Quanah Gibson-Mount:
> Hi,
>
> I see on <http://www.postfix.org/ADDRESS_VERIFICATION_README.html>, it
> recommends using a btree database for the address verify map. For example:
>
>
> # Default setting for Postfix 2.7 and later.
> # Note 1: Be sure to read the "Caching" section below!
> # Note 2: Avoid hash files here. Use btree instead.
> address_verify_map = btree:/var/lib/postfix/verify
>
> However, with the introduction of lmdb, I would assume it is at least an
> equally qualified replacement. Due to the hostile licensing changes to BDB,
> I no longer link any software to it. I'd like to confirm that LMDB is a
> suitable replacement for btree (and request a doc update if that is
> correct).
LMDB support was completed at the end of the Postfix 2.11 development
cycle. No new show-stopper problems have surfaced in the first
year of deployment. In my experience, LMDB's COW approach presents
a higher write load than Berkeley DB due to Postfix's tiny updates,
but that became a non-issue after I switched my server to SSD drives.
Both ADDRESS_VERIFY_README and POSTSCREEN_README show side-by-side
examples of shared (lmdb) and non-shared (btree) caches. The text
that you refer to is concerned with other features. It would not
make sense to pollute those examples with side-by-side examples
of Berkeley DB and LMDB or whatever, but it is no problem to add
"or lmdb" to the text "avoid hash, use btree instead".
Wietse
