[lelouch11]

The same argument came up in a big company, incidentally for the same use case, certificate store in a CA. This led to benchmarks, where OpenLDAP was significantly slower, like three orders of magnitudes. Databases have gotten really faster in the last couple of years while OpenLDAP has stagnated.

[hyc_symas]

InnoDB is a bloated pig. No, it hasn't gotten 5 orders of magnitude faster in the past 10 years. http://www.lmdb.tech/bench/memcache/

And the overhead of SQL processing vs LDAP protocol hasn't improved any either.

You're spouting lies.

[hyc_symas]

Got a link to a report on that?

OpenLDAP serves queries at line rate on multi-gigabit NICs, with latencies indistinguishable from ping RTTs. Other databases aren't even close.