public void startAfterBootstrap() {
        maintainers.add(new FileDistributionMaintainer(applicationRepository, curator, interval, fileDirectory));
        maintainers.add(new SessionsMaintainer(applicationRepository, curator, Duration.ofSeconds(30)));
        maintainers.add(new ReindexingMaintainer(applicationRepository, curator,
                                                 Duration.ofMinutes(3), convergenceChecker, Clock.systemUTC()));
        if (applicationRepository.configserverConfig().hostedVespa())
            maintainers.add(new PendingRestartsMaintainer(applicationRepository, curator, Clock.systemUTC(), Duration.ofSeconds(30)));
    }
Maintenance jobs of the config server.
Each maintenance job is a singleton instance of its implementing class, created and owned by this,
and running its own dedicated thread.

@author hmusum
configserver/src/main/java/com/yahoo/vespa/config/server/maintenance/ConfigServerMaintenance.java