@olivierlambert So it turns out this issue wasn't caused by open-vm-tools.

Even after uninstalling it from all our hosts in XCP, we still had several hosts climb to 100% CPU shortly after a migration.

While combing through sar logs and several crash dumps, I found that the system load would rapidly increase in a short amount of time until the host was unreachable.

I gathered from the crash dumps that the high load appeared to be caused by threads in spinlocks waiting on storage.

This led me to believe the older kernel (4.18) was having difficulty recovering from the migration process.

The simple fix was to upgrade the OS to Rocky 9 on some hosts and upgrade the kernel on ones not ready to have the OS upgraded.

We've been running for a couple weeks without an issue.

@jshiells I was wrong, open-vm-tools is installed on a lot of the systems we migrated. I just assumed it wasn't instead of checking. We'll remove it from all the systems, test further, and report back. Thank you for the insight!

@olivierlambert That was my initial thought, PV driver in the older kernel. No process is using very much CPU in the guest though the total CPU is at 100% (when running top in the VM).

Haven't been able to get Rocky 9 to fail yet, but it can take a day or two.