[Cerowrt-devel] the iwl driver sucks

Dave Taht dave.taht at gmail.com
Sun Dec 9 12:18:34 EST 2012


I am happy to report that ad-hoc mode (used by cero in mesh networking
mode) still works in 3.6.9-5.

On the other hand the iwl driver in linux 3.6.8 is nearly unusable in
paris, generically, on my laptop. I have no idea why, I just want to
get an ath9k chip into it so I don't have to deal with it.... (it
takes 2 minutes or more to send an email via google, IF it succeeds.
I'm now 10 minutes into downloading richard's preso with only 320k
downloaded so far)

I did some rrul experiments on the adhoc interfaces today that were
very interesting.

One result was that in good conditions I'd get 100Mbit total,
bidirectionally, with rrul, with ath9k set to 128 packets, and could
see tcp global synchronization with pfifo fast, and fq_codel had very
little visible effect. uploads were at about 82Mbit and down 24. ~30ms
median RTT latency. I also saw a really neat one where BE and BK
traffic underwent priority inversion for a while.

With ath9k set to 2, and fq_codel I'd get about 16/13 and ~10ms median
RTT latency. So... far less throughput, but a vastly better up/down
ratio - and far less latency.

under bad conditions (router in the microwave for shielding), oh...
my... god... at 128 ath9k buffers... I don't want to talk about it.

-- 
Dave Täht

Fixing bufferbloat with cerowrt: http://www.teklibre.com/cerowrt/subscribe.html



More information about the Cerowrt-devel mailing list