presto-spi/src/main/java/io/prestosql/spi/block/ByteArrayBlockBuilder.java/ByteArrayBlockBuilder/getPositionsSizeInBytes
class ByteArrayBlockBuilder:    @Override
    public long getPositionsSizeInBytes(boolean[] positions)
    {
        return (Byte.BYTES + Byte.BYTES) * (long) countUsedPositions(positions);
    }