presto-array/src/main/java/io/prestosql/array/DoubleBigArray.java/DoubleBigArray/allocateNewSegment
class DoubleBigArray:    private void allocateNewSegment()
    {
        double[] newSegment = new double[SEGMENT_SIZE];
        if (initialValue != 0.0) {
            Arrays.fill(newSegment, initialValue);
        }
        array[segments] = newSegment;
        capacity += SEGMENT_SIZE;
        segments++;
    }