[Make-wifi-fast] [PATCH RFC/RFT 4/4] mac80211: Apply Airtime-based Queue Limit (AQL) on packet dequeue

Toke Høiland-Jørgensen toke at redhat.com
Tue Oct 1 02:57:53 EDT 2019

Kan Yan <kyan at google.com> writes:

>> I guess the risk is lower when with a 24ms per-iface limit; but with
>> enough stations I guess it could still happen, no? So we should probably
>> handle this case...
> Each txq (per sta, per tid) is allowed to release at least the lower
> AQL limit amount of packet (default 4ms), which is not affected by
> other station's PS behavior and 4ms should be sufficient for most use
> cases.

Ah, I thought you'd meant each station can queue MIN(4ms, 24ms-<other
stations>). I see that is not the case; it's up to 10ms as long as the
total is less than 20ms, and up to 4ms otherwise. 

> The 24ms per-interface limit is an optimization to get good benchmark
> score in peak performance test, which usually only involve 1-2
> stations.

Gotta get those benchmark numbers in ;)

> The higher limit probably won't matter anymore when there are many
> stations. I haven't noticed side effects due to PS behavior in the
> ChromiumOS version. Still, it is better to be able to take frames in
> PS queue in to account,

As long as one station always gets its 4ms, I'm not too worried about
PS; but that was not the case in my patch :)

>> Cool. Are you going to submit a ported version of your implementation?
>> Then we can work from the two submissions and see if we can't converge
>> on something...
> Working on porting, should have something ready before the end of this
> week.



More information about the Make-wifi-fast mailing list