Server Has Sudden Increase in CPU Usage and Load

[jspp]

Hello,

I'm experiencing a strange CPU usage/load issue:
After starting (/restarting) my server, it has a CPU usage and load, which I would consider normal (CPU usage is around 6% and load around 1).
Then after a few days (6 or so), all of a sudden the CPU usage and load increase to about 40-50% CPU usage and a load of about 5-6. When looking at top/htop I see that the kvm process has a high CPU usage. When looking at the VMs in Proxmox I can see that their CPU usage went up from 2-3% to 15-20%. However when SSH-ing into the VMs the CPU usage is as I would expect at 2-3%.
I can also feel the impact of this as SSH connections and so on take longer.
Looking through journalctl I can't find anything suspicous. The only "fix" I have for the problem is restarting the server, which brings the CPU usage and load back to normal, until they eventually go up again the same way.

My server configuration is the following:
CPU: 12 x AMD Ryzen 5 3600 6-Core Processor (1 Socket)
RAM: 32GB ECC
Mainboard: ASRock X470D4U
Storage:
- for Proxmox and VM root volumes: 2x500GB SSD in a ZFS mirror
- for data storage: 2x8TB HDD in a ZFS mirror

I'm running a few VMs on my server, which all don't do heavy work, except for the router VM (OPNsense), which does a bit of work.

Additionally I have the following info:
- At some point I switched the CPU from a Ryzen 3 3200G to the Ryzen 5 3600 (because I realized that the Ryzen 3 3200G doesn't support ECC) and I'm not sure if I had the issue with the 3200G.
- I update my Proxmox regularly and I think a few months ago, there was a period, where I didn't experience this issue. (I'm using the no-subscription repos, since this is a server I use at home).

Best regards,
Julian

 

[MiamiJack]

I'm not as familiar with proxmox, but have run postfix servers under centos for several years.
My initial question would be are you seeing a lot of messages being processed at the time you are seeing high CPU?
Do you have a lot of regular expressions or domains listed in your allow / block?
Are there attachments on messages that are going through at the time you are getting the load? ( maybe you could send yourself a medium sized xls or doc ).
Do you see a lot of useless connections to postfix from random IP's that aren't really doing anything?

These are the things I would tend to see cause spikes, analyzing files for viruses, content etc too many block or allow domains and such if each is a regular expression a little more work for the processor and then getting 10 or more at a time doing all of the above.

 

[jspp]

I'm not as familiar with proxmox, but have run postfix servers under centos for several years.
My initial question would be are you seeing a lot of messages being processed at the time you are seeing high CPU?
Do you have a lot of regular expressions or domains listed in your allow / block?
Are there attachments on messages that are going through at the time you are getting the load? ( maybe you could send yourself a medium sized xls or doc ).
Do you see a lot of useless connections to postfix from random IP's that aren't really doing anything?

These are the things I would tend to see cause spikes, analyzing files for viruses, content etc too many block or allow domains and such if each is a regular expression a little more work for the processor and then getting 10 or more at a time doing all of the above.

I'm sorry, if it wasn't clear from my initial posting, but I'm not running a mail server. I'm running Proxmox Virtual Environment with a few VMs on it (neither of which do mail).

 

[MiamiJack]

My appologies! I must have clicked on the wrong forum side
I would help here as well, but I'm on the vmware side...
Good luck!

 

[jspp]

My appologies! I must have clicked on the wrong forum side
I would help here as well, but I'm on the vmware side...
Good luck!

Thank you!