On Wed, 11 May 2016, Toke Høiland-Jørgensen wrote: > David Lang writes: > >>> - How to measure the results? Can we dump the information from the >>> driver (and is it accurate)? Do we need to parse aircaps? Something >>> else? >> >> we need to be able to instrament the driver (I don't know if we can >> get enough data there or not currently) >> >> trying to work with aircaps has the problem that what you see in the >> aircap doesn't match what either the sender or receiver sees >> >> Take retransmissions as an example. They only happen because the >> receiver didn't see them. If you were to get an aircap off the same >> antenna as the receiver, you also wouldn't see them and therefor could >> not account for them. In the real world, you are doing the aircap from >> a different device, with a different antenna so what you see will be >> even more different. Now think about the normal case where you have >> two stations taking in two very different locations and one device to >> do the aircap. >> >> If we don't have anything else, aircaps are what we have to fall back >> on, but we need to realize how much we can't see at that point. > > Hmm, hadn't thought of that. Damn. Well, guess we'll have to trust the > driver (or make it trustworthy if we can't). the good news is that getting this information out of the driver should not be hard. It knows when it does a retransmit. I also suspect that we could get away without explictly tracking retransmits for now. As it retransmits to a station, it's also going to end up slowing down if it's a long-term problem. we need to think of the scale we are trying to be fair on. I think that if we are fair on the scale of seconds we will gain 80% of the effect that we would get if we were trying to be fair on the order of ms, and it's much easier to do :-) David Lang