Re: [Madwifi-users] Transmit-timeouts

[Andrew G. <aga...@sk...>]

Michael Gernoth wrote:
> On Fri, Apr 30, 2004 at 11:20:13AM -0500, Andrew Gaffney wrote:
> 
>>Michael Gernoth wrote:
>>
>>>[transmit timeouts with newest cvs-snapshot]
>>
>>I've experienced different variations of this bug with all the versions 
>>that I've tried (CVS from 2-18 through CVS from yesterday). With the 2-18 
>>CVS, I didn't get the 'NETDEV WATCHDOG' messages, but my connections would 
>>stall for 5 seconds every 10 to 15 seconds.
> 
> Ok, let's see:
> The downgraded version:
> marvin [~]> ping -c 200 ap1000
> ...
> 200 packets transmitted, 200 packets received, 0% packet loss
> round-trip min/avg/max = 1.8/2.0/17.7 ms
> 
> Now the up-to-date cvs:
> marvin [~]> ping -c 200 ap1000
> ...
> NETDEV WATCHDOG: ath0: transmit timed out
> 64 bytes from 192.168.100.23: icmp_seq=20 ttl=255 time=9003.7 ms
> 64 bytes from 192.168.100.23: icmp_seq=21 ttl=255 time=8004.3 ms
> 64 bytes from 192.168.100.23: icmp_seq=22 ttl=255 time=7005.4 ms
> 64 bytes from 192.168.100.23: icmp_seq=23 ttl=255 time=6007.3 ms
> 64 bytes from 192.168.100.23: icmp_seq=24 ttl=255 time=5007.4 ms
> 64 bytes from 192.168.100.23: icmp_seq=25 ttl=255 time=4010.1 ms
> 64 bytes from 192.168.100.23: icmp_seq=26 ttl=255 time=3011.4 ms
> 64 bytes from 192.168.100.23: icmp_seq=27 ttl=255 time=2012.7 ms
> 64 bytes from 192.168.100.23: icmp_seq=28 ttl=255 time=1014.4 ms
> ...
> NETDEV WATCHDOG: ath0: transmit timed out
> 64 bytes from 192.168.100.23: icmp_seq=116 ttl=255 time=8006.3 ms
> 64 bytes from 192.168.100.23: icmp_seq=117 ttl=255 time=7007.0 ms
> 64 bytes from 192.168.100.23: icmp_seq=118 ttl=255 time=6010.9 ms
> 64 bytes from 192.168.100.23: icmp_seq=119 ttl=255 time=5012.5 ms
> 64 bytes from 192.168.100.23: icmp_seq=120 ttl=255 time=4016.8 ms
> 64 bytes from 192.168.100.23: icmp_seq=121 ttl=255 time=3020.2 ms
> 64 bytes from 192.168.100.23: icmp_seq=122 ttl=255 time=2023.7 ms
> 64 bytes from 192.168.100.23: icmp_seq=123 ttl=255 time=1025.8 ms
> ...
> 200 packets transmitted, 200 packets received, 0% packet loss
> round-trip min/avg/max = 1.8/407.9/9003.7 ms

With the 2-18 CVS, running 'ping -c 100 192.168.0.x', it would get no replies for 7 
packets, then it would get replies for 14, then no replies for 7, repeating until 100. I'd 
end up with a constant 37% packet loss.

The current CVS will get no reply to 7, 7 replies will come through, then I get a bunch of 
'sendmsg: No space in the buffer' messages or something similar.

>>With the later versions from CVS, I do get the 'NETDEV WATCHDOG' message 
>>and the card seems to scan through all the channels before locking back on 
>>my AP's channel during the cutouts. I've been told it does this because of 
>>low signal strength, but this happens like clockwork even with a signal 
>>strength of 58/94.

-- 
Andrew Gaffney
Network Administrator
Skyline Aeronautics, LLC.
636-357-1548