There are a few things that slow down email:
in /etc/xinetd.d/smtp_psa - disable reverse dns lookups when sending mail:
server_args = -Rt0 ...
Take a close look at the server_args line.. is it referencing a defunct RBL?
Make sure there isn't a mail box corruption issue (Restore settings f
You need to identify why the box is running with a load average of 3 (3.00 or
more?). For a single CPU box, 3.00 is pretty high. I found a crude thumbrule
(very crude) is a box starts slowing down when load is 0.7 * (number of CPU's).
I try to keep all single CPU servers under 1.00.
Use
I have an old plesk system where it continually has many "messages in
queue but not yet preprocessed" and the messages in queue gets more and
more behind. It accpets mails, but doesn't handle them quickly.
It doesn't have any noticable bottlenecks.
It appears to start doing this when ever the l