There are lot of articles for NameNode heap calculation, but none on DataNode.
1. How to calculate the DataNode heap size?
2. How to calculate the object size of each Object in the DataNode Heap?
3. What does the Metadata of the DataNode heap contains? It cannot be similar to NameNode (as it does not have replication details etc. ), also, it should have metadata for checksum stored etc, so how does metadata of DataNode looks like. How is it different from NameNode Metadata?