I did some more digging on this.
- by setting distance to 'indoors' I can improve throughput a bit but still not excellent
- throughput is heavily asymmetric (downlink faster than uplink)
I notice that I'm not the only one, there are similar reports:
(I realise that many people had problems because the encryption was not set to WPA2, mine is WPA2).
I tried some suggestions from the topics above:
1) setting the distance to 'indoors' (seems to improve uplink throughput by ~10Mbps)
2) reducing the hw-retries (doesn't seem to make a big difference)
3) there are suggestions that mikrotik performance is poor on a single TCP stream but good on 10+. Running 20 streams seems to improve throughput by ~10Mbps.
Test methodology: I'm using "iperf -P 20 -c <wired_host> -r -t 60"
(20 parallel streams, testing both tx and rx one after the other)
Results (bandwidth order is STA->AP Mbps / AP->STA Mbps):
- UniFi running 802.11n for comparison: 74 / 73
- MT with "distance=dynamic": 36 / 73
- MT with "distance=indoors": 44 / 76
- MT with "distance=indoors", single TCP stream: 37 / 68
So the best I can do is roughly equal to the UniFi on AP->STA but just about half the UniFi's throughput STA->AP.
I really really want to use the MT because the interface and tools are so much better, but not if there's a big performance disadvantage -- does anyone have any other suggestions of things to try?