Friday, June 15, 2012

Don't let anyone tell you that FreeBSD doesn't "do" 802.11n:

This is from my FreeBSD-HEAD 802.11n access point, currently doing ~ 130MBit/s TCP:

# athstats -i ath0
41838297     data frames received
31028383     data frames transmit
78260        short on-chip tx retries
3672         long on-chip tx retries
197          tx failed 'cuz too many retries
MCS13        current transmit rate
8834         tx failed 'cuz destination filtered
477          tx frames with no ack marked
239517       rx failed 'cuz of bad CRC
10           rx failed 'cuz of PHY err
    10           OFDM restart
42043        beacons transmitted
143          periodic calibrations
-0/+0        TDMA slot adjust (usecs, smoothed)
45           rssi of last ack
51           avg recv rssi
-96          rx noise floor
812          tx frames through raw api
41664029     A-MPDU sub-frames received
42075948     Half-GI frames received
42075981     40MHz frames received
13191        CRC errors for non-last A-MPDU subframes
129          CRC errors for last subframe in an A-MPDU
2645042      Frames transmitted with HT Protection
351457       Number of frames retransmitted in software
23299        Number of frames exceeding software retry
30674735     A-MPDU sub-frame TX attempt success
374408       A-MPDU sub-frame TX attempt failures
8676         A-MPDU TX frame failures
443          listen time
6435         cumulative OFDM phy error count
161          ANI forced listen time to zero
3672         missing ACK's
78260        RTS without CTS
1469003      successful RTS
239605       bad FCS
2            average rssi (beacons only)
Antenna profile:
[0] tx  1466665 rx        1
[1] tx        0 rx 41838296


  1. I'm sorry, I have a small question: will it be in stable-9?

  2. I have no plans to merge the ath(4) support into -9. The changes are really quite large. I needed to rearchitect the entire TX path.