On Wed, 2007-12-05 at 08:49 +0100, Holger Schurig wrote: > On Tuesday 04 December 2007 23:05:28 Nick Kossifidis wrote: > > [ 3] 0.0-60.0 sec 29.4 MBytes 4.11 Mbits/sec 3.242 ms > > [ 3] 0.0-60.0 sec 29.4 MBytes 4.11 Mbits/sec 4.439 ms > > [ 3] 0.0-60.0 sec 32.7 MBytes 4.57 Mbits/sec > ... > > > Could it be the case that if we test the PID controller such way, > then we optimize for throughtput in a scenario like "laptop sits > next the the AP". > > Or, in other words: if we put the AP 80m away and then try the > test, would the same PID parameters that yielded high MB/s rates > now still keep us a sane (for that distance!) connection? Good question. The important parameter here is the failed frames precentage target value. If we're sitting next to the AP, the percentage of failed frames will be very low, so the PID controller won't ever be able to tune the TX rate to increase the failed frames percentage to the target value. So this is not the right test case for tuning PID rate control parameters. It'd be interesting to find out about the failed frames percentage target value that gives us the best throughput. And then do this experiment several times for different levels of distance (or noise). Then see whether the optimal value is constant or not. At the moment, I'm still cleaning up the rate control code. I also plan to add some debugfs support, so we can retrieve the relevant data from the kernel and make graphs from them. Only when this is done, I'm gonna resume tuning parameters. Mattias - To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
