Hello Toke, Felix,
On Mon, 04 Apr 2022 20:21:24 +0200, Toke Høiland-Jørgensen <toke@xxxxxxx> wrote:
> +Felix
>
> Peter Seiderer <ps.report@xxxxxxx> writes:
>
> > Fill all requested rates (in case of ath9k 4 rate slots are
> > available, so fill all 4 instead of only 3), improves throughput in
> > noisy environment.
>
> How did you test this? Could you quantify the gains in throughput you saw?
Investigating some performance degradation of a wifi system original with ath5k
cards using a legacy kernel and madwifi driver compared against the
performance using a ath9k card running IBSS mode over long distance/with
additional amplifier and using iperf for measurement...
With the ath5k cards under bad conditions the throughput is going down below
10 Mbits/s but with stable throughput..., with the ath9k card and the exact same
setup there are short periods with good throughput values and periods up to 10-15
seconds with 0 Mbits/s...
The actual in-door/laboratory test setup is a wired connection between the
two wifi systems (with fixed attenuators in between) and an adjustable noise/
disturb signal induced by a signal generator...
Without this patch the 0 Mbits/s periods from the field test are reproducible,
with this patch applied we see a more or less stable throughput of 1-5 Mbits/s...
Regards,
Peter
>
> -Toke
>
> > Signed-off-by: Peter Seiderer <ps.report@xxxxxxx>
> > ---
> > net/mac80211/rc80211_minstrel_ht.c | 14 +++++++-------
> > 1 file changed, 7 insertions(+), 7 deletions(-)
> >
> > diff --git a/net/mac80211/rc80211_minstrel_ht.c b/net/mac80211/rc80211_minstrel_ht.c
> > index 9c6ace858107..cd6a0f153688 100644
> > --- a/net/mac80211/rc80211_minstrel_ht.c
> > +++ b/net/mac80211/rc80211_minstrel_ht.c
> > @@ -1436,17 +1436,17 @@ minstrel_ht_update_rates(struct minstrel_priv *mp, struct minstrel_ht_sta *mi)
> > /* Start with max_tp_rate[0] */
> > minstrel_ht_set_rate(mp, mi, rates, i++, mi->max_tp_rate[0]);
> >
> > - if (mp->hw->max_rates >= 3) {
> > - /* At least 3 tx rates supported, use max_tp_rate[1] next */
> > - minstrel_ht_set_rate(mp, mi, rates, i++, mi->max_tp_rate[1]);
> > - }
> > + /* Fill up remaining, keep one entry for max_probe_rate */
> > + for (; i < (mp->hw->max_rates - 1); i++)
> > + minstrel_ht_set_rate(mp, mi, rates, i, mi->max_tp_rate[i]);
> >
> > - if (mp->hw->max_rates >= 2) {
> > + if (i < mp->hw->max_rates)
> > minstrel_ht_set_rate(mp, mi, rates, i++, mi->max_prob_rate);
> > - }
> > +
> > + if (i < IEEE80211_TX_RATE_TABLE_SIZE)
> > + rates->rate[i].idx = -1;
> >
> > mi->sta->max_rc_amsdu_len = minstrel_ht_get_max_amsdu_len(mi);
> > - rates->rate[i].idx = -1;
> > rate_control_set_rates(mp->hw, mi->sta, rates);
> > }
> >
> > --
> > 2.35.1
