[Bloat] Measuring Latency

[Sebastian Moeller]

Hi Hal,


On Sep 13, 2014, at 21:41 , Hal Murray <hmurray at megapathdsl.net> wrote:

> 
>> When reading it, it strikes me, that you don't directly tell them what to
>> do; e.g. add a latency test during upload and download.  ...
> 
> Does round trip latency have enough info, or do you need to know how much is 
> contributed by each direction?

	RTT is fine, uni-directional transfer time would be too good to be true ;). The “trick” is to measure RTT without load and under hope-fully link saturating load and look at the difference in average RTT and the RTT distributions (so 3 numbers, 2% quantile, average, and 98% quantlie). I think it really is that simple...

> 
> If I gave you a large collection of latency data from a test run, how do you 
> reduce it to something simple that a marketer could compare with the results 
> from another test run?

	I believe the added latency under load would be a marketable number, but we had a discussion in the past where it was argued that marketing wants a number which increases with goodness, so larger = better, something the raw difference is not going to deliver….

Best Regards
	Sebastian

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