The
default_process_limit configuration parameter gives direct
control over how many daemon processes Postfix will run. As of
Postfix 2.0 the default limit is 100 smtp client processes, 100
smtp server processes, and so on. This may overwhelm systems with
little memory, as well as networks with low