CPU not using Turbo/burst

Installing and Using OpenWrt
1

I installed the x86 version on a Zotac mini pc with Intel N4100 cpu.
When i installed Wireguard, I only got ~200Mbps on my connection using Speedtest.net that gives +800Mps with no vpn. This is about the same as my Nvidia Shield with vpn.

I installed htop and noticed my cpu only operates between 800-1000Mhz which is the base cpu min/max and does not go near its 2Ghz max.
According to htop, cpu is hitting +70% during speedtest, which I would think is enough to bump the cpu over 1Ghz?

I tried enabling/disabling ACPI in the bios with no change so I think the issue is OpenWRT.

Any suggestions/tps are appreciated.

2

Turbo works only with one core (2 hyperthreads if applicable) active.
You have 4 cores - 70% is on one core or each core?

3

I believe only one core hit 70.

I assume to get higher Wireguard speeds, the cpu's need to scale up more and if so, how?

Thanks for your reply

4

Can you show that picture of htop ( in settings un-hide kernel threads and show cpu detail)?
likely enable irqbalance.

5

Does this show you what you need to see?

Screenshot from 2024-12-20 20-39-29
Screenshot from 2024-12-20 20-39-291366×768 142 KB

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6

Go with irqbalance, cpu usage is from wireguard.

7

Sorry, I'm not familiar with getting around htop. How do I get to irqbalance?

8

OK, looks like you are telling me to install a package.
Ill give it a try.

Just to clarify the cpu usage shown, I took that during a speedtest to show the cpu stuck well below the 2Ghz max.

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9

I installed irqbalance and do not see any difference in the speed test.

Any suggestion for getting the cpu;s to scale above 1GHz?
i really think that is the cause of the slow Wireguard speed

Thanks

10

OK, I booted up a live usb of Rescuezilla which is based on Ubuntu.
Installed htop and I could see the cpu's scaling up to 2.4Ghz.

So it seems to be an issue with OpenWRT, not my bios settings etc.

Any help getting the cpu scaling to work appreciated.

11

If I run lscpu, I get

CPU max MHz: 2400.0000
CPU min MHz: 800.0000

So for some reason, the system wont scale above the base 1.1Ghz, even though it seems to know the max is 2.4Ghz.

Any insights appreciated

12

For anyone having a similar issue.
This probably isnt the correct way but I seem to have solved it by adding the below lines to /etc/rc.local

echo ondemand > /sys/devices/system/cpu/cpufreq/policy0/scaling_governor
echo ondemand > /sys/devices/system/cpu/cpufreq/policy1/scaling_governor
echo ondemand > /sys/devices/system/cpu/cpufreq/policy2/scaling_governor
echo ondemand > /sys/devices/system/cpu/cpufreq/policy3/scaling_governor

This seems to have set the governor to ondemand

13

Server can shut off cores in bios to have better base frequency in bios.

14

Try schedutil

15

Thats is what the system was using originally but for some reason would only scale between 800-1.1GHz.
I should actuallly try setting it back with the above lines to see if that works.

16

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