Subject: Re: atheros 5212 card in adhoc mode and "no buffer space"
To: Konstantin KABASSANOV <Konstantin.Kabassanov@lip6.fr>
From: David Young <dyoung@pobox.com>
List: tech-net
Date: 05/23/2004 21:37:55
On Fri, May 21, 2004 at 03:51:03PM +0200, Konstantin KABASSANOV wrote:
> > -----Original Message-----
> > From: tech-net-owner@NetBSD.org [mailto:tech-net-owner@NetBSD.org] On
> > Behalf Of Konstantin Kabassanov
> > Sent: mardi 11 mai 2004 12:00
> > To: David Young
> > Cc: tech-net@NetBSD.org
> > Subject: Re: atheros 5212 card in adhoc mode and "no buffer space"
> > 
> > Dave,
> > 
> > Sorry for the delayed answer.
> > 
> > The bogus xmit rate has gone. Thanks.
> > Concerning the message "no buffer space", I can still see it when I
> use
> > iperf on both PCs (with WG511T carss) and try to send traffic over
> 6Mbps.
> > 
> > I observed the following bugs with Netgear WAG511.  Adhoc mode is not
> > working if I don't limit the media to less or
> > OFDM24. If I do so, I need to put the interface corresponding to the
> BSSID
> > down and bring it up again, because if I don't do this, it still
> announces
> > all available rates. The "write failed: no buffer space available"
> > reappeares as for WG511T, but for WAG511 cards, that occurs if the
> traffic
> > goes over 600K !!!
> > 
> > When trying to use 3CRPAG175 cards in adhoc mode it doesn't work at
> all.
> > 
> > Generally I have always the following message: ath0: unable to reset
> > hardware; hal status 3 if I try to modify an interface parameter when
> the
> > interface is up. ifconfig ath0 down and ifconfiga ath0 up solves the
> > problem.
> > 
> > Concerning the multihop wireless networks, you are right I'm working
> in
> > this domain. I'm not really sure that ath-type hardware does a proper
> IBSS
> > merge. I'm actually testing ... That could be the explanation for the
> > 3CRPAG175 problems...
> > 
> > Konstantin
> 
> Dave,
> 
> The only comment I saw concerning my last mail, was sam's reply about
> the IBSS merge. I'm really scared by the network performances of the
> adhoc mode and I'm asking myself if it is a generic driver problem or it
> is a hardware issue. In addition I think it would not be very hard to
> modify the master bssid node's behavior in order to set the right media
> transmission rate without shutting down and giving up again its network
> interface... What do you think about?

Konstantin,

I don't know if it helps, but there is no such thing as a "master"
IBSS node.

Please compile with "options IEEE80211_DEBUG."  Set
net.link.ieee80211.debug = 1 with sysctl.  Tell me what else is logged
when the "no buffer space available" message appears.  I am especially
curious whether your ath(4) starts to scan channels....

Dave

-- 
David Young             OJC Technologies
dyoung@ojctech.com      Urbana, IL * (217) 278-3933