{"id":23002617,"url":"https://github.com/fjall-rs/lsm-tree","last_synced_at":"2026-01-06T02:17:34.243Z","repository":{"id":217706967,"uuid":"744614276","full_name":"fjall-rs/lsm-tree","owner":"fjall-rs","description":"K.I.S.S. 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It features:\n\n- Thread-safe `BTreeMap`-like API\n- Mostly [safe](./UNSAFE.md) \u0026 100% stable Rust\n- Block-based tables with compression support \u0026 prefix truncation\n  - Optional block hash indexes in data blocks for faster point lookups [[3]](#footnotes)\n  - Per-level filter/index block pinning configuration\n- Range \u0026 prefix searching with forward and reverse iteration\n- Block caching to keep hot data in memory\n- File descriptor caching with upper bound to reduce fopen calls\n- *AMQ* filters (currently Bloom filters) to improve point lookup performance\n- Multi-versioning of KVs, enabling snapshot reads\n- Optionally partitioned block index \u0026 filters for better cache efficiency [[1]](#footnotes)\n- Size-tiered, (concurrent) Leveled and FIFO compaction \n- Multi-threaded flushing (immutable/sealed memtables)\n- Key-value separation (optional) [[2]](#footnotes)\n- Single deletion tombstones (\"weak\" deletion)\n\nKeys are limited to 65536 bytes, values are limited to 2^32 bytes.\nAs is normal with any kind of storage engine, larger keys and values have a bigger performance impact.\n\n## Sponsors\n\n\u003ca href=\"https://sqlsync.dev\"\u003e\n  \u003cpicture\u003e\n    \u003csource width=\"240\" alt=\"Orbitinghail\" media=\"(prefers-color-scheme: light)\" srcset=\"https://raw.githubusercontent.com/fjall-rs/fjall-rs.github.io/d22fcb1e6966ce08327ea3bf6cf2ea86a840b071/public/logos/orbitinghail.svg\" /\u003e\n    \u003csource width=\"240\" alt=\"Orbitinghail\" media=\"(prefers-color-scheme: dark)\" srcset=\"https://raw.githubusercontent.com/fjall-rs/fjall-rs.github.io/d22fcb1e6966ce08327ea3bf6cf2ea86a840b071/public/logos/orbitinghail_dark.svg\" /\u003e\n    \u003cimg width=\"240\" alt=\"Orbitinghail\" src=\"https://raw.githubusercontent.com/fjall-rs/fjall-rs.github.io/d22fcb1e6966ce08327ea3bf6cf2ea86a840b071/public/logos/orbitinghail_dark.svg\" /\u003e\n  \u003c/picture\u003e\n\u003c/a\u003e\n\n## Feature flags\n\n### lz4\n\nAllows using `LZ4` compression, powered by [`lz4_flex`](https://github.com/PSeitz/lz4_flex).\n\n*Disabled by default.*\n\n### bytes\n\nUses [`bytes`](https://github.com/tokio-rs/bytes) as the underlying `Slice` type.\n\n*Disabled by default.*\n\n## Run unit benchmarks\n\n```bash\ncargo bench --features lz4\n```\n\n## License\n\nAll source code is licensed under MIT OR Apache-2.0.\n\nAll contributions are to be licensed as MIT OR Apache-2.0.\n\n## Footnotes\n\n[1] https://rocksdb.org/blog/2017/05/12/partitioned-index-filter.html\n\n[2] https://github.com/facebook/rocksdb/wiki/BlobDB\n\n[3] https://rocksdb.org/blog/2018/08/23/data-block-hash-index.html\n","project_url":"https://awesome.ecosyste.ms/api/v1/projects/github.com%2Ffjall-rs%2Flsm-tree","html_url":"https://awesome.ecosyste.ms/projects/github.com%2Ffjall-rs%2Flsm-tree","lists_url":"https://awesome.ecosyste.ms/api/v1/projects/github.com%2Ffjall-rs%2Flsm-tree/lists"}