[Bloat] AQM and PPP on Linux

[Alan Jenkins]

On 28/07/15 20:24, Juliusz Chroboczek wrote:
>> I would be very interested in flent benchmarks of your 3g device with
>> the 3 packet txqueue and with fq_codel, for the tcp_upload, rrul, and
>> rrul_be tests.
> Please send me detailed instructions, as well as information about how
> much traffic I'm going to have to pay for.
>
> FWIW, the RTT of the (unloaded) link varies tremendously.  Right now
> (around 21:20), I'm seeing 89ms to 823ms, with an average of 192ms and
> a standard deviation of 146ms.  It's better at night, mid-morning it's
> pretty much unusable.
>
> -- Juliusz

It's a straightforward usage.  My one concern would be ensuring you have 
netperf (netperf.org) built as required.

I suggest building netperf from source.  (Cite: flent requirements[1], 
and experience of failures with the Debian package)

     ./configure --enable-demo=yes --enable-histogram
make
     sudo make install

Untested (on my part) but documented[2] install is by debs at

https://software.opensuse.org/download.html?project=home:tohojo:flent&package=flent

or "pip install flent".

flent defaults to a 60 second test (and will run at whatever 4x tcp 
streams can manage).  Given the variation & high rtt I wouldn't want to 
shorten that very much.  One available graph from the output file will 
be what I assume Dave means when he says "mountain plot". That is, 
bandwidth & latency v.s. time.

Assuming EU (server taken from 
https://github.com/richb-hanover/CeroWrtScripts):

flent -H netperf-eu.bufferbloat.net rrul -t 
my-little-3G-connection-on-fq_codel

rrul is the test.  The -t value provides a caption.  Move the output 
file it mentions from /tmp (huh?) to somewhere more useful.  View 
available graphs with flent --gui <file>.


Alan


[1] 
http://netoptimizer.blogspot.co.uk/2014/09/mini-tutorial-for-netperf-wrapper-setup.html
[2] https://github.com/tohojo/flent/blob/master/README.rst

additional ref, including using your own server for netperf instead:

https://flent.org/intro.html#quick-start