RBR50 performance is very poor - Interrupt bound?

Installing and Using OpenWrt
1

I am trying to get the build for the Netgear orbi RBR50 to work, it installed fine and configured wifi and internet easily.
However throughput from LAN to WAN seems really slow. On a 800Mbps fibre connection it is maxing out at around 130Mbps over both the wired ethernet LAN port and the 5GHz wifi.

From the output of top it looks like it may be interrupt bound and unable to handle the data rate

PID PPID USER STAT VSZ %VSZ %CPU COMMAND
10 2 root RW 0 0% 18% [ksoftirqd/0]

Any suggestions to make this work properly?

2

See if irqbalance gives you any improvement. Either way, you won't hit your WAN speeds since the OEM firmware has proprietary offload functionality OpenWrt doesn't have access to.

3

Unfortunately irqbalance makes zero difference, throughput is 1/4 the speed of my internet connection and therefore openwrt is not viable on Netgear orbi's

4

Let's add a qualifier to that: not viable for higher speed internet plans. If you wanna route 800 Mbps on OpenWrt, you'll need to look into beefier hardware unfortunately. Blame vendors for using proprietary accelerators instead of collaborating on a framework everyone can use.

5

I know it's unfortunate the drivers are behind NDA's for the system on chip.
The performance with the rbr50 maxes out at around 120 to 150mbps with openwrt which is an entry level internet connection these days.

1 Like
6

That really depends on where you live I guess, but yes. I would expect IPQ4019 to attain higher speeds though, it's a rather recent ARM SoC after all. Are you using SQM?

7

I'm not sure, it's pretty much all default settings, haven't changed anything but what's necessary to make WiFi and the internet work. The bandwidth is limited on wired ethernet too though so not a WiFi issue

8

Enable software flow offloading and you will get a substantial boost, not 800mbit but still more than 140.

And most of the entire planet would be over the moon to have access to even 140. Fastest internet available in my part of Australia is 70mb, and that’s shared medium wireless!

9

Ok, good advice, so "enable packet steering across all CPUs" got me to 220mbps, and "software offloading" improved that to 240Mbps.

10

And yes I suppose we are lucky to have fibre to the home since 2010 which is now gigabit capable. Some parts of the UK have good internet, others really struggle with slow speeds over copper wires