presto-spi/src/main/java/io/prestosql/spi/Page.java/Page/updateRetainedSize
class Page:    private void updateRetainedSize()
    {
        long retainedSizeInBytes = INSTANCE_SIZE + sizeOf(blocks);
        for (Block block : blocks) {
            retainedSizeInBytes += block.getRetainedSizeInBytes();
        }
        this.retainedSizeInBytes.set(retainedSizeInBytes);
    }