[Cerowrt-devel] [Bloat] Two d-link products tested for bloat...

Isaac Konikoff konikofi at candelatech.com
Fri Feb 27 00:00:34 EST 2015

Something I'm not quite getting on the rtt_fair tests is that the upload 
and download labels do not look right for my test setup...how can I use 
netperf-wrapper better?

The lanforge box is sending and receiving all traffic with the AP under 
test in the middle, where eth1 to staX is download and staX to eth1 is 

So I setup the virtual sta's to associate with the AP, then run the 
following commands for the rtt_fair4be test:
netperf-wrapper -H sta1 -H sta2 -H sta3 -H sta4 --local-bind eth1 -x -t 
netgear6300 rtt_fair4be -f plot

However if I run a tcp_upload, tcp_download or tcp_bidirectional I can 
change the order of the arguments so that the upload/download labels 
match what each interface is reporting:

netperf-wrapper -H eth1 --local-bind sta1 -x -t netgear6300 tcp_download 
-f plot

Thanks for any help...


On 02/25/2015 08:37 PM, Dave Taht wrote:
> On Wed, Feb 25, 2015 at 8:22 PM, Isaac Konikoff
> <konikofi at candelatech.com> wrote:
>> On 02/25/2015 04:23 PM, Dave Taht wrote:
>>> On Wed, Feb 25, 2015 at 4:18 PM, Jonathan Morton <chromatix99 at gmail.com>
>>> wrote:
>>>>> Here's a comparison plot of box totals:
>>>> http://www.candelatech.com/downloads/rtt_fair4be-comparison-box-plot.png
>>>> That's a real mess. All of them utterly fail to get download bandwidth
>>>> anywhere near the upload (am I right in assuming it should ideally be
>>>> about
>>>> equal?), and the only ones with even halfway acceptable latency are the
>>>> ones
>>>> with least throughput in either direction.
>>> And I suspect that this was a test at the highest possible MCS rates
>>> and txpower. Isaac?
>> Yes, highest MCS for each AP and fw defaulted tx power. I can experiment
>> with attenuation and lower MCS rates as well.
> Be prepared to be horrified in disbelief at your results at the lower
> rates... and post them anyway.
> I note that rtt_fair4be is a pretty stressful, artificial benchmark,
> and to truly stress things out requires more
> than one tcp flow per station in each direction, or attempting to also
> exercise the 802.11e queues. Or interference. Or multicast.
> I do believe, that once these enormous latencies are clobbered via
> various techniques in make-wifi-fast that it is possible to get
> bandwidth per station over tcp to degrade nearly linearly, and achieve
> close to the theoretical rate of the air, and for latencies to remain
> (on this 4 station test) typically in the 4-14ms range at all but the
> lowest MCS rates.
> IMHO an AP that one day does well on these tests will also do much
> better on a variety of others. :)
> btw, I show a detailed graph of TCP's actual behavior under
> circumstances like these
> at nearly every talk, with data taken on the actual conference wifi.
> It never occurred to me once, to show the bar chart! (out of the 14+
> plots available).
> It might be helpful on your next test run to also do the simplest
> tests to a single station over each AP
> for a reference (tcp_upload, tcp_download, and tcp_bidirectional).
>>>> - Jonathan Morton

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