[ath9k-devel] Debugging very slow ath9k AP performance

[Ben Greear <greearb@candelatech.com>]

On 04/05/2012 04:12 PM, Ben Greear wrote:
> I am seeing very slow performance when I have around 100
> stations connected to an AP (ath9k on both ends).
>
> It seems like the station side is doing fine, but on the
> AP side, it appears there are always lots of pending frames
> and it is only transmitting about 100 pkts per second if my stats
> are correct.
>
> Kernel is 3.3.1+ with the troublesome ath9k patch reverted.
>
> I would be greatful for any pointers as to what might be
> causing this slowdown.

Hrm, just noticed dmesg is full of these messages:

ieee80211 wiphy0: dropped TX filtered frame, queue_len=0 PS=0 @7658178
ieee80211 wiphy0: dropped TX filtered frame, queue_len=0 PS=0 @7658178
net_ratelimit: 33 callbacks suppressed
ieee80211 wiphy0: dropped TX filtered frame, queue_len=0 PS=0 @7671545

Will have to go figure out what that means...

Ben

>
>
> [root at lanner-atom ~]# cat /debug/ieee80211/wiphy0/ath9k/xmit
> Num-Tx-Queues: 10  tx-queues-setup: 0x10f poll-work-seen: 7113  Off-Channel: No
>                               BE         BK        VI        VO
>
> MPDUs Queued:            77539          0         0      7717
> MPDUs Completed:         77213          0         0      7584
> MPDUs XRetried:            326          0         0       133
> Aggregates:             391465          0         0         0
> AMPDUs Queued HW:         1080          0         0         0
> AMPDUs Queued SW:       588156          0         0         0
> AMPDUs Completed:       503120          0         0         0
> AMPDUs Retried:        1033333          0         0         0
> AMPDUs XRetried:         85992          0         0         0
> FIFO Underrun:               0          0         0         0
> TXOP Exceeded:               0          0         0         0
> TXTIMER Expiry:              0          0         0         0
> DESC CFG Error:              0          0         0         0
> DATA Underrun:               0          0         0         0
> DELIM Underrun:              0          0         0         0
> TX-Pkts-All:            666651          0         0      7717
> TX-Bytes-All:        816440297          0         0    633824
> hw-put-tx-buf:          952507          0         0      5766
> hw-tx-start:                 0          0         0         0
> hw-tx-proc-desc:             0          0         0         0
> TX-Failed:                   0          0         0         0
> txq-memory-address:   f6bc1df0   f6bc1e8c  f6bc1d54  f6bc1cb8
> axq-qnum:                    2          3         1         0
> axq-depth:                   2          0         0         0
> axq-ampdu_depth:             2          0         0         0
> axq-stopped                  1          0         0         0
> tx-in-progress               0          0         0         0
> pending-frames             123          0         0         0
> txq_headidx:                 3          0         0         6
> txq_tailidx:                 3          0         0         6
> axq_q empty:                   1          1         1         1
> axq_acq empty:                 0          1         1         1
> txq_fifo[0] empty:             1          1         1         1
> txq_fifo[1] empty:             0          1         1         1
> txq_fifo[2] empty:             0          1         1         1
> txq_fifo[3] empty:             1          1         1         1
> txq_fifo[4] empty:             1          1         1         1
> txq_fifo[5] empty:             1          1         1         1
> txq_fifo[6] empty:             1          1         1         1
> txq_fifo[7] empty:             1          1         1         1
> txq[2] first-ac: f3da7a00 sched: 1
>    first-tid: f3da73c8 sched: 1 paused: 0
>


-- 
Ben Greear <greearb@candelatech.com>
Candela Technologies Inc  http://www.candelatech.com