Re: Poor RT2880 performance

[Andreas Hartmann <andihartmann@01019freenet.de>]

Helmut Schaa schrieb:
> Hi,
> 
> On Mon, Feb 13, 2012 at 2:23 PM, Florian Fainelli <florian@openwrt.org> wrote:
>> I am playing with a RT2880-F based AP, with a N connected station, in a
>> residential environment.
> 
> Mind to provide the RF and RT chipset identifications? rt2x00 should print them
> out during module load (at least when compiled with debugging options).
> 
>> I could not get more than 26Mbits/sec TCP performance using iperf on both
>> sides,

Just for my understanding: did you test iperf payload in both directions
parallel or serial?

What about the hardware of the STA?

> Did aggregation kick in? What rate was selected by the AP?

I set the 80211.n options like this in hostapd.conf:

ieee80211n=1
ht_capab=[HT40+][SHORT-GI-40][SHORT-GI-20][TX-STBC1][MAX-AMSDU-3839][RX-STBC12][SMPS-STATIC][GF]

It's vitally to enable 40MHz channels, above [HT40+].

But you should put your own values into the config. You get them from iw
list of the AP interface.

> 
>> changing to a busier channel even made the performance drop down to
>> 5Mbits/sec, and remained like this.
> 
> Andreas also reported some issues as soon as the environment gets noisy,
> not sure what the root cause for this is :(

Yes, the issues I saw came up with nl80211 based STA interface running
parallel to a ralink legacy driver based interface (the payload from
ath9k interface was practically knocked out (DOS-attack :-)) - the
ralink legacy driver based STA sent on briskly).


Kind regards,
Andreas