@Override
    public String toString() {
        return "application status: [" +
               "currentReadShare: " + currentReadShare + ", " +
               "maxReadShare: " + maxReadShare +
               "]";
    }
Returns an estimate of the max fraction of the global traffic to this application that may possibly
be received by the deployment in this zone.
node-repository/src/main/java/com/yahoo/vespa/hosted/provision/applications/Status.java