LevelDB

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LevelDB
Jeffrey Dean, Sanjay Ghemawat, Google Inc.
Stable release
1.23[1] Edit this on Wikidata
/ 23 February 2021; 3 years ago (23 February 2021)
Repository
Written in
New BSD License
Websitegithub.com/google/leveldb Edit this on Wikidata

LevelDB is an

New BSD License and has been ported to a variety of Unix-based systems, macOS, Windows, and Android.[5]

Features

LevelDB stores keys and values in arbitrary byte arrays, and data is sorted by key. It supports batching writes, forward and backward iteration, and compression of the data via Google's Snappy compression library.

LevelDB is not an

indexes
. Applications use LevelDB as a library, as it does not provide a server or command-line interface.

MariaDB 10.0 comes with a storage engine which allows users to query LevelDB tables from MariaDB.[6]

History

LevelDB is based on concepts from Google's

IndexedDB implementation. They wrote LevelDB starting in early 2011, with the same general design as the Bigtable tablet stack, but not sharing any of the code.[7]

Usage

LevelDB is used as the backend database for

blockchain metadata using a LevelDB database.[9] Minecraft Bedrock Edition uses a modified version for chunk and entity data storage.[10]
Autodesk AutoCAD 2016 also uses LevelDB.

Performance

Google has provided benchmarks comparing LevelDB's performance to

Kyoto Cabinet in different scenarios.[11] LevelDB outperforms both SQLite and Kyoto Cabinet in write operations and sequential-order read operations. LevelDB also excels at batch writes, but is slower than SQLite when dealing with large values. The currently published benchmarks were updated after SQLite configuration mistakes were noted in an earlier version of the results.[12] Updated benchmarks[13] show that LevelDB also outperforms Berkeley DB, but these tests also show that OpenLDAP LightningDB
is much faster (~10 times in some scenarios) in read operations and some write types (e.g. batch and synchronous writes, see the link above), and is almost equal in the rest of the test.

All the above benchmarks date back from 2011 to 2014, and may only be of historical significance as SQLite, for instance, became significantly more efficient.[14]

Bugs and reliability

LevelDB has a history of database corruption bugs.[15][16][17][18][19][20] A study from 2014 has found that, on non-checksummed file systems, the database could become corrupted after a crash or power failure.[21]

See also

References

  1. ^ "Release 1.23". 23 February 2021. Retrieved 13 March 2021.
  2. ^ "Google Research Scientists and Engineers: Jeffrey Dean". Google, Inc.
  3. ^ "Research Scientists and Engineers: Sanjay Ghemawat". Google, Inc.
  4. ReadWriteWeb. July 30, 2011. Archived from the original
    on August 16, 2011. Retrieved July 30, 2011.
  5. ^ "Google Open Source Blog: LevelDB: A Fast Persistent Key-Value Store". Google, Inc.
  6. ^ LevelDB storage engine
  7. ^ Jeff Dean. "LevelDB mailing list: "Current Status of LevelDB"".
  8. ^ LevelDB. Docs.basho.com. Retrieved on 2013-09-18.
  9. ^ Andreas M. Antonopoulos. "Chapter 7. The Blockchain". Retrieved 8 January 2015.
  10. ^ "Bedrock Edition level format". Minecraft Wiki. Retrieved 24 September 2023.
  11. ^ "LevelDB Benchmarks". Google, Inc. Archived from the original on 2011-08-20.
  12. ^ "LevelDB Benchmark discussion".
  13. ^ Database Microbenchmarks Archived 2014-08-09 at the Wayback Machine, Symas Corp., 2012-09. Retrieved 22 October 2016
  14. ^ "Measuring and Reducing CPU Usage in SQLite".
  15. ^ Repairing LevelDB
  16. ^ Issues · google/leveldb · GitHub
  17. ^ Unrecoverable corruption in Chromium
  18. ^ Corruption in syncthing
  19. ^ Corruption after power loss
  20. ^ Corruption in Ethereum
  21. ISBN 9781931971164
    .

External links
Retrieved from "https://en.wikipedia.org/w/index.php?title=LevelDB&oldid=1195165222"