Bechmark results between MT76 open source and "stock" Mediatek on MT7612e and MT7603e

I did some benchmarking between the MT76 open source driver and a patched original Mediatek driver. Interesting is that especially on the MT7612e WLAN -> LAN is much better then the "stock" driver. However, where it matters for most of us (I think) is from LAN (WAN) to WLAN. there the open source driver is much worst. Hopefully the Kernel Driver Guru's figure out soon how to improve this situation.

Router receiving - MT76 - mt76x2 (mt7612e) opensource driver (Lede 4.9.40)
WLAN laptop to Wired Mac-mini (Single Stream)
-----------------------------------------------------------
Server listening on 5201
-----------------------------------------------------------
Accepted connection from 192.168.1.198, port 28067
[  5] local 192.168.1.188 port 5201 connected to 192.168.1.198 port 28068
[ ID] Interval           Transfer     Bandwidth
[  5]   0.00-1.00   sec  37.5 MBytes   315 Mbits/sec              
[  5]   1.00-2.00   sec  41.8 MBytes   350 Mbits/sec              
[  5]   2.00-3.00   sec  43.1 MBytes   362 Mbits/sec              
[  5]   3.00-4.00   sec  40.8 MBytes   342 Mbits/sec              
[  5]   4.00-5.00   sec  40.9 MBytes   343 Mbits/sec              
[  5]   5.00-6.00   sec  39.9 MBytes   334 Mbits/sec              
[  5]   6.00-7.00   sec  41.5 MBytes   347 Mbits/sec              
[  5]   7.00-8.00   sec  41.6 MBytes   351 Mbits/sec              
[  5]   8.00-9.00   sec  38.6 MBytes   324 Mbits/sec              
[  5]   9.00-10.00  sec  42.0 MBytes   352 Mbits/sec              
[  5]  10.00-10.05  sec  1.88 MBytes   315 Mbits/sec              
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval           Transfer     Bandwidth
[  5]   0.00-10.05  sec   410 MBytes   342 Mbits/sec              sender
[  5]   0.00-10.05  sec   410 MBytes   342 Mbits/sec              receiver
-----------------------------------------------------------
Server listening on 5201
-----------------------------------------------------------

To push to maximum throughput: 8 Parallel streams:
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval           Transfer     Bandwidth
[  5]   0.00-10.03  sec   100 MBytes  83.7 Mbits/sec              sender
[  5]   0.00-10.03  sec   100 MBytes  83.7 Mbits/sec              receiver
[  7]   0.00-10.03  sec  94.6 MBytes  79.2 Mbits/sec              sender
[  7]   0.00-10.03  sec  94.6 MBytes  79.2 Mbits/sec              receiver
[  9]   0.00-10.03  sec  97.4 MBytes  81.5 Mbits/sec              sender
[  9]   0.00-10.03  sec  97.4 MBytes  81.5 Mbits/sec              receiver
[ 11]   0.00-10.03  sec  90.9 MBytes  76.0 Mbits/sec              sender
[ 11]   0.00-10.03  sec  90.9 MBytes  76.0 Mbits/sec              receiver
[ 13]   0.00-10.03  sec  92.8 MBytes  77.6 Mbits/sec              sender
[ 13]   0.00-10.03  sec  92.8 MBytes  77.6 Mbits/sec              receiver
[ 15]   0.00-10.03  sec  92.0 MBytes  77.0 Mbits/sec              sender
[ 15]   0.00-10.03  sec  92.0 MBytes  77.0 Mbits/sec              receiver
[ 17]   0.00-10.03  sec  88.0 MBytes  73.6 Mbits/sec              sender
[ 17]   0.00-10.03  sec  88.0 MBytes  73.6 Mbits/sec              receiver
[ 19]   0.00-10.03  sec  88.9 MBytes  74.4 Mbits/sec              sender
[ 19]   0.00-10.03  sec  88.9 MBytes  74.4 Mbits/sec              receiver
[SUM]   0.00-10.03  sec   744 MBytes   623 Mbits/sec              sender
[SUM]   0.00-10.03  sec   744 MBytes   623 Mbits/sec              receiver
-----------------------------------------------------------



Router Sending - MT76 - mt76x2 (mt7612e) opensource driver (Lede 4.9.40)
Wired Mac-mini to WLAN laptop
 
