On Jul 18, 2013, at 11:22 AM, Adrian Chadd <[email protected]> wrote:
> On Jul 18, 2013, at 11:19 AM, Petar Bogdanovic <[email protected]> wrote: > >> On Thu, Jul 18, 2013 at 09:25:19AM -0700, Adrian Chadd wrote: >>> On 18 July 2013 09:04, Petar Bogdanovic <[email protected]> wrote: >>>> On Thu, Jul 18, 2013 at 08:59:29AM -0700, Adrian Chadd wrote: >>>>> >>>>> I think I fixed this in -HEAD. >>>> >>>> Uh-oh, great! Will that change reach a stable release anytime soon? >>> >>> When 10.0 is stable, yup. :) >>> >>>> And--out of naive curiosity--what was the problem? >>> >>> The ath driver before 11n support went in would just fill the hardware >>> TX queue with frames. There's no per-station queue or any kind of fair >>> queuing. So if you fill the TX queue in the driver with frames to a >>> far away station, it'll block all frames to other stations whilst >>> they're transmitted and retransmitted. >>> >>> When I introduced 11n support, I added per-station and >>> per-traffic-class queues in the driver as part of A-MPDU support. I >>> software queue almost everything first and then schedule frames to the >>> hardware from these software queued frames. This has the side effect >>> of making it fairer between multiple stations, especially if one of >>> them is far away. It will only schedule a small number of frames to >>> each station before going to another station, rather than possibly >>> being backed up with 128 frames just to a single destination. >>> >>> Now, it's likely there's more work that can be done to improve that >>> behaviour with slow, far away clients. The framework is there in >>> -HEAD. I've just not sat down and made it work. So if you update to >>> -HEAD and you still have problems, we can tweak things and experiment. >> >> Thanks for the nice and comprehensive explanation! >> >> I'll prepare the upgrade during the next couple of weeks and report >> back. It will probably be 9.1 userland and HEAD kernel (that approach >> worked well in the past). > > I really do suggest -HEAD everything. If it makes you feel any better, I've been running -HEAD (with semi-regular updates) on my ALIX AP for a while without any trouble. Of course, I do the builds on another box... I'm happy to share make settings, etc if that would be useful. JN _______________________________________________ [email protected] mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-wireless To unsubscribe, send any mail to "[email protected]"
