private void maybeSetDuperModelAsComplete() {
        if (superModelIsComplete && infraApplicationsIsComplete) {
            duperModel.setComplete();
        }
    }
Within the region, trying to accesss the duper model (without already having the lock)
will cause an IllegalStateException to be thrown.
service-monitor/src/main/java/com/yahoo/vespa/service/duper/DuperModelManager.java