Connecting to host 192.168.1.198, port 5201
[  4] local 192.168.1.188 port 63168 connected to 192.168.1.198 port 5201
[ ID] Interval           Transfer     Bandwidth
[  4]   0.00-1.03   sec  6.12 MBytes  50.0 Mbits/sec              
[  4]   1.03-2.02   sec  6.25 MBytes  52.9 Mbits/sec              
[  4]   2.02-3.02   sec  5.62 MBytes  47.1 Mbits/sec              
[  4]   3.02-4.01   sec  6.12 MBytes  52.0 Mbits/sec              
[  4]   4.01-5.01   sec  6.62 MBytes  55.5 Mbits/sec              
[  4]   5.01-6.03   sec  6.25 MBytes  51.5 Mbits/sec              
[  4]   6.03-7.01   sec  6.00 MBytes  51.4 Mbits/sec              
[  4]   7.01-8.00   sec  5.88 MBytes  49.5 Mbits/sec              
[  4]   8.00-9.01   sec  6.25 MBytes  52.1 Mbits/sec              
[  4]   9.01-10.01  sec  6.00 MBytes  50.2 Mbits/sec              
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval           Transfer     Bandwidth
[  4]   0.00-10.01  sec  61.1 MBytes  51.2 Mbits/sec              sender
[  4]   0.00-10.01  sec  61.0 MBytes  51.1 Mbits/sec              receiver

iperf Done.

Multiple streams will only give lower throughput

[code]Lede 4.4.79 Kernel with patched MT76x2e (MT7612e) original Mediatek driver
WLAN laptop to Wired Mac-mini

iperf3 -s

Server listening on 5201

Accepted connection from 192.168.1.198, port 26057
[ 5] local 192.168.1.188 port 5201 connected to 192.168.1.198 port 26058
[ ID] Interval Transfer Bandwidth
[ 5] 0.00-1.00 sec 29.0 MBytes 243 Mbits/sec
[ 5] 1.00-2.00 sec 36.2 MBytes 304 Mbits/sec
[ 5] 2.00-3.00 sec 37.2 MBytes 312 Mbits/sec
[ 5] 3.00-4.00 sec 32.9 MBytes 276 Mbits/sec
[ 5] 4.00-5.00 sec 35.0 MBytes 293 Mbits/sec
[ 5] 5.00-6.00 sec 38.9 MBytes 326 Mbits/sec
[ 5] 6.00-7.00 sec 36.8 MBytes 308 Mbits/sec
[ 5] 7.00-8.00 sec 36.9 MBytes 309 Mbits/sec
[ 5] 8.00-9.00 sec 36.9 MBytes 310 Mbits/sec
[ 5] 9.00-10.00 sec 38.6 MBytes 324 Mbits/sec
[ 5] 10.00-10.05 sec 2.00 MBytes 338 Mbits/sec


[ ID] Interval Transfer Bandwidth
[ 5] 0.00-10.05 sec 360 MBytes 301 Mbits/sec sender
[ 5] 0.00-10.05 sec 360 MBytes 301 Mbits/sec receiver

Server listening on 5201

Pushed to the maximum with 6 streams:


[ ID] Interval Transfer Bandwidth
[ 5] 0.00-10.04 sec 103 MBytes 85.7 Mbits/sec sender
[ 5] 0.00-10.04 sec 103 MBytes 85.7 Mbits/sec receiver
[ 7] 0.00-10.04 sec 100 MBytes 83.8 Mbits/sec sender
[ 7] 0.00-10.04 sec 100 MBytes 83.8 Mbits/sec receiver
[ 9] 0.00-10.04 sec 97.1 MBytes 81.1 Mbits/sec sender
[ 9] 0.00-10.04 sec 97.1 MBytes 81.1 Mbits/sec receiver
[ 11] 0.00-10.04 sec 95.0 MBytes 79.3 Mbits/sec sender
[ 11] 0.00-10.04 sec 95.0 MBytes 79.3 Mbits/sec receiver
[ 13] 0.00-10.04 sec 92.5 MBytes 77.3 Mbits/sec sender
[ 13] 0.00-10.04 sec 92.5 MBytes 77.3 Mbits/sec receiver
[ 15] 0.00-10.04 sec 90.6 MBytes 75.7 Mbits/sec sender
[ 15] 0.00-10.04 sec 90.6 MBytes 75.7 Mbits/sec receiver
[SUM] 0.00-10.04 sec 578 MBytes 483 Mbits/sec sender
[SUM] 0.00-10.04 sec 578 MBytes 483 Mbits/sec receiver

