This has made me leery of Oracle Cloud in the past. https://docs.oracle.com/en-us/iaas/Content/FreeTier/freetier...:
> Idle Always Free compute instances may be reclaimed by Oracle. Oracle will deem virtual machine and bare metal compute instances as idle if, during a 7-day period, the following are true:
> • CPU utilization for the 95th percentile is less than 20%
> • Network utilization is less than 20%
> • Memory utilization is less than 20% (applies to A1 shapes only)
The stupid but presumably effective solution is to waste resources to keep above those limits.
Another solution is offered by the email multiple sources cite they send when they reclaim (or warn they will reclaim? not clear) an instance:
> You can keep idle compute instances from being stopped by converting your account to Pay As You Go (PAYG). With PAYG, you will not be charged as long as your usage for all OCI resources remains within the Always Free limits.
They warn they will reclaim. I had two accounts, one processing data for a free weather service I volunteer for, so it's not idle and has had no issues for a couple of years now. The other for personal projects, so at times it stays idle for a while and I would get these email warnings which made me switched it to paid. I have not paid a cent, again for a couple of years now.