Archer C7 and LAN performance

I have TP-Link Archer C7 v2 with OpenWrt 19.07 and recently I have changed my internet speed from 250Mbit to 500Mbit. Unfortunately internet speed on my PC have not changed so I have checked on the same cable direct connection to modem and then I have full speed of 500Mbit. Is this something I can fix? I don’t know it is connected with Openwrt or hardware but theoretically it is gigabit router so what can be wrong?

You could run iperf3 on the router as server and test with the PC as client to check your LAN connectiviy.
Also check the CPU load with htop on the router.

# opkg update && opkg install iperf3 htop

Start the server.
# iperf3 -s -V -D

Start htop to monitor CPU load when you speedtest your Internet or your LAN:
# htop

Start htop as client on the PC
iperf3.exe -c [IP address of your router]

These are the results from my PC with a Linksys WRT1200AC.

iperf3.exe -c 192.168.90.254
Connecting to host 192.168.90.254, port 5201
[  4] local 192.168.90.220 port 53523 connected to 192.168.90.254 port 5201
[ ID] Interval           Transfer     Bandwidth
[  4]   0.00-1.00   sec   112 MBytes   936 Mbits/sec
[  4]   1.00-2.00   sec   111 MBytes   933 Mbits/sec
[  4]   2.00-3.00   sec   112 MBytes   933 Mbits/sec
[  4]   3.00-4.00   sec   111 MBytes   936 Mbits/sec
[  4]   4.00-5.00   sec   111 MBytes   935 Mbits/sec
[  4]   5.00-6.00   sec   111 MBytes   934 Mbits/sec
[  4]   6.00-7.00   sec   111 MBytes   929 Mbits/sec
[  4]   7.00-8.00   sec   111 MBytes   935 Mbits/sec
[  4]   8.00-9.00   sec   111 MBytes   935 Mbits/sec
[  4]   9.00-10.00  sec   111 MBytes   929 Mbits/sec
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval           Transfer     Bandwidth
[  4]   0.00-10.00  sec  1.09 GBytes   933 Mbits/sec                  sender
[  4]   0.00-10.00  sec  1.09 GBytes   933 Mbits/sec                  receiver

The Archer C7 is a 720 MHz mips 74Kc single core CPU, 500 MBit/s are probably well beyond its abilities (I don't even think it can fully cope with 250 MBit/s). While you can try to improve your situation by enabling software flow-offloading, it's effectively time to look for a (much) faster router.

Any recomendations for new router that will have good OpenWrt support Wi-Fi 6, real 1000Mbit and will not make me bankrupt :wink: ?

I fear that will have to be x86_64 at this point.

mvebu can route at 1 GBit/s line speed, but its wireless situation is hopeless.
mt7621 can only do it with tricks (hardware flow-offloading), but the SOC is rather slow (so if you want vpn/ sqm or anything beyond mere routing, that would be kind of a problem).
ipq807x is very promising, but not quite supported yet (in progress, but not finished).

I was reading about https://www.amazon.com/Netgear-R7800-100NAS-Nighthawk-Ethernet-Compatible/dp/B0192911RA?th=1 but I think I would like something newer. what do you think about new series https://www.amazon.com/NETGEAR-Nighthawk-12-Stream-Router-Rax200/dp/B01MQDZXA4?tag=p00935-20&ascsubtag=01JmGcjhYW8TtMNQExuEsSZ&th=1?

Broadcom is actually capable of 1gbps wan, after fixes.see more details here OpenWRT 19.07 and bcm53xx target + flow offloading

As you can see - very poor ;(

Connecting to host 192.168.0.1, port 5201
[ 4] local 192.168.0.159 port 55748 connected to 192.168.0.1 port 5201
[ ID] Interval Transfer Bandwidth
[ 4] 0.00-1.01 sec 34.0 MBytes 282 Mbits/sec
[ 4] 1.01-2.00 sec 33.9 MBytes 286 Mbits/sec
[ 4] 2.00-3.00 sec 34.6 MBytes 290 Mbits/sec
[ 4] 3.00-4.00 sec 33.4 MBytes 281 Mbits/sec
[ 4] 4.00-5.00 sec 33.9 MBytes 283 Mbits/sec
[ 4] 5.00-6.00 sec 26.9 MBytes 226 Mbits/sec
[ 4] 6.00-7.00 sec 35.4 MBytes 296 Mbits/sec
[ 4] 7.00-8.00 sec 34.4 MBytes 289 Mbits/sec
[ 4] 8.00-9.00 sec 34.6 MBytes 291 Mbits/sec
[ 4] 9.00-10.01 sec 34.0 MBytes 283 Mbits/sec


[ ID] Interval Transfer Bandwidth
[ 4] 0.00-10.01 sec 335 MBytes 281 Mbits/sec sender
[ 4] 0.00-10.01 sec 335 MBytes 281 Mbits/sec receiver

@a_guy I'm not sure how can I turn off GRO in OpenWrt. Is this simple or I have to do some complicated stuff?

ethtool -K eth0 gro off

takes effect immediately and has to be run on startup

500 MBit/s are probably well beyond its abilities

It can actually cope, just without SQM. In the firewall settings, enable software flow offloading, and that's it. No need to buy a new router.

1 Like

"enable software flow offloading" is working for me.
I have 300 Mbps provider speed. When "software flow offloading" is disabled my speed is download: 305.13Mbps / upload: 212.30Mbps. After enabling I have download:329.70 / upload:328.74
Additionally with enabled "software flow offloading" CPU load not exceed 60% load. With disabled options CPU load is 100%. Thanks!

The tradeoff is increased buffer bloat.