Lede kernel 4.4.79 with patched MT76x2e (MT7612e) original Mediatek driver
Wired Mac-mini to WLAN laptop

iperf3 -c 192.168.1.198
Connecting to host 192.168.1.198, port 5201
[ 4] local 192.168.1.188 port 58445 connected to 192.168.1.198 port 5201
[ ID] Interval Transfer Bandwidth
[ 4] 0.00-1.00 sec 27.6 MBytes 231 Mbits/sec
[ 4] 1.00-2.00 sec 31.8 MBytes 267 Mbits/sec
[ 4] 2.00-3.00 sec 33.4 MBytes 279 Mbits/sec
[ 4] 3.00-4.01 sec 33.9 MBytes 283 Mbits/sec
[ 4] 4.01-5.00 sec 35.6 MBytes 300 Mbits/sec
[ 4] 5.00-6.00 sec 36.6 MBytes 307 Mbits/sec
[ 4] 6.00-7.01 sec 35.6 MBytes 297 Mbits/sec
[ 4] 7.01-8.01 sec 27.9 MBytes 235 Mbits/sec
[ 4] 8.01-9.00 sec 35.0 MBytes 294 Mbits/sec
[ 4] 9.00-10.00 sec 36.1 MBytes 303 Mbits/sec


[ ID] Interval Transfer Bandwidth
[ 4] 0.00-10.00 sec 334 MBytes 280 Mbits/sec sender
[ 4] 0.00-10.00 sec 333 MBytes 280 Mbits/sec receiver

iperf Done.

Pushing to the maximum with 7 streams:


[ ID] Interval Transfer Bandwidth
[ 4] 0.00-10.01 sec 81.2 MBytes 68.1 Mbits/sec sender
[ 4] 0.00-10.01 sec 81.2 MBytes 68.1 Mbits/sec receiver
[ 6] 0.00-10.01 sec 81.2 MBytes 68.1 Mbits/sec sender
[ 6] 0.00-10.01 sec 81.2 MBytes 68.1 Mbits/sec receiver
[ 8] 0.00-10.01 sec 81.2 MBytes 68.1 Mbits/sec sender
[ 8] 0.00-10.01 sec 81.2 MBytes 68.1 Mbits/sec receiver
[ 10] 0.00-10.01 sec 81.2 MBytes 68.1 Mbits/sec sender
[ 10] 0.00-10.01 sec 81.2 MBytes 68.0 Mbits/sec receiver
[ 12] 0.00-10.01 sec 81.2 MBytes 68.1 Mbits/sec sender
[ 12] 0.00-10.01 sec 81.2 MBytes 68.1 Mbits/sec receiver
[ 14] 0.00-10.01 sec 81.2 MBytes 68.1 Mbits/sec sender
[ 14] 0.00-10.01 sec 81.2 MBytes 68.0 Mbits/sec receiver
[ 16] 0.00-10.01 sec 81.2 MBytes 68.1 Mbits/sec sender
[ 16] 0.00-10.01 sec 81.2 MBytes 68.0 Mbits/sec receiver
[SUM] 0.00-10.01 sec 569 MBytes 477 Mbits/sec sender
[SUM] 0.00-10.01 sec 569 MBytes 476 Mbits/sec receiver

iperf Done.
[/code]

