Transactional
LMDB provides full ACID semantics with MVCC, reader/writer transactions, and deadlock-free serialized writes.
Embedded Database
LMDB: Lightning Memory-Mapped Database
An ultra-fast, ultra-compact, crash-proof, key-value embedded data store developed by Symas for the OpenLDAP Project.
Symas LMDB
Small, Fast, Persistent
Symas LMDB is an extraordinarily fast, memory-efficient database developed for the OpenLDAP Project. With memory-mapped files, LMDB delivers the read performance of a pure in-memory database while retaining the persistence of standard disk-based databases.
LMDB is only about 32KB of object code, but it is the right 32KB: compact, efficient, and powerful.
Concurrent
Readers do not block writers, writers do not block readers, and multiple processes can open the same environment on the same host.
Memory-Mapped
LMDB uses memory-mapped files for zero-copy lookup and iteration while fully exploiting the operating system’s buffer cache.
Maintenance-Free
LMDB requires no external process, background cleanup, compaction, application-level cache, logs, or crash recovery procedure.
Ordered Map Interface
Keys are always sorted, making range lookups straightforward and efficient.
Multiple Sub-Databases
LMDB supports multiple sub-databases, with transactions covering all sub-databases in the environment.
Where to Get It
LMDB Source Code
Development occurs in the OpenLDAP Project git repository on the
mdb.master branch. A clone of the LMDB code is also available
on GitHub.
Technical Information
Symas LMDB Tech Info
Symas LMDB has been written about, talked about, and utilized in a variety of impressive products and publications. We invite you to learn more on our dedicated Technical Information page.
Support & Services
Symas LMDB Support
Symas offers fixed-price Gold or Enterprise source-level support for organizations using LMDB in their applications.
LMDB Support
Get source-level support from the team connected to LMDB’s development history and OpenLDAP integration.
View Support Plans →Community
Search discussions on the OpenLDAP mailing lists for LMDB community conversations, technical details, and development history.
OpenLDAP Mailing Lists →Porting & Professional Services
Thinking about switching your application to LMDB? Symas can provide developer support or porting services to help with the transition.
Contact Symas →