On Wed, Jul 30, 2014 at 10:06:34AM +0100, Andrew Beverley wrote:
> Incidentally, I am submitting using the sendmail command, rather than
> SMTP (against the advice of the tuning README) - how much difference is
> this likely to make?
This doubles the disk I/O cost of message delivery and serializes
submission because pickup(8) processes one message at a time.
You'll likely get an order of magnitude higher throughput with 4--10
parallel SMTP submission streams, but even a single SMTP submission
stream will likely out-perform local submission via sendmail(1) though
not by much, the real gain is in parallel submission.
--
Viktor.
