Re: AR5001X+ connections freeze on heavy transfers

On Thu, 4 Nov 2010 20:24:37 -0400, Dennis Nezic wrote:
> When I do heavy transfers (500+ mb), regardless of the protocol (NFS,
> http, scp, etc), after a non-predictable time the transfers usually
> freeze. Strangely, however, I can still happily ping the machine and
> ssh into it -- only the main transfer seems affected. The only remedy
> seems to be to unload/reload ath_pci. (I haven't seen this problem
> between any of my non-madwifi machines.)
> 
> Currently I'm using madwifi-ng-0.9.4.4133.20100621 and linux kernel
> 2.6.36, although I've had this problem for a while.
> 
> I'm using the default ath_rate_sample. Perhaps I should try the
> others? Perhaps I should provide more (rate)stats too :P.
> 
> It's probably related to http://madwifi-project.org/ticket/1790

None of the ath_rate_* algorithms fix the problem. (Minstrel performs
far better than the others, but eventually succumbs.)

Here are two athstats, using ath_rate_sample, taken 50minutes apart,
during a large continuous nfs file transfer:

422 tx management frames
169236 tx frames discarded due to queue depth
237 tx failed due to too many retries
121886 long on-chip tx retries
65 tx frames with no ack marked
1023541 tx frames with short preamble
21649 tx frames with an alternate rate
20515 rx failed due to bad CRC
108749 PHY errors
    4505 OFDM timing
    33 OFDM restart
    104010 CCK timing
    201 CCK restart
385 periodic calibrations
rssi of last ack: 26
rssi of last rcv: 29
1 switched default/rx antenna
Antenna profile:
[1] tx   512925 rx    99313
[2] tx   510788 rx      174

[48minutes later...]

901 tx management frames
263728 tx frames discarded due to queue depth
1053 tx failed due to too many retries
221105 long on-chip tx retries
66 tx frames with no ack marked
1660431 tx frames with short preamble
43636 tx frames with an alternate rate
23781 rx failed due to bad CRC
174894 PHY errors
    7282 OFDM timing
    33 OFDM restart
    167365 CCK timing
    214 CCK restart
480 periodic calibrations
rssi of last ack: 23
rssi of last rcv: 25
1 switched default/rx antenna
Antenna profile:
[1] tx   833189 rx   163656
[2] tx   827077 rx      271


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