Router Receiving with MT76 - MT7603 open source driver (Lede 4.9.40)
WLAN laptop to Wired Mac-mini
-----------------------------------------------------------
Server listening on 5201
-----------------------------------------------------------
Accepted connection from 192.168.1.198, port 28284
[  5] local 192.168.1.188 port 5201 connected to 192.168.1.198 port 28286
[ ID] Interval           Transfer     Bandwidth
[  5]   0.00-1.00   sec  10.9 MBytes  91.1 Mbits/sec              
[  5]   1.00-2.00   sec  12.0 MBytes   101 Mbits/sec              
[  5]   2.00-3.03   sec  10.1 MBytes  82.4 Mbits/sec              
[  5]   3.03-4.06   sec  7.62 MBytes  62.5 Mbits/sec              
[  5]   4.06-5.02   sec  8.62 MBytes  75.2 Mbits/sec              
[  5]   5.02-6.02   sec  10.2 MBytes  85.8 Mbits/sec              
[  5]   6.02-7.01   sec  10.4 MBytes  87.8 Mbits/sec              
[  5]   7.01-8.02   sec  9.00 MBytes  74.8 Mbits/sec              
[  5]   8.02-9.04   sec  5.25 MBytes  43.3 Mbits/sec              
[  5]   9.04-10.02  sec  5.00 MBytes  42.5 Mbits/sec              
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval           Transfer     Bandwidth
[  5]   0.00-10.02  sec  89.2 MBytes  74.7 Mbits/sec              sender
[  5]   0.00-10.02  sec  89.1 MBytes  74.6 Mbits/sec              receiver
-----------------------------------------------------------
Server listening on 5201
----------------------------------------------------------

Pushing to the maximum with 8 streams:
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval           Transfer     Bandwidth
[  5]   0.00-10.17  sec  14.2 MBytes  11.8 Mbits/sec              sender
[  5]   0.00-10.17  sec  14.2 MBytes  11.8 Mbits/sec              receiver
[  7]   0.00-10.17  sec  14.9 MBytes  12.3 Mbits/sec              sender
[  7]   0.00-10.17  sec  14.1 MBytes  11.7 Mbits/sec              receiver
[  9]   0.00-10.17  sec  12.8 MBytes  10.5 Mbits/sec              sender
[  9]   0.00-10.17  sec  12.8 MBytes  10.5 Mbits/sec              receiver
[ 11]   0.00-10.17  sec  14.4 MBytes  11.9 Mbits/sec              sender
[ 11]   0.00-10.17  sec  14.0 MBytes  11.5 Mbits/sec              receiver
[ 13]   0.00-10.17  sec  14.9 MBytes  12.3 Mbits/sec              sender
[ 13]   0.00-10.17  sec  14.0 MBytes  11.5 Mbits/sec              receiver
[ 15]   0.00-10.17  sec  14.5 MBytes  12.0 Mbits/sec              sender
[ 15]   0.00-10.17  sec  13.6 MBytes  11.2 Mbits/sec              receiver
[ 17]   0.00-10.17  sec  13.6 MBytes  11.2 Mbits/sec              sender
[ 17]   0.00-10.17  sec  13.6 MBytes  11.2 Mbits/sec              receiver
[ 19]   0.00-10.17  sec  14.8 MBytes  12.2 Mbits/sec              sender
[ 19]   0.00-10.17  sec  13.9 MBytes  11.4 Mbits/sec              receiver
[SUM]   0.00-10.17  sec   114 MBytes  94.0 Mbits/sec              sender
[SUM]   0.00-10.17  sec   110 MBytes  90.9 Mbits/sec              receiver
-----------------------------------------------------------


Router Sending MT76-MT7603 open source driver (Lede 4.9.40)
Wired Mac-mini to WLAN laptop

Connecting to host 192.168.1.198, port 5201
[  4] local 192.168.1.188 port 63236 connected to 192.168.1.198 port 5201
[ ID] Interval           Transfer     Bandwidth
[  4]   0.00-1.07   sec  4.62 MBytes  36.3 Mbits/sec              
[  4]   1.07-2.00   sec  4.62 MBytes  41.6 Mbits/sec              
[  4]   2.00-3.11   sec  3.88 MBytes  29.2 Mbits/sec              
[  4]   3.11-4.01   sec  4.38 MBytes  40.8 Mbits/sec              
[  4]   4.01-5.00   sec  4.12 MBytes  35.0 Mbits/sec              
[  4]   5.00-6.00   sec  4.25 MBytes  35.7 Mbits/sec              
[  4]   6.00-7.02   sec  4.00 MBytes  33.0 Mbits/sec              
[  4]   7.02-8.01   sec  4.00 MBytes  33.8 Mbits/sec              
[  4]   8.01-9.02   sec  4.00 MBytes  33.4 Mbits/sec              
[  4]   9.02-10.02  sec  3.50 MBytes  29.2 Mbits/sec              
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval           Transfer     Bandwidth
[  4]   0.00-10.02  sec  41.4 MBytes  34.6 Mbits/sec              sender
[  4]   0.00-10.02  sec  41.3 MBytes  34.5 Mbits/sec              receiver

iperf Done.
Lede kernel 4.4.79 with patched MT7603e original Mediatek driver
WLAN laptop to Wired Mac-mini

