public int getNumSearchPartitions() {
        if (numSearchPartitions >= 0) return numSearchPartitions;
        return uniquelyInherited(RankProfile::getNumSearchPartitions, n -> n >= 0, "num-search-partitions").orElse(-1);
    }
Returns a read only map view of the rank properties to use in this profile. This is never null.
config-model/src/main/java/com/yahoo/schema/RankProfile.java