Netgear R7800 exploration (IPQ8065, QCA9984)

fantom-x · 2019-12-23T00:44:08.302Z

shelterx:

Btw, like wired pointed out, IRQ 28 & 29 doesn't exist, so that particular tweak won't work at all.
It's IRQ 45 and 46 for wifi on this router, for some reason you can't set smp affinity on those. Might be a driver issue (?), you can only change affinity on GIC IRQs and ath10k_pci is using PCI-MSI IRQs.

It all still works in 19.07

shelterx · 2019-12-23T07:32:13.418Z

What does? Setting the affinity for wifi? 4.19.88 below.

$ uname -a
Linux nighthawk 4.19.88 #0 SMP Fri Dec 20 09:10:22 2019 armv7l GNU/Linux
$ cat /proc/interrupts
---snip---
 45:   37202094          0   PCI-MSI 524288 Edge      ath10k_pci
 46:   15512040          0   PCI-MSI 134742016 Edge      ath10k_pci
---snip---

$ echo 2 > /proc/irq/45/smp_affinity
ash: write error: Invalid argument

fantom-x · 2019-12-23T12:21:48.537Z

As I said , it all works in 19.07 which is 4.14.

shelterx · 2019-12-23T15:55:51.557Z

Odd... wonder what's changed then, that seems like a minor flaw in 4.19 unless it's done for a reason.

MV_wrt · 2019-12-23T18:18:48.176Z

@locojohn @perceival @RainGater

Can you guys please confirm that in order to get that performance improvement for 4.14 you put this in the local startup:
for FILE in /sys/class/net/*; do echo 3 > $FILE"/queues/rx-0/rps_cpus"; echo 3 > $FILE"/queues/tx-0/xps_cpus"; done

for 4.19 this:
for FILE in /sys/class/net/*; do [ -f "$FILE/queues/rx-0/rps_cpus" ] && echo 3 > $FILE"/queues/rx-0/rps_cpus"; [ -f "$FILE/queues/tx-0/xps_cpus" ] && echo 3 > $FILE"/queues/tx-0/xps_cpus"; done

thank you

perceival · 2019-12-23T18:21:28.220Z

See that post: Build for Netgear R7800
It's universal and is going to work with both kernels.

Ansuel · 2019-12-25T16:48:13.180Z

The L2 fix and new cpufreq driver are approved and waiting to be merged

katzenjammer · 2019-12-25T23:19:31.676Z

wired:

Where do these IRQ 28 and 29 come from? I don't see them if I cat /proc/interrupts

Seems to be wrong, I also do not see them on K4.19 master builds. Instead, wifi seems to be on 45 and 46, as mentioned in posts below. But changing assignment for 45 and 46 is not allowed for some reason. Do not know why 28 and 29 were in Kong builds (I only recently started using CLI and learning/checking about what does what, before it was just copy in forum, paste in Luci, so I do not have more info).

odrt:

Which performance specifically do you want to improve?

If you already get line speed routing through your setup, you are satisfied with the measured latency and the CPU has idle cycles left on your application full load, then there is nothing to gain maybe just except for having fun playing with parameters.

If you e.g. want to get big improvements on VPN encryption performance you probably need x86 based devices.

These parameter tweaks are more small optimizations.

For me this is currently mostly playing and exploring, as, it seems, R7800 is more or less able to handle my not-so-fast line speed even with SQM cake on. However, I have not yet compared if irqbalance maybe gave some noticeable improvements. Lately the router throughput seems better to me, but this may as well be just some improvements gained from moving to master branch (?). I will compare throughly one day (this or next week) and then give feedback. So far though seems that I might have to agree, that these are actually only small tweaks and improvements and do not actually change much.

shelterx:

Yes... thanks, also the script for uhttpd is missing ` signs in the grep line.

What would you say, does it make sense to keep these in rc.local? I'm wondering if there really is any measureable improvement from just setting lower priority for two processes?

fantom-x · 2019-12-25T23:54:19.973Z

katzenjammer:

if there really is any measureable improvement from just setting lower priority for two processes?

