Archer C7 v4 vs v5 - performance experiences?

Hardware Questions and Recommendations
1

My setup: Cable modem, provides 250 Mbps down. This is was connected to a C2300 providing routing/firewall/AP and VVAN trunking to an Archer C7 v4 acting as a dump AP. I was getting 250+ Mbps from both units on 5 GHz with 80MHz channel. However the C2300's 5 GHz radio intermittently stopped every few days, forcing a reboot. I replaced it with a C7 v5, with the same configuration but I can only seem to get 130-140 Mbps, and I am at a loss to know why.

The v5 looks a bit cost-cut: only one USB, non-detatchable antennas, but the same hardware is reported (Qualcomm Atheros QCA956X ver 1 rev 0) but surely they can't have cheaped out so much to make a difference like this.

When connected to both v4 and v5, openwrt reports link speed of 866 Mbps, VHT-MCS 8 / VHT-NSS 2

All OpenWrt: 23.05.3

I suppose the obvious test would be to swap v4/v5 duties and see what happens but that would take some time. Any ideas of what could explain this?

Thanks

2

You can try flipping ath10k kmod and firmware to -ct or vice versa, keeping board data.
I have V2 and V5 and they both do ~400Mbps NAT wired 300 wireless non-ct, wifi on both is crashing every now and then with default -ct

3

v4 and v5 are virtually identical, at least from the technical point of view in all relevant aspects. I assume that the different rooms in your home (with their individual EM characteristics, ranging from walls/ ceilings to neighbouring APs) have more of an impact on your findings, than the difference between v4 and v5 (although there's always the possibility that one of your devices is defective). Cross-checking is always sensible in cases like this (but be sure to test both devices individually in the respective other location).

4

Thanks for your feedback on the similarity of the models. I don't think it's environmental: I am 4m line-of-sight away in both cases, and the C2300 which had high throughput was in the same position as the v7.

5

You need to examine ligs around "radio stopped", if that is dfs trigger you may need to change initial channel

6

Thanks for your reply - unfortunately I am not familiar with what you mean by "-ct" - is this an alternative driver or something?

7

Oh hold on! I found the "Software flow offloading" under the Firewall -> General Settings. I had neglected to copy this over from the C2300 config.

I turned it on, and immediately my download throughout jumped to 260 - 270 Mbps !!

So that explains the difference.

1 Like
8

I don't really know how that works though. I had eliminated routing/firewall as a factor because when using the v4 - packets have to be routed via the v5's firewall anyhow through a wired interface. So whatever it is doing, it must be specifically related to moving packets via a wireless interface.

I guess I will take the win and move on.

9

Ahh, I forgot to mention that :slight_smile:
Absolute must once you figure bandwidth is limited by CPU usage.

10

Yes, it is 2 driver+firmware sets - one from mainline kernel, other from candelatech. Dont bother if you do not experience mystery radio restarts (not radar, not high load or anything logical-looking)