[Bloat] Stab overhead caliculation and mpu for ingress shaping.

[Sebastian Moeller]

Hi Jesper,

> On Mar 2, 2017, at 08:55, Jesper Dangaard Brouer <brouer at redhat.com> wrote:
> 
> On Wed, 1 Mar 2017 22:36:25 +0100
> Sebastian Moeller <moeller0 at gmx.de> wrote:
> 
>> I typically would try to run
>> https://github.com/moeller0/ATM_overhead_detector to empirically
>> figure out the per packet overhead (but I note that this has never
>> been tested with PPPoA data as far as I can remember)
> 
> Cool project, you have an ATM_overhead_detector :-)

	Well, the name is a bit over optimistic, but the principle is sound and seems to work quite well. It is basically, just as README.md says, a pretty straight forward implementation of what you have developed & demonstrated in your Master’s thesis. While simply trying to illustrate the ATM cell staircase, it dawned upon me that since each packet uses an integer number of atm cells, it should be possible to estimate the “hidden" overhead, simply by looking at the how many unaccounted bytes are missing in the plot of the first ATM cell… 
Naming it detector is somewhat overplaying my cards, since I do not do a proper classification, but simply show whether the ATM staircase better fits the data than a simple linear fit… It is relatively useful though, on known ATM links to empirically figure out the actual per packet overhead.

> 
> Something I always missed, and I never got around to create such a
> tool.  Thanks for doing this :-) (I don't have time atm to play with
> it, but it looks cool)

	Thanks for the kind words. It was yours and Russel Stuarts work that got me started in the first place, so that is quite flattering ;)

Best Regards


> 
> -- 
> Best regards,
>  Jesper Dangaard Brouer
>  MSc.CS, Principal Kernel Engineer at Red Hat
>  LinkedIn: http://www.linkedin.com/in/brouer