Flint 2 - slow LAN1

Technical Support for Routers
1

Hi all,

My negotiated speed is showing as 2.5 Gbe (LAN1); however, when performing a speed test or running iperf3, the speeds are always under a gigabit.

My setup:

  • Flint 2 (4.7.0)
  • 3 Gbit fiber connected to WAN (speed test on the router maxes out the port at around 2.4 Gb, as expected)
  • LAN1 is connected to my MacBook Pro using a USB-C to 2.5 Gbe adapter (negotiated speed on both router/MacBook is showing as 2500 Mbps full duplex). I tried two other USB to 2.5 Gbe adapters using Mac/Windows, but saw no difference (I also tried various Cat6 cables).

iperf3 -c 192.168.1.1
Connecting to host 192.168.1.1, port 5201
[ 5] local 192.168.1.137 port 52232 connected to 192.168.1.1 port 5201
[ ID] Interval Transfer Bitrate
[ 5] 0.00-1.00 sec 70.9 MBytes 594 Mbits/sec
[ 5] 1.00-2.00 sec 64.8 MBytes 543 Mbits/sec
[ 5] 2.00-3.00 sec 61.4 MBytes 515 Mbits/sec
[ 5] 3.00-4.00 sec 60.8 MBytes 510 Mbits/sec
[ 5] 4.00-5.00 sec 64.0 MBytes 537 Mbits/sec
[ 5] 5.00-6.00 sec 59.4 MBytes 498 Mbits/sec
[ 5] 6.00-7.00 sec 58.8 MBytes 493 Mbits/sec
[ 5] 7.00-8.00 sec 70.4 MBytes 590 Mbits/sec
[ 5] 8.00-9.00 sec 63.5 MBytes 533 Mbits/sec
[ 5] 9.00-10.00 sec 61.1 MBytes 513 Mbits/sec

[ ID] Interval Transfer Bitrate
[ 5] 0.00-10.00 sec 635 MBytes 533 Mbits/sec sender
[ 5] 0.00-10.00 sec 634 MBytes 532 Mbits/sec receiver

Is there something or a setting that I am missing here?

Thanks

2

If you have the router connected to the computer perhaps It could be something about the router or about the adapter. But, as I see, It seems something software, yes. Have you enabled Full Cone NAT on the Flint?

3

There’s a problem with LAN1 performance. Look for a potential improvement on upstream OpenWRT forum main MT6000 thread. Also running iperf3 directly on it produces lower results than when using for example 2 laptops.

1 Like
4

Hi, I just tried with Full Cone NAT enabled, but it makes no difference:

iperf3 -c 192.168.8.1
Connecting to host 192.168.8.1, port 5201
[ 5] local 192.168.8.211 port 62032 connected to 192.168.8.1 port 5201
[ ID] Interval Transfer Bitrate
[ 5] 0.00-1.00 sec 64.6 MBytes 540 Mbits/sec
[ 5] 1.00-2.00 sec 59.2 MBytes 497 Mbits/sec
[ 5] 2.00-3.00 sec 57.4 MBytes 481 Mbits/sec
[ 5] 3.00-4.00 sec 55.9 MBytes 469 Mbits/sec
[ 5] 4.00-5.00 sec 54.9 MBytes 460 Mbits/sec
[ 5] 5.00-6.00 sec 59.0 MBytes 495 Mbits/sec
[ 5] 6.00-7.00 sec 54.2 MBytes 455 Mbits/sec
[ 5] 7.00-8.00 sec 54.8 MBytes 459 Mbits/sec
[ 5] 8.00-9.00 sec 60.5 MBytes 507 Mbits/sec
[ 5] 9.00-10.00 sec 59.1 MBytes 496 Mbits/sec

[ ID] Interval Transfer Bitrate
[ 5] 0.00-10.00 sec 580 MBytes 486 Mbits/sec sender
[ 5] 0.00-10.00 sec 579 MBytes 485 Mbits/sec receiver

I'm not even asking for full 2.5g, but the above is pretty poor..

1 Like
5

I'll check it out, thx. I also tried a snapshot build, which seems worse, since with that build I can no longer attain the maximum speeds my provider offers.

1 Like
6

Did you try with software and hardware offloading enabled?

For improved LAN1 you need the script that fixes CPU affinity.

2 Likes
7

Tried with software/hardware offloading enabled but no difference. Can you share the script, please? Thanks!

1 Like
8

The CPU affinity script is only for Flint 2? Could work too in other devices (Marble)?

9

LAN1 improvements:

taskset -p -c 0,2,3 `pgrep mtk_eth-5`
taskset -p -c 0,1,2 `pgrep mtk_eth-6`
2 Likes
10

It could work for other devices as well. You need to check what kernel threads are hogging the CPU during iperf3 runs. Run htop with "hide kernel threads" disabled in settings to see what’s happening

1 Like
11

Thanks!!

12

Thank you! I'll give it a shot once I get home and report.

I also contacted support and referenced this thread (a few hours back). Hopefully they can assist as well! :slight_smile:

1 Like