Re: iwlwifi aggregation info

Tomas Winkler
2008-08-01T12:40:05Z

On Fri, Aug 1, 2008 at 3:09 PM, Johannes Berg <johannes@sipsolutions.net> wrote:
> Had to think about this for a bit...
>
>> > Right. Which brings us back to the original point, why does the hw need
>> > to make the scheduling decision between agg and non-agg?
>>
>> There is no scheduling between aag and legacy queue in the sense of
>> qdisc .
>
> Right. So why are you saying we should have a separate qdisc for it?

I need a sw queue for it.

>> The aggregation need to be taken from single stream as
>> explained before,
>
> I think we simply agree on that. Which brings me back to my original
> point: to provide fairness within that stream we shouldn't have separate
> qdiscs for agg/non-agg parts of the stream.

You agree on the fact that it's a seperate stream but you still
doesn't want separate queue for it....

>> Iwlwifi has HW support for it that that's the whole story we just need
>> queueing support from the software buffering stopping and starting
>> queue and last but not least there is a classification just an
>> extension of the regular AC scheduling. The fairness between legacy
>> and agg queue must be provided by actually 'not scheduling'
>
> I don't understand what you mean by "not scheduling".

Not scheduling mean not string to prioritize streams in SW. I guess it means RR.

AIUI from the
> specs, there is no scheduling between aggregation/non-aggregation
> queues, or "within an AC" as I would say it.
>
> Therefore, I think we should remove the extra software queues and split
> up the single-AC stream into the different hardware queues in the
> driver, to be reunited in the FIFOs.

Aggregation is a separate stream even on the air it has it's own
rhythm. For example
from AP perspective you an have 3 streams for the same TID for 3
stations. Each station
has it's own rate of processing aggregation stream. It may vary on
number of packets and size of the aggregation
this is determine in association time.
So shell I stop the whole AC queue just because on station is slower?
Tomas