[Dovecot] LDA vs. LMTP

[Joseph Tam]

"Martin Burgraf" <martin.bg at web.de> writes:

> According to http://wiki2.dovecot.org/LDA the recommended way is to use
> LMTP, since it's supposed to have a better performance.

The performance gains comes mostly from avoiding the overhead of invoking
an executable and spawning a new process for each delivery.  If your mail
system isn't stressed, I don't think it matters much.

> On the other hand, http://wiki2.dovecot.org/LMTP says, that LMTP is a
> backgound process, while LDA is only called when needed.  I've also
> read, that LDA only uses the users privileges, which both means, that
> LDA should be better.

I don't know why you would consider a background process inferior to a
run-on-demand executable.

> I've also noticed, that LMTP adds an additional Recieved:-Header to the mail.
> Are there any other differences?

>From a past discussion on this topic, I think Timo stated that if you
use SIS (single-instance storage or de-duping), it's more efficient
using LMTP since it knows all message bodies to multiple recipients will
be identical.

Joseph Tam <jtam.home at gmail.com>