More 'resource' problems with "ath0"

[Sam Leffler]

Ross Finlayson wrote:
> 
>> Are any of the stations associated to these systems operating in power
>> save mode?
> 
> No, I don't use power save mode.  (One of the servers is at home, where
> all of its clients are plugged in to AC power.  The other server is at a
> local coffee shop, where the owner wants to discourage people from
> camping there for hours :-)

Er, we're talking about wireless operation here, not acpi or similar.
If the stations associated to the ap are operating in power save mode
then they periodically put their wireless h/w into a power-saving sleep
mode to reduce the drain on the battery.  In this mode the ap has to
buffer frames for the client.  I'm aware of one outstanding issue with
this mode whereby frames (apparently) can be stuck on the buffering q
because the beacon frame stops being transmitted.  This problem is
currently unresolved (however you would also see messages on the ap
about "transmit timeout").

I don't recall if stations associated with power save are marked in the
display shown by

ifconfig ath0 list sta

If not then turning on power debug msgs at the 802.11 layer with
wlandebug; e.g.

wlandebug -i ath0 power

will definitely show whether any are present (use wlandebug -i ath0 0
after to reset).

> 
>>  Is there some reason you have the cards locked to 11b?  If
>> not, you should be able to let them operate in 11g.
> 
> In each case, the back-end Internet connection is only 1.5 Mbps, so the
> extra bitrate of 11g was not needed.  However, on your suggestion, I'll
> try running both servers at 11g now.

It should not matter but 11g is the typical usage and if clients are
confused by being forced to operate in 11b the problem may go away.

	Sam