SQM not reaching 90% of the speed (R7800, 400/40mbit)

[egc]

@vicking

Looked like indeed, but strange thing is that it also looked like the CPU didn't balance the work between the two cores. Or is this normal behavior?

Did you enable irqbalance ?

As you have found out SQM on NSS is a "bit" different, but maybe you do not need it anyway, your router is now fast enough and your internet speed looks also sufficient

[vicking]

@egc

Did you enable irqbalance ?

No didn't do that. But not sure if this was enabled by default?

@egc

As you have found out SQM on NSS is a "bit" different, but maybe you do not need it anyway, your router is now fast enough and your internet speed looks also sufficient

Yeah correct! I want to give it a try but have to find out how to do it with custom configs

[egc]

@hnyman

The irqbalance package is included in the build, but like my docs say, it is initially disabled in config and the user may take it into use if he wants.

It is not enabled by default

[moeller0]

@vicking

Strange thing is. When I enable SQM my download speed drops, even with download set to zero. I checked CPU with HTOP and max usage was like 3%

Make sure to enable the detailed CPU time display and individual bars displays for each CPU, cake/sqm are single threaded (per instance) so if the cake CPU is overloaded throuput will suffer even if the other CPUs are idle. And qdisc processing is accounted as softinterrupt context so will only show up if you enable SIRQ display.

@vicking

Sorry, looked wrong. Indeed 1 core is @ 100% while running the test.. even with download set to zero it still goes to 100% on core 0. Explaining not reaching the 400mbit I think.

Mmmh, please post the output of tc -s qdisc

@vicking

Looked like indeed, but strange thing is that it also looked like the CPU didn't balance the work between the two cores. Or is this normal behavior?

Mostly yes, you need to enable receive packet steering (for all CPUs)... I am unsure whether irqbalance alone will help here, but you can try...

[moeller0]

@vicking

And after doing a speedtest and reaching the 400/40mbit connection I filled in 360000/3600 as 90% of the speed.

When I run a speedtest how I only reach a max of 160mbit download which I dont understand.
The upload is spot on with 36mbit, what I would expect.

@vicking

        option interface 'eth0.2'
        option download '360000'
        option upload '36000'
        option qdisc 'cake'
        option script 'piece_of_cake.qos'
        option linklayer 'ethernet'
        option debug_logging '0'
        option verbosity '5'
        option overhead '22'

With these settings you can expect the following maximal throughput with on-line TCP capacity tests (for MTU 1500):

IPv4:
360 * ((1500 - 20 - 20) / (1500 + 22)) = 345.3 Mbps
36 * ((1500 - 20 - 20) / (1500 + 22)) = 34.5 Mbps
IPv6:
360 * ((1500 - 40 - 20) / (1500 + 22)) = 340.6 Mbps
36 * ((1500 - 40 - 20) / (1500 + 22)) = 34.1 Mbps

So 36 Mbps in Upload direction seems to indicate something is wrong, unless you
a) measured gross throughput
b) used one of the more loose upload capacity tests that simply failed to report precise numbers

[vicking]

Thanks for all the answers. Well I don' t thinks this needs further investigation for now as I switched to the NSS build and CPU usage/bandwith looks very good.

Only thing I would like to try now is to lower the latency by trying SMQ on this build.

As i've read on the internet both builds are great so I think I can stick with the NSS one for daily usage?

Only issue (with my Iphone I have now) is with WiFi. When I unlock my phone Wifi is disconnected for a second an I see the 5G symbo and then connects again... If I let my phone screen on it won't happen. Not sure what this is...

[vicking]

@vicking

Luci SQM and normal SQM config doesn’t work. Have to use custom config.

Got it all working now and very happy with the result!
Cpu usage stays also low!

Thanks all!

Bufferbloat Test Result: A+

[brada4]

If you could share the secret sauce that allows sqm on nss? I know of br-wan for normal flowtable.

[vicking]

I followed these instructions and just enabled it in Luci. Works great!

GitHub - rickkdotnet/sqm-scripts-nss: My Smart Queue Management Scripts for OpenWRT

[brada4]

Thats your answer to accept...