The k3s supposed to be the lightweight k8s, but it used more than 10% when no container running. The problem was reported when TrueNAS running as VM.
This issue also caused high disk utilization, which caused whole system slow, huge IO wait.
There is a zpool called ix-applications created for k3s. To stop k3s process, needs to unset pool in Apps => Settings => Unset Pool.
After Unset Pool, the CPU utilization dropped from 70% to 5%.
Note: This is follow up action of Memory test hung after upgrade to 64GB RAM
This machine was installed TrueNAS, but reboot quite often, about few times a week. After that, I changed it to Proxmox, then one of the active VM kept hanging.
I decided to re-look into the memory test issue.
If only install 32GB memory, the test was OK at beginning. But after full day of testing, start to have 1 failure in one pass, not many but not acceptable.
If install 48GB or 64GB memory, the test caused system hanging in black screen.
After reduce the memory speed to 1066 for 64GB memory, looks OK in Pass 1, but Pass 2 got issue again.
After full day of testing, the test result was getting worse. Previously hung at 80%+, then hung at 40%+. Then looks like problem caused by other factors, such as temperature, etc.
Then I noticed that the power supply is very hot and no noise. Then I think the issue could be the system was not getting enough power.
After take out the power supply, found that power supply fan was not turning. Normally, this issue can not be detected, because the fan towards the bottom of casing.
I got one new power supply, after installed new power supply, the system become colder.
After changed the power supply, the memory passed when setting at speed of 1333, which is also the speed detected by motherboard. Even the motherboard auto overclocked CPU speed to 4000+ (CPU speed should be 3600), no error too.
The new set of RAMs can pass testing at 1600 speed, but the old set got error less than 1 minute.
Although the spec of the old and new RAMs are all the same, brand, speed, etc, but the system detected the new RAMs are 1600, but old set are 1333, no matter in which memory slot. I'm not sure whether the lower speed is caused by aging or because cheated by seller.
During the testing, I noticed that the testing speeds are quite different among 1600, 1333 and 1066 if they are under same CPU speed.