On 11/09/14 00:14, Helmut Schaa wrote:
please take a look at the attachments.... the first one shows the rc_stats and iperf stats side by side on the router(iperf is running in client mode in the router).....the second attachment is from a laptop which is running iperf in server mode.On Wed, Sep 10, 2014 at 10:42 AM, Arend van Spriel <arend@xxxxxxxxxxxx> wrote:On 09/10/14 03:26, Sourav wrote:We are using Ralink chip Rt3072L (using rt2800usb drivers rt2800usb.c),The Ralink USB hardware is quite bad in reporting TX status and as such minstrel_ht cannot do proper rate selection. If you watch the rc stats at /sys/kernel/debug/ieee80211/phy0/netdev\:wlan0-0/stations/xx:xx:xx:xx:xx:xx/rc_stats you might see a lot of rate selection "hopping". Regards. Helmut
I don't see a lot of rate "hopping" in the rc_stats file, (T,t and P) rates are pretty much stable.... yet there is a big difference between those rates and the throughput using iperf...... when you say "Ralink USB hardware is quite bad in reporting TX status", do you mean that the HW reports less tx rate to minstrel_ht and so its rate calculation is screwed up? Can you please let me know the section of code inside Rc_80211_minstrel_ht.c (or somewhere else) which deals with getting the tx rate from ralink HW?
-- Warm Regards, Sourav ______________________________________________________________________ This communication contains information which may be confidential or privileged. The information is intended solely for the use of the individual or entity named above. If you are not the intended recipient, be aware that any disclosure, copying, distribution or use of the contents of this information is prohibited. If you have received this communication in error, please notify me by telephone immediately. ______________________________________________________________________
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