Those processes are competing for CPU with dnsmasq, stubby, hostapd, and the likes so it does make sense to lower their priorities.

hnyman · 2019-12-26T09:53:54.035Z

Ansuel:

L2 fix and new cpufreq driver are approved and waiting to be merged

They have been merged today.

fantom-x · 2019-12-26T09:58:49.567Z

Does not look like all of the commits from your PR have been merged: is there a reason for that? Just curious.

Ansuel · 2019-12-26T10:29:33.844Z

? what commit has not being merged ?

shelterx · 2019-12-26T11:02:06.328Z

katzenjammer:

What would you say, does it make sense to keep these in rc.local? I'm wondering if there really is any measureable improvement from just setting lower priority for two processes?

Don't think it matter much... but if you really want all the oomph out of the router there's no reason to remove it.
Here are the corrected scripts:

# There is no need for collectd to run above nice == 19
if ! `grep "NICEPRIO=19" /etc/init.d/collectd`; then
   sed -i 's/^NICEPRIO.*/NICEPRIO=19/g' /etc/init.d/collectd
   # Restart does not pick up the above change right away
   (sleep 300 ; /etc/init.d/collectd stop; sleep 15; /etc/init.d/collectd start) &
fi

# There is no need for uhttpd to run above nice == 19
if ! `grep "nice -n 19" /etc/init.d/uhttpd`; then
   sed -i "s/procd_set_param command/procd_set_param command nice -n 19/g" /etc/init.d/uhttpd
   # Restart does not pick up the above change right away
   (sleep 300 ; /etc/init.d/uhttpd stop; sleep 15; /etc/init.d/uhttpd start) &
fi

Also here are the correct IRQ tweaks for 4.19 (since setting IRQs for wifi doesn't work when I write this).

# bind eth0 and eth1 to different cpu cores for even distribution, IRQ31 - WAN, IRQ32 - LAN
echo 2 > /proc/irq/31/smp_affinity
echo 1 > /proc/irq/32/smp_affinity

# set adm dma to use cpu core 2, 
echo 2 > /proc/irq/30/smp_affinity

And for future reference, here are the settings for wifi:

# CURRENTLY DOES NOT WORK NEEDS GIC-0 IRQ mode to work!  IRQ45 - 5Ghz, IRQ46 - 2.6Ghz
#echo 1 > /proc/irq/45/smp_affinity
#echo 2 > /proc/irq/46/smp_affinity

fantom-x · 2019-12-26T11:21:26.650Z

Ansuel:

? what commit has not being merged ?

Nvm, I am seeing things...

johnnysl · 2019-12-26T11:54:31.487Z

@ansuel: are you planning to work on more things soon that I can test? Or is it better to switch back to master now?

Ansuel · 2019-12-26T12:06:37.826Z

I'm now away from the router... Will put more work on half January... So yes you can switch back to master
Next step will be ad fab scaling and l2 volt scaling

johnnysl · 2019-12-26T12:21:58.028Z

Ok, thanks and enjoy the holidays

wired · 2019-12-27T18:53:00.346Z

FWIW, I had a random reboot with 4.19, running hnyman's build r11734-b085e0586f-20191220. Any way to make the logs persistent? Though when it reboots it may not even get a chance to log anything.

ACwifidude · 2019-12-27T19:15:44.583Z

Ansuel:

I'm now away from the router... Will put more work on half January... So yes you can switch back to master
Next step will be ad fab scaling and l2 volt scaling

Thanks for the good work. Excited for the upcoming changes!

shelterx · 2019-12-28T10:21:20.616Z

wired:

Any way to make the logs persistent?

You could login to the router and run logread -f in a terminal like putty until the router crashes.

Or mount a usb drive or stick and point the log to it, it also seems to support remote logging.
See here:

OpenWrt Wiki – 5 Feb 11

Logging messages

Logging messages This article relies on the following: * Accessing web interface / command-line interface * Managing configs / packages / services / logs Introduction The OpenWrt system logging facility is an important debugging/monitoring...