I would like to post a video that I presented this month regarding LMDB troubleshooting. I made this presentation using the Meet the Experts framework from SAP.
In this video I showed some points that must be checked in case of issues with LMDB, where to look, what are the most important transactions, how to check and ensure the consistency of SLD and LMDB. The link with this video is available below.
Mateus de Freitas Pedroso