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1) Ethereum needs to store lots of data whose identifier can be said to be purely random. It makes use of LevelDB, whose indexing/sorting properties are useless here since the very key is random.

The obvious questions are - why LevelDB? Why not MySQL for instance, so to drastically improve information retrieval performance. (introduce indexing based on block height etc) Let's forget the security/ concurrency aspects which I've seen brought up. The purpose of a database is to facilitate efficient data storage and retrieval. Proper software design should be able to secure access to a local MySQL instance as well.

Thus, what's the rationale?

2) How is the data laid out in the database?

marked as duplicate by Richard Horrocks, Ismael, Achala Dissanayake, Roman Frolov, Joël Feb 28 '18 at 2:07

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  • Good question. For sure I only know that geth is using LevelDB. What about other clients? Here are some infos on that topic -> ethereum.stackexchange.com/questions/824/… . Please also check the "Related"-sidebar! – ivicaa Feb 27 '18 at 14:34
  • I wonder if it's a path dependency that follows Bitcoin's implementation. Ethereum was inspired by Bitcoin, it also uses the same elliptic curve. I wonder if the initial implementation chose level db due to the same reason. – Linmao Song Feb 27 '18 at 14:39
  • Also, Parity uses RocksDb: ethereum.stackexchange.com/questions/13639/… – Linmao Song Feb 27 '18 at 14:55
  • The question would be still perfectly valid for RocksDb with which I'm very familiar. The performance improvements stem from implementation decisions/compression etc. In RocksDB we would be still querying random keys and do not benefit from sorting. I'm talking about using block numbers as keys for instance. – Vega4 Feb 27 '18 at 15:21
  • Sure the way RocksDB is implemented would aid us much more than LevelDB but still. – Vega4 Feb 27 '18 at 15:27

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