300+ms of hotel wifi bufferbloat - peaking at 1.5 sec!

Mon Jun 1 18:58:26 UTC 2015

There's a bit of discussion on the AFMUG list about that speed test 
Dave. People with 500Mb, 1Gb,10Gb pipes were getting drastically 
different results depending on what "type" of test they did.

Josh Reynolds
CIO, SPITwSPOTS
www.spitwspots.com

On 06/01/2015 10:52 AM, Dave Taht wrote:
> I did the dslreports tests on the NANOG wifi while listening to srikanth today:
>
> http://www.dslreports.com/speedtest/593926
>
> And my own (flent data also in this dir)...
>
> http://snapon.lab.bufferbloat.net/~d/nanog/download_cdf.png
>
> pretty good bandwidth. Pretty horrific latency... a couple detours
> around the moon.
>
>
> On Sat, May 30, 2015 at 6:59 PM, Srikanth Sundaresan
> <srikanth at gatech.edu> wrote:
>> While I agree that upload speeds aren't great, it doesn't mean that the
>> buffers aren't big. Buffer sizes of the order of MB's are uncalled for at
>> the edge, unless we're talking really high speeds. The miniscule performance
>> increase for single TCP flows doesn't really justify the potential increase
>> in latency for everyone else.
>>
>>
>> On 5/30/15 6:25 PM, Steven Tardy wrote:
>>> There's a corollary of the bufferbloat phenomenon: buffer drain time. It's
>>> not the size of the buffer, but how long it takes to empty. And US ISPs
>>> continue to say "customers don't want upload speed".
>>> If the ISP upload speed was symmetric you'd likely never notice the 1-2MB
>>> of buffers.
>>>
>>> I guess what I'm getting at is why do you continue to say buffers are too
>>> big instead of saying ISP upload is too slow?
>>>
>>>
>>>> On May 30, 2015, at 1:50 PM, Dave Taht <dave.taht at gmail.com> wrote:
>>>>
>>>> http://www.dslreports.com/speedtest/578850
>>>>
>>>> I would get a kick out of it if folk here tried this new speedtest
>>>> periodically (on the "cable" setting) during the nanog conference. ;)
>>>> There is a hires option for more detail on the resulting charts...
>>>>
>>>> (or fiddled with "flent" (flent.org))
>>>>
>>>> --
>>>> Dave Täht
>>>> What will it take to vastly improve wifi for everyone?
>>>> https://plus.google.com/u/0/explore/makewififast
>
>