public boolean equals(Object o) {
        if (o == this) {
            return true;
        }
        if (!(o instanceof ConfigKey)) {
            return false;
        }
        ConfigKey<?> key = (ConfigKey<?>) o;
        return (name.equals(key.name) &&
                configId.equals(key.configId) &&
                namespace.equals(key.namespace));
    }
Comparison sort order: namespace, name, configId.
config/src/main/java/com/yahoo/vespa/config/ConfigKey.java