I am also interested in this thread. I've been doing some comparison tests between MDB and BDB using openldap 2.4.35, and find that the BDB backend is consistently much faster for writes. For example, modifying 10000 DNs and changing one attribute using ldapmodify takes about 80 seconds with an MDB backend and about 18 seconds with a BDB backend. Is there any chance that MDB write performance will catch-up (or even overtake) BDB write performance?
Chris