-----------------------------------------------------------
Server listening on 5201
-----------------------------------------------------------
Accepted connection from 192.168.1.198, port 26147
[  5] local 192.168.1.188 port 5201 connected to 192.168.1.198 port 26148
[ ID] Interval           Transfer     Bandwidth
[  5]   0.00-1.01   sec  11.1 MBytes  92.0 Mbits/sec              
[  5]   1.01-2.01   sec  12.1 MBytes   102 Mbits/sec              
[  5]   2.01-3.00   sec  12.4 MBytes   104 Mbits/sec              
[  5]   3.00-4.00   sec  12.5 MBytes   105 Mbits/sec              
[  5]   4.00-5.00   sec  12.2 MBytes   103 Mbits/sec              
[  5]   5.00-6.01   sec  11.8 MBytes  98.0 Mbits/sec              
[  5]   6.01-7.00   sec  11.8 MBytes  99.3 Mbits/sec              
[  5]   7.00-8.01   sec  12.8 MBytes   106 Mbits/sec              
[  5]   8.01-9.00   sec  11.5 MBytes  96.8 Mbits/sec              
[  5]   9.00-10.00  sec  11.9 MBytes   100 Mbits/sec              
[  5]  10.00-10.05  sec   640 KBytes   116 Mbits/sec              
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval           Transfer     Bandwidth
[  5]   0.00-10.05  sec   121 MBytes   101 Mbits/sec              sender
[  5]   0.00-10.05  sec   121 MBytes   101 Mbits/sec              receiver
-----------------------------------------------------------


Lede Kernel 4.4.79 with patched MT7603e original Mediatek driver
Wired Mac-mini to WLAN laptop

iperf3 -c 192.168.1.198
Connecting to host 192.168.1.198, port 5201
[  4] local 192.168.1.188 port 58512 connected to 192.168.1.198 port 5201
[ ID] Interval           Transfer     Bandwidth
[  4]   0.00-1.03   sec  4.88 MBytes  39.8 Mbits/sec              
[  4]   1.03-2.01   sec  4.25 MBytes  36.3 Mbits/sec              
[  4]   2.01-3.01   sec  4.50 MBytes  37.6 Mbits/sec              
[  4]   3.01-4.04   sec  4.75 MBytes  38.9 Mbits/sec              
[  4]   4.04-5.07   sec  4.38 MBytes  35.7 Mbits/sec              
[  4]   5.07-6.03   sec  4.38 MBytes  38.2 Mbits/sec              
[  4]   6.03-7.04   sec  4.50 MBytes  37.2 Mbits/sec              
[  4]   7.04-8.04   sec  4.38 MBytes  36.8 Mbits/sec              
[  4]   8.04-9.03   sec  4.50 MBytes  38.0 Mbits/sec              
[  4]   9.03-10.03  sec  4.38 MBytes  36.6 Mbits/sec              
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval           Transfer     Bandwidth
[  4]   0.00-10.03  sec  44.9 MBytes  37.5 Mbits/sec              sender
[  4]   0.00-10.03  sec  44.8 MBytes  37.5 Mbits/sec              receiver

iperf Done.

