Re: [Codel] sprout

[Dave Taht <dave.taht@gmail.com>]

On Wed, Jul 10, 2013 at 1:19 PM, Keith Winstein <keithw@mit.edu> wrote:
> Thank, Dave.
>
> We have a Web site with more info, a talk, and source code
> (http://alfalfa.mit.edu) if anybody is interested.

Good Talk! Nice way to spend lunch. Boy you talk fast.

The simple expedient of inverting the delay scale against the
bandwidth scale had never occurred to me on the graph, up and to the
right helps!

How did you dynamically stretch out the graphs like that in the preso?
I'd like very much to be able to zoom into those levels of detail and
out again.

Lastly,

what was sprout and sprout-ewma over codel? (rather than vs codel)

> Something that may interest folks here is that we compared
> Sprout-over-unlimited-buffer with TCP-Cubic-over-CoDel on these
> cellular-type links. That is, a scenario where the network operators
> implemented CoDel inside the LTE/UMTS/1xEV-DO base station (for the
> downlink) and the phone manufacturers implemented CoDel inside the
> "baseband" chip for the uplink.

of course I'm always after people to attempt fq_codel in cases like this...

or fq + X, whatever X is....

>
> Bottom line results is that for the case where a cellular user can control
> all their own flows, it's roughly a wash. To a first approximation, you can
> fix bufferbloat on a cellular network *either* by putting CoDel inside the
> base station and baseband chip (and otherwise running the same endpoint
> TCP), *or* by changing the endpoints but leaving the base station and
> baseband chip unmodified.
>
> Obviously we benefit dramatically from the per-user queues of the cellular
> network. By contrast, in a typical house with a bufferbloated cable modem
> where one user can cause big delays for everybody else, you can't fix
> bufferbloat by fixing just one endpoint. We will have some results soon on
> whether you can fix it by fixing all the endpoints (but still leaving the
> "bloated" gateway intact).


>
> Cheers,
> Keith
>
> On Wed, Jul 10, 2013 at 3:30 PM, Dave Taht <dave.taht@gmail.com> wrote:
>>
>> I haven't been paying a lot of attention to rmcat and webrtc until
>> recently, although I'd had a nice discussion with keith on it a while
>> back..
>>
>> this particular thread sums up some interesting issues on that front.
>>
>> http://www.ietf.org/mail-archive/web/rmcat/current/msg00390.html
>>
>> --
>> Dave Täht
>>
>> Fixing bufferbloat with cerowrt:
>> http://www.teklibre.com/cerowrt/subscribe.html
>
>



-- 
Dave Täht

Fixing bufferbloat with cerowrt: http://www.teklibre.com/cerowrt/subscribe.html