There's no information about ps:restore in docs: https://dokku.com/docs/processes/process-management/
Provide information about available options and clarify how restore is running during server reboot.
Is it serial, parallel?
Does it use all available CPU's?

Relevant slack thread: https://gliderlabs.slack.com/archives/C0FP0R13J/p1638463734039600
Relevant issue about ps:restore: #4967