Speedtest causes 100% IRQ Download only

General questions
1

Hello everyone,

I’m running a fully virtualised environment with 1 XenServer VM behind 1 VyOS gateway.
All this is running on Epyc 64c/512G RAM/25Gb Net brand new hypervisor.

Curious behaviour : when running a speedtest on the VM, the IRQ CPU goes to 100% on the VyOS router ONLY during the download phase, the upload does not cause any IRQ.

VyOS VM has 2 vCPUs + 2 GB mem.

Where does this come from? I can’t explain the up/down difference.

Thanks,

Gaëtan

2

Which VyOS version are you using? How are you connected to the internet, PPPoE? Is NAT used?

3

Hello,

Version : 1.4-rolling
NAT : no
Internet : default route to edge routers.

Thanks

4

Hello @gallart , I hope this is possible to explain with perf top from linux-tools
package repositories/current/pool/main/l • dev.packages.vyos.net

Could you try to clear nft ruleset and compare the difference?

sudo nft flush ruleset
5

Flushing nft ruleset has no impact.

Here is the perf top :

Screenshot 2021-04-19 213356
Screenshot 2021-04-19 2133561143×453 13.2 KB

6

Hello @gallart , on which hypervisor running VyOS. Could you provide and output

show interfaces ethernet eth0 physical
7

It’s running on top of XCP-NG.

Settings for eth0:
Link detected: yes
driver: vif
version: 5.10.25-amd64-vyos
firmware-version: 
expansion-rom-version: 
bus-info: vif-0
supports-statistics: yes
supports-test: no
supports-eeprom-access: no
supports-register-dump: no
supports-priv-flags: no

And public interfaces :

vyos@rc-vm4-01:~$ show interfaces ethernet eth1 physical
Settings for eth1:
    Link detected: yes
driver: vif
version: 5.10.25-amd64-vyos
firmware-version: 
expansion-rom-version: 
bus-info: vif-1
supports-statistics: yes
supports-test: no
supports-eeprom-access: no
supports-register-dump: no
supports-priv-flags: no
vyos@rc-vm4-01:~$ show interfaces ethernet eth2 physical
Settings for eth2:
    Link detected: yes
driver: vif
version: 5.10.25-amd64-vyos
firmware-version: 
expansion-rom-version: 
bus-info: vif-2
supports-statistics: yes
supports-test: no
supports-eeprom-access: no
supports-register-dump:
8

Do you have any chance to run Debian 10 and test performance? It looks like something with a virtual network driver.

9

You mean setting-up a Debian VM on our XCP-NG pool and check for network performance?

10

Yes, exactly. Try please