presto-spi/src/main/java/io/prestosql/spi/Page.java/Page/getRetainedSizeInBytes
class Page:    public long getRetainedSizeInBytes()
    {
        if (retainedSizeInBytes.get() < 0) {
            updateRetainedSize();
        }
        return retainedSizeInBytes.get();
    }