[Rpm] [ippm] Preliminary measurement comparison of "Working Latency" metrics

[MORTON JR., AL]

> -----Original Message-----
> From: rjmcmahon <rjmcmahon at rjmcmahon.com>
> Sent: Monday, October 31, 2022 2:53 PM
> To: Dave Taht <dave.taht at gmail.com>
> Cc: MORTON JR., AL <acmorton at att.com>; Rpm <rpm at lists.bufferbloat.net>;
> ippm at ietf.org
> Subject: Re: [Rpm] [ippm] Preliminary measurement comparison of "Working
> Latency" metrics
> 
> Would it be possible to get some iperf 2 bounceback test results too?
> 
> https://urldefense.com/v3/__https://sourceforge.net/projects/iperf2/__;!!BhdT!
> gmYpYN3pBO-aWMfjDRdVRFQ20aHQ5nDHOhEVY1y-
> MkFFyH8YmM4wf8cEtaxzvcwTMaCaJOCNRBtj0tnz9A$
> 
> Also, for the hunt algo, maybe use TCP first to get a starting point and
> then hunt? Just a thought.
> 
> Thanks,
> Bob
> >
<snip>

Thanks for your suggestion, Bob, and it's nice to meet you! 
I was only familiar with the "old" iperf2 at:
https://iperf.fr/iperf-doc.php
before your message and URL arrived (yet another segment of the elephant!).

I didn't quickly find whether your code will run on linux (ubuntu for me). I suppose I use the .tar.gz and compile locally. Let me know, I've got some other tools to check-out first.

You suggest the bounceback test option (I found it on the man page), but there are lots of options and six versions of bounceback!  Based on the results I already reported, can you suggest a specific version of bounceback and a set of options that would be a good first try?
(see the man page at https://iperf2.sourceforge.io/iperf-manpage.html )

Regarding our hunt algorithms (search for max), the new Type C algo (in release 7.5.0) locates the Max very quickly. I showed a comparison of our Type B and Type C search algorithms on a slide at the IPPM meeting in July. See Slide 10:
https://datatracker.ietf.org/meeting/114/materials/slides-114-ippm-sec-dir-review-discussion-test-protocol-for-one-way-ip-capacity-measurement-00

The measured capacity reaches 1 Gbps in about 1 second with the Type C algorithm, without choosing or testing for a starting point (our default starting point rate is ~500kbps, very low to accommodate "any" subscribed rate).

regards, and thanks again,
Al