Pushing maximum at 7 streams:
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval           Transfer     Bandwidth
[  4]   0.00-10.08  sec  7.62 MBytes  6.35 Mbits/sec              sender
[  4]   0.00-10.08  sec  7.62 MBytes  6.35 Mbits/sec              receiver
[  6]   0.00-10.08  sec  7.62 MBytes  6.35 Mbits/sec              sender
[  6]   0.00-10.08  sec  7.62 MBytes  6.34 Mbits/sec              receiver
[  8]   0.00-10.08  sec  7.62 MBytes  6.35 Mbits/sec              sender
[  8]   0.00-10.08  sec  7.62 MBytes  6.35 Mbits/sec              receiver
[ 10]   0.00-10.08  sec  7.62 MBytes  6.35 Mbits/sec              sender
[ 10]   0.00-10.08  sec  7.62 MBytes  6.35 Mbits/sec              receiver
[ 12]   0.00-10.08  sec  7.62 MBytes  6.35 Mbits/sec              sender
[ 12]   0.00-10.08  sec  7.55 MBytes  6.28 Mbits/sec              receiver
[ 14]   0.00-10.08  sec  7.62 MBytes  6.35 Mbits/sec              sender
[ 14]   0.00-10.08  sec  7.51 MBytes  6.25 Mbits/sec              receiver
[ 16]   0.00-10.08  sec  7.62 MBytes  6.35 Mbits/sec              sender
[ 16]   0.00-10.08  sec  7.61 MBytes  6.33 Mbits/sec              receiver
[SUM]   0.00-10.08  sec  53.4 MBytes  44.4 Mbits/sec              sender
[SUM]   0.00-10.08  sec  53.2 MBytes  44.2 Mbits/sec              receiver

iperf Done.

there's a little room left for improvement, if any at all. mt76 driver development stalled and if you need better performance switch to your original mediatek drivers that are not officialy supported by LEDE/OpenWrt projects.

The test clearly show lot of room for improvement. Unfortunately you are right, development stalled. But the test show on the TX side (as seen from the chip-side) there needs to be an improvement.

Again, I can't do it, so no complaints that any developer didn't manage yet, just showing some figures why (that) people on this chipset are having slow performance.

For me it makes it more clear where any bugs in the code should be solved or code optimized.

As for my support from Lede, I understand. I'm just looking for an intermediate solution to improve my wifi speeds. Besides it's a learning experience for me too...took 2 more days just to get it to compile again between kernel 4.4 and 4.9.

Hi @drbrains. Development speed of the mt76 has picked up recently and I tried to repeat your tests with the latest updated open mt76 drivers and lede snapshot on my mt7621 platform (Single core dual thread (880mhz MIPS). Tested using mt7612e driver from WLAN laptop (iperf3 default client mode-sending) to Wired Computer (iperf3 server default mode receiving) and get around 40 Mbits/sec. The router CPU appears to be maxed and only using 1 thread.

mt76x2

Same test WLAN laptop (iperf3 default client mode-sending) to Wired Computer (iperf3 server default mode receiving) but this time using the mt7603e driver. Router CPU is not stretched and task is reasonably spread between 2 cpu threads.
mt7603.

I was wondering if you had also seen the router CPU bound issues with the mt7612e driver. If so we could file a mt76 github issue for the developers?

I never tried using HTOP to see the different loads per core, I installed it just to see what that would give me as additional information. I can confirm that I'm getting the same 40Mbps on average on the MT7612e. The MT7603, which is suppose to be slower, I can get above 100Mbps on a good run, but I would say it averages more around 85Mbps, which is still good considering I'm only using it as HT20 in an apartment building with a lot of other wifi on the 2.4Ghz band.

I'm compiling the latest MT76 driver now with the last commits from yesterday. Let's see if that make a difference. Interestingly enough I could get MT7621 - MT7628 on the MT7612e driver around 100Mbps per second on my efforts to get 802.11s Mesh working. (Thats iperf3 on both routers).

try to get MT7662E1_BBP_CR_20130116.xls

I’m not sure what that would help. Enlighten me on the more inner workings of this device and/or driver. I noticed there is a reference to this file in the MTK GPL source code but it doesn’t seem to be included.

In all cases that might improve the original driver, how would that benefit the open source MT76??

no idea. ask @nbd about that.

i'm adding this chip to rt2x00 driver bbp regs to power on chip..

[    5.215038] Loading modules backported from Linux version wt-2017-11-01-0-gfe248fc2c180
[    5.218688] Backport generated by backports.git v4.14-rc2-1-31-g86cf0e5d
[    5.225137] nf_conntrack version 0.5.0 (2048 buckets, 8192 max)
[    5.253583] xt_time: kernel timezone is -0000
[    5.271262] ip_tables: (C) 2000-2006 Netfilter Core Team
[    5.295062] PPP generic driver version 2.4.2
[    5.298229] NET: Registered protocol family 24
[    5.317413] l2tp_ppp: PPPoL2TP kernel driver, V2.0
[    5.327927] rt2800pci 0000:01:00.0: loaded eeprom from mtd device "factory"
[    5.331081] ieee80211 phy0: rt2800_load_rom_patch: Info - REV_RT76XXE1/E2
[    5.334518] ieee80211 phy0: rt2800_load_rom_patch: Info - ROM patch build: 20141115060606a
[    5.374738] ieee80211 phy0: rt2800pci_load_firmware: Info - Firmware Version: 0.0.00
[    5.378264] ieee80211 phy0: rt2800pci_load_firmware: Info - Build: 1
[    5.381142] ieee80211 phy0: rt2800pci_load_firmware: Info - Build Time: 201507311614____
[    5.390822] ieee80211 phy0: rt2800pci_load_firmware: Info - Firmware running!
[    5.394064] ieee80211 phy0: rt2x00_set_rt: Info - RT chipset 7662, rev 3000 detected
[    5.397579] ieee80211 phy0: rt2x00_set_rf: Info - RF chipset 7612 detected
[    5.408640] rt2800_wmac 10180000.wmac: loaded eeprom from mtd device "factory"
[    5.411913] ieee80211 phy1: rt2x00_set_rt: Info - RT chipset 6352, rev 0500 detected
[    5.415433] ieee80211 phy1: rt2x00_set_rf: Info - RF chipset 7620 detected
[    5.428188] usbcore: registered new interface driver rt2800usb
[    5.471828] usbcore: registered new interface driver ath9k_htc
[    5.474921] kmodloader: done loading kernel modules from /etc/modules.d/*
[   10.888133] 8021q: adding VLAN 0 to HW filter on device eth0
[   10.904834] device eth0 entered promiscuous mode
[   10.907355] br-lan: port 1(eth0.1) entered blocking state
[   10.909838] br-lan: port 1(eth0.1) entered disabled state
[   10.912459] device eth0.1 entered promiscuous mode
[   10.949056] br-lan: port 1(eth0.1) entered blocking state
[   10.951504] br-lan: port 1(eth0.1) entered forwarding state
[   14.857891] ieee80211 phy0: rt2x00lib_request_firmware: Info - Loading firmware file 'mt7662.bin'
[   14.872663] ieee80211 phy0: rt2x00lib_request_firmware: Info - Firmware detected - version: 255.0
[   14.916811] ieee80211 phy0: rt2800_wait_bbp_ready: Error - BBP register access failed, aborting
[   14.920751] ieee80211 phy0: rt2800pci_set_device_state: Error - Device failed to enter state 4 (-5)
[   15.353362] br-lan: port 2(wlan1) entered blocking state
[   15.355808] br-lan: port 2(wlan1) entered disabled state
[   15.358382] device wlan1 entered promiscuous mode
[   15.402220] br-lan: port 2(wlan1) entered blocking state
[   15.404653] br-lan: port 2(wlan1) entered forwarding state
[   22.658746] jffs2_scan_eraseblock(): End of filesystem marker found at 0x0
[   22.661868] jffs2_build_filesystem(): unlocking the mtd device... [   22.664617] done.
[   22.665485] jffs2_build_filesystem(): erasing all blocks after the end marker... [   42.150705] done.
[   42.151599] jffs2: notice: (1301) jffs2_build_xattr_subsystem: complete building xattr subsystem, 0 of xdatum (0 unchecked, 0 orphan) and 0 of xref (0 dead, 0 orphan) found.
[   43.947375] random: crng init done

@drbrains I performed some more iPerf3 testing with the latest build from laptops to a wired server using 5Ghz mt7612e radio. Laptop clients were 3 meters away and within line of sight from my WNDR3700v5 box. In the table I've included the WNDR3700v5 CPU usage which which seems to scale normally nor is the processor overloaded. The mt7612e driver seems to work really good in this build.
OpenWrt SNAPSHOT r5638-0f72690

mode width Mhz client Rx -R Mbits/sec client Tx Mbits/sec mt76 CPU% Rx mt76 CPU% Tx mt76 Rx MCS mt76 Tx MCS
802.11ac 40 250 140 75% 52% 9 9
802.11n 20 115 121 41% 53% 15 15
802.11n 20 115 94 45% 45% 14 15
802.11n 40 215 115 65% 55% 14 15