private static NodeResources getFreeCapacityTotal(NodeList nodes) {
        return nodes.hosts().state(State.active).asList().stream()
                    .map(n -> freeCapacityOf(nodes, n))
                    .map(NodeResources::justNumbers)
                    .reduce(new NodeResources(0, 0, 0, 0, any).justNumbers(), NodeResources::add);
    }
A version 6.163.20 will be returned as a number 163.020. The major
version can normally be inferred. As long as the micro version stays
below 1000 these numbers sort like Version.
node-repository/src/main/java/com/yahoo/vespa/hosted/provision/maintenance/MetricsReporter.java