Upgrading should only be necessary between nearby versions, so it doesn't seem a problem to change/break the dump format now and again. But I agree that it's significant work to set up such a dump/reload mechanism if it doesn't exist yet.
When upgrading to a version of upstart which is too sidtant, it seems reasonable still to require a reboot since this will not be the common case. Would it perhaps be better not to attempt to re-exec init at all after an upgrade of this type, and simply to wait for the next reboot, having alerted the user in some way? This is not ideal, but it seems better than breaking terminal logins until the next reboot.
Upgrading should only be necessary between nearby versions, so it doesn't seem a problem to change/break the dump format now and again. But I agree that it's significant work to set up such a dump/reload mechanism if it doesn't exist yet.
When upgrading to a version of upstart which is too sidtant, it seems reasonable still to require a reboot since this will not be the common case. Would it perhaps be better not to attempt to re-exec init at all after an upgrade of this type, and simply to wait for the next reboot, having alerted the user in some way? This is not ideal, but it seems better than breaking terminal logins until the next reboot.