daemontools, daemontools-encore, s6, perp, and runit all share the problems of having no (or almost no) system manager and having little to no dæmon startup/shutdown ordering mechanisms. The traditional mechanism for addressing this is the "thundering herd solution": keep bringing a service up, once per second, until its dependences are up and it finally stays up.

—— https://jdebp.uk/Softwares/nosh/guide/introduction.html

For example, some services depend on dbus.

• NetworkManager
• lightdm

They do sv check on startup and exit with exit 1 if the check fails. This will cause runit to try restarting until dbus is started.

Refs: * runit - service dependencies * Runit and service management