2B5B39C9-A33D-46ED-84C6-56F237284B21@unimore.it> (Paolo
	Valente's message of "Mon, 27 Apr 2015 14:01:24 +0200")
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Cc: bloat <bloat@lists.bufferbloat.net>
Subject: Re: [Bloat] bufferbloat effects on throughput
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Paolo Valente <paolo.valente@unimore.it> writes:

> Thanks. So, if I understood correctly, average throughput may or may
> not be affected, but large throughput fluctuations will always occur
> in the presence of bufferbloat.

I'm always wary of saying 'always', but I'd hazard an 'often' ;)

> Sorry for my usual refrain, but =E2=80=A6 any pointers to tests, results,
> papers and the like?

Hmm, not sure if there's any papers dealing specifically with this.
However, it's quite easy to provoke this behaviour. Compare, for
instance,

 http://files.toke.dk/bufferbloat/rrul-pfifo_fast-all_scaled.pdf

with

 http://files.toke.dk/bufferbloat/rrul-fq_codel-all_scaled.pdf

The two top graphs on each are throughput (download and upload
respectively).

For the aggregate behaviour, I had some data on that in my presentation
at the IETF in Hawaii:

http://www.ietf.org/proceedings/91/slides/slides-91-iccrg-4.pdf

-Toke