FreeBSD-8.0 802.11n support with ath/mwl
lists at pingle.org
Sun Mar 7 21:28:41 UTC 2010
On 3/7/2010 3:34 PM, Sam Leffler wrote:
> Not following the wlanX naming convention will cause confusion for
> things like rc config files (I believe). Definitely any tool I touched
> expects vap's to be named wlanX.
Duly noted. I wasn't aware of just how many issues would arise from
straying from that convention.
> sysctl net.wlan.X.%parent gives the parent ifnet of a vap; I've
> considered many times including this in the ifconfig status. Feel free
> to offer a patch that does this.
That may be handy in the future. My C skills are a bit rusty but if I
decide to go down that road I'll surely share any patches I might come
> mwl 11n support broke sometime near the last firmware update and I never
> fixed it. I know in particular there are issues with AMPDU and seq#'s
> but possible other things too. The fw is rather finicky in how state is
> managed and it's likely the host is not in sync causing problems w/ the
> ampdu support and rate control algorithm that both operate in the fw.
> You should be able to get >100 Mb/s througput on an HT40 channel but I
> think I was seeing more like 35-40. Turning off ampdu is usually
> helpful to stabilize operation.
I'll have to try that next chance I get. I did manage to get more
antenna pigtails and now have a total of three attached, but it didn't
make a difference. A colleague was able to get an N rate association on
his mwl card (108Mbps) with similar settings to mine, but with a
different client card. It would seem that the problem may lie in the
client card in my case, so I'm also investigating options there at the
moment. It's an Intel ABGN 5100 card, in case anyone wonders.
I also found the mwlstats and mwldebug programs which are in the src
tree but not built with the system. A simple "cd
/usr/src/tools/tools/mwl; make all install" built them, but mwldebug
didn't seem to work for me. Looking at the code I just need to build a
kernel or module while having MWL_DEBUG defined to get the sysctls to
show up, but I have not yet tried that as I've had a fairly busy week.
I'll see if changing the ampdu settings make any difference and report
back, and hopefully the rebuild with MWL_DEBUG might also help me get a
lead if tweaking ampdu doesn't help.
Thanks for the reply, Sam. I appreciate the insight.
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