The Lightning Memory-mapped Database (LMDB) is designed around the virtual memory facilities found in modern operating systems, Multi-version Concurrency Control (MVCC), and Single-Level Store (SLS) concepts. This design is quite different than those of more traditional databases and, in operation, it can mimic behaviors that system administrators have been trained to recognize as signs of trouble. With LMDB, though, the behaviors are normal, but nonetheless this leads to the following questions:
Yes, LMDB is fast, blindingly fast. Can we make it faster still? Yes.
Early last year our client Acision ran a torture test on Symas OpenLDAP as part of acceptance testing for their telco offerings. These tests were performed on a directory consisting of one master replicating to two consumers, and included a number of crash/recovery tests as well as performance measurements. The short summary of the results: after two weeks of continuous testing, no problems.
Getting Down and Dirty with LMDB: Q&A with Symas Corporation’s Howard Chu About Symas’s Lightning Memory-Mapped Database
Howard Chu, the Chief Architect for the OpenLDAP Project and CTO of Symas Corporation, discusses Symas’s Lightning Memory-Mapped Database (LMDB), the memory-mapped database that was developed and contributed to the OpenLDAP Project by Symas. In this interview we discuss the nitty gritty of the database and why it’s “not just another new database”.