Why use TDB and LMDB?

[Jeremy Allison]

On Wed, May 20, 2020 at 09:46:02PM +0300, hezekiah maina via samba-technical wrote:
> Hi everyone,
> 
> I'm still learning Samba and one of the question I haven't figured out yet
> is why
> Samba uses TDB or LMDB instead of RDBMS like Postgres or MySQL?

RDBMS like Postgres or MySQL are more heavyweight than tdb and
lmdb. i.e. we think they'll be slower. A lot slower.