> According to the documentation, > - tx_failed is the "number of failed transmissions (retries exceeded, no ACK)". > - tx_retries is the "cumulative retry counts". > > Since the default number of retries seems to be 7, I would expect tx_retries to be at least 7 times tx_failed. However, on my computer tx_retries is about 20 times **less** tx_failed. This doesn't make sense to me. Shouldn't the tx_failed counter increment only after a certain number of retries? And therefore be less than tx_retries? The default number of retries is 16. The reason you have odd numbers is because we don't report this properly. The big problem is about AMPDU mainly - the frames are picked up by the HW and retransmissions are handled by the FW / HW. While we know how many packets failed vs. how many were sent (for rate control purposes), we can't know exactly what frame we retransmitted and how many times (well... we can - but it is not trivial). Since the the only way to tell mac80211 / cfg80211 / iw is per-packet (in ieee80211_tx_status in each Tx status for each packet), the information there is not accurate. I want to hope that if you disabled AMPDU (Tx) you'll get more accurate results - I haven't tested myself though. -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
