presto-main/src/main/java/io/prestosql/operator/PageUtils.java/BlockSizeListener/accept
class BlockSizeListener:        @Override
        public void accept(Block childBlock)
        {
            long newSize = topLevelBlock.getSizeInBytes();
            if (newSize == lastSize) {
                return;
            }
            sizeInBytesConsumer.accept(newSize - lastSize);
            lastSize = newSize;
        }