Hi,
yesterday I migrated and old version with sendmail + courier to a virtual machine (vmware) with postfix and dovecot 2.0.9.
Everything worked fine, but with a more or less default setup for both dovecot and postfix, lmtp performance was pretty bad: a message was written to an inbox every 2 or 3 seconds. With that rate and a 5000+ and growing mail queue mail delivery was really slow.
After searching both the wiki and this list I didn't find anything related to this. I tried a couple of things, and finally added
process_min_avail = 10
to service lmtp entry in 10-master.conf and
local_destination_concurrency_limit = 10
in postfix's main.cf
Now mail delivery is really fast, and my mail queue was delivered in a very sort time. Is this the right solution, or there's a better setup to improve mail delivery performance?
Also, if this is a common problem, may be something should appear in http://wiki2.dovecot.org/LMTP
Thanks.
Joseba Torre. Vicegerencia de TICs, área de Explotación