On Sunday, 9 June 2019 20:45:06 HKT René Treffer wrote:
I am testing this on devices with ath9k (2.4GHz) and ath10k (5GHz), so I was looking at the estimates I get from ath9k. Here is a dump from my
home network on 2.4GHz/ath9k and what rx/3 would give us:
signal tx rx expect tx/3 min(tx/3,(rx+tx)/2/3) -77 13.0 43.3 6.682 4.333 -57 130.0 117.0 44.677 43.333 41.166 -53 117.0 130.0 42.388 39.0 -82 43.3 6.5 13.366 14.433 8.3 (!!!) -63 52.0 86.7 26.733 17.333 -58 130.0 173.3 29.21 43.333 !!! -82 6.5 43.3 2.197 2.166 -48 104.0 65.0 40.191 34.666 28.166 -69 57.8 13.0 20.49 19.266 11.8 -58 86.7 52.0 33.507 28.9 23.116 -58 52.0 1.0 37.994 17.333 8.833 -56 115.6 144.4 29.21 38.533 !!!
To confirm my understanding: What this table shows are raw tx/rx link estimated values ? None of these numbers compares to Minstrel HT expected throughput or actual throughput ?
Cases where the rx/tx estimate would be higher are marked with !!!.
I also don't quite understand what the '!!!' thing is trying to indicate. What is being compared ? But it may be due to my misunderstandings above.
In my small test setup with one ath10k device meshing with ath9k over 2.4GHz, your tx / 3 formula seems to be quite accurate (had removed the rx part).
# batctl o (your magic formula) * ac:86:74:00:38:06 0.930s ( 45.7) ac:86:74:00:38:06 [ mesh24]
# batctl tp ac:86:74:00:38:06 (actual throughput) Test duration 10440ms. Sent 58393512 Bytes. Throughput: 5.33 MB/s (44.75 Mbps)
What would be interesting is how the numbers produced by 'tx / 3' compare to either the actual throughput (can easily be tested with the throughput meter) or Minstrel expected throughput.
Why bother and look at rx at all? Asymmetric routing should already work. I was bit concerned about highly asymmetric links, especially those where the path back might not work. It might not be worth it though.
Generally, the return path might be entirely different. Batman-adv does not enforce or even endorse symetric paths. If there is better path for the return route, batman-adv will choose the better path based on tx from the sender and if only one return path exists, we don't care anyway ..
Cheers, Marek