db

An embedded LSM-tree based key-value storage engine implemented in C++, inspired by LevelDB.

Roadmap

Architecture

Write → WAL → MemTable (SkipList)
                 ↓ flush
           SSTable (Level 0..6)
                 ↓ compaction
             SSTable (Level 1..6)
Read → MemTable → Immutable MemTable → SSTable (levels)

Build

make build

Test

make test

Benchmark

The db_bench target is a TalusDB port of LevelDB's database benchmark. If LevelDB is checked out at ../leveldb, the following command builds both Release binaries and runs the same sequential-write, random-write, sequential-read, and random-read workload against LevelDB first and TalusDB second:

make benchmark

Override BENCHMARK_ARGS, LEVELDB_DIR, LEVELDB_BUILD_DIR, LEVELDB_BENCHMARK_DB, or TALUSDB_BENCHMARK_DB on the make command line when needed. Write benchmarks recreate their separate database directories. Use paths on the same real filesystem instead of /tmp when measuring storage performance.

Directory Structure

include/      Public headers
src/
  db/         MemTable, SkipList, InternalKey
  table/      Block, SSTable, TableBuilder, Filter, Iterator
  util/       Comparator, Coding, CRC32C, Arena, Env, Bloom
tests/        Unit tests
benchmarks/   Performance benchmarks