Understanding LMDB Database File Sizes and Memory Utilization

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:


Symas Corporation recently merged with Joshua Tree Software, developers of the Fortress Role-Based Access Control (RBAC) Open Source Software suite. Fortress is based on OpenLDAP and has been shown to work well with Apache Directory Server (ApacheDS) as well. Fortress is the only production-ready implementation of the ANSI INCITS 359-2004 RBAC Standard available today.