hollow/src/main/java/com/netflix/hollow/core/memory/FreeOrdinalTracker.java
public void returnOrdinalToPool(int ordinal) {
        if(size == freeOrdinals.length) {
            freeOrdinals = Arrays.copyOf(freeOrdinals, freeOrdinals.length * 3 / 2);
        }

        freeOrdinals[size] = ordinal;
        size++;
    }
public void returnOrdinalToPool(int ordinal) {
        if(size == freeOrdinals.length) {
            freeOrdinals = Arrays.copyOf(freeOrdinals, freeOrdinals.length * 3 / 2);
        }

        freeOrdinals[size] = ordinal;
        size++;
    }
Return an ordinal to the pool after the object to which it was assigned is discarded.

@param ordinal the ordinal