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Date: Thu, 7 May 2015 13:44:20 +0200 (CEST)
From: Mikael Abrahamsson <swmike@swm.pp.se>
To: jb <justin@dslr.net>
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Cc: bloat <bloat@lists.bufferbloat.net>
Subject: Re: [Bloat] DSLReports Speed Test has latency measurement built-in
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On Thu, 7 May 2015, jb wrote:

> There is a web socket based jitter tester now. It is very early stage but
> works ok.
>
> http://www.dslreports.com/speedtest?radar=1
>
> So the latency displayed is the mean latency from a rolling 60 sample 
> buffer, Minimum latency is also displayed. and the +/- PDV value is the 
> mean difference between sequential pings in that same rolling buffer. It 
> is quite similar to the std.dev actually (not shown).

So I think there are two schools here, either you take average and display 
+ / - from that, but I think I prefer to take the lowest of the last 100 
samples (or something), and then display PDV from that "floor" value, ie 
PDV can't ever be negative, it can only be positive.

Apart from that, the above multi-place RTT test is really really nice, 
thanks for doing this!

-- 
Mikael Abrahamsson    email: swmike@swm.pp.se