Journals or Logs are the metadata that describes a data system’s history of state.

    Journals are key to RocksDB’ integrity and recovery. RocksDB has two types of journals: Write Ahead Log (WAL) for journaling the in-memory state updates, and MANIFEST for journaling the on-disk state updates. RocksDB’s transaction module also relies on journaling, especially WAL, for transaction commit, recovery, and abort.

    More details in: