Voxel Custom firmware build for R7800 v. 1.0.2.93SF

[HELLO_wORLD]

Have you tried to check with ethtools before and during these tests?
ethtool -S ethlan and ethtool ethlan

As I understand the design of the router, there are only two physical ports : ethwan and ethlan.
Then ethwan is bridged to brwan, and ethlan to br0.
I am not sure how Wifi connects into that, but it is bridged somewhere to br0. It seems though that it may be in its own port as you said Wifi is unaffected.

So the weak point seems to come from the switch part of the router on the LAN side.

I have no idea if it is a hardware limitation or software. In the second case, you could try to trick the system by creating VLANs and separating 100Mbps devices from 1000Mbps ones.
Or I don’t know if there is a way to separate the switch in br0 and br1 for example…

 

[sppmaster]

Should not be hardware because I've tested the same network setup with ISP's realy cheap gigabit router and that works flawlessly. I was able to have full gigabit WAN download speed while four 100Mbps devices were transferring data over LAN from the PC server.
And the R7800 doesn't have such a WAN/LAN speed drops when all devices are connected at 1Gbps. It only happens when there is at least one 100Mbps client.
I'm not able currently to do many other tests with different configurations. Because of that I've given the steps to reproduce the issue if anyone wants to help or wish to test by himself.
I'm unable to report this to Netgear support although I've opened a thread in the Netgear community.

 

[HELLO_wORLD]

Should not be hardware because I've tested the same network setup with ISP's realy cheap gigabit router and that works flawlessly. I was able to have full gigabit WAN download speed while four 100Mbps devices were transferring data over LAN from the PC server.
And the R7800 doesn't have such a WAN/LAN speed drops when all devices are connected at 1Gbps. It only happens when there is at least one 100Mbps client.
I'm not able currently to do many other tests with different configurations. Because of that I've given the steps to reproduce the issue if anyone wants to help or wish to test by himself.
I'm unable to report this to Netgear support although I've opened a thread in the Netgear community.

Maybe the R7800 (not anything in your LAN as you made evidence of that) has a hardware limitation in its design (possibly the switch part) when it is dealing with several ethernet speeds simultaneously?

 

[sppmaster]

Doesn't seem like a limitation just because sometimes the WAN down speed is ridiculous 20-30Mbps with ping above 200-300ms. At that time the LAN traffic is around 200-300Mbps over a gigabit connection.

 

[HELLO_wORLD]

Doesn't seem like a limitation just because sometimes the WAN down speed is ridiculous 20-30Mbps with ping above 200-300ms. At that time the LAN traffic is around 200-300Mbps over a gigabit connection.

That would allow to solve that.

The only negative point is it seems to happen with any firmware… Voxel and NG are similar (Voxel uses NG as a base to keep hardware acceleration and updates it for security and adds functionalities, but it is not a whole different firmware), OpenWRT is different but yet has the same problem… That is why I was fearing some kind of bottleneck in the hardware design.

Best is to experiment with VLANs first to see if it could help and if there is a way to beat this limitation with a trick.

I cannot experiment too much as my setup is in production mode (family relies on Internet and all devices are in service). Plus I only have one 100 Mbps device, a Cisco SPA112 for SIP phone; everything else is 1 Gbps or wifi.

I don't have a spare R7800 to experiment or access to an IT lab to do so.

 

[kokishin]

Should not be hardware because I've tested the same network setup with ISP's realy cheap gigabit router and that works flawlessly. I was able to have full gigabit WAN download speed while four 100Mbps devices were transferring data over LAN from the PC server.
And the R7800 doesn't have such a WAN/LAN speed drops when all devices are connected at 1Gbps. It only happens when there is at least one 100Mbps client.
I'm not able currently to do many other tests with different configurations. Because of that I've given the steps to reproduce the issue if anyone wants to help or wish to test by himself.
I'm unable to report this to Netgear support although I've opened a thread in the Netgear community.

Hi sppmaster,

I read your writeup in the other thread. Thanks for taking the time to document this issue.

I am only using one LAN port on my R7800. I have an 8 port 1 Gb LAN Switch connected to it. That switch connects two other 8 port 1Gb switches downstream. Connected to the two downstream 1Gb switches are a mix of 1Gb and 100Mb clients. Since the R7800 LAN ports never sees a 100Mb client, have I serendipitously worked around the issue?

 

[sppmaster]

I've never tried with just one port because I didn't have enough 1Gbps devices to connect to the additional switch. Maybe I'll be able to rearrange my network setup and try this too.
If you can test and run network traffic between any 1Gbps device (if you have a PC to use as a server) and at least 2-3 100Mbps devices and at the same time you run a WAN speed test on the 1Gbps device (PC), then you can see what the result will be like.
In my tests I use iperf3 because sometimes the WAN speed remains relatively high (around 100-200Mbps) but the LAN transfers are impacted and interrupted. And I see this from the results iperf3 reads every second. And if you have WAN line speed from your ISP lower than 300Mbps you may think that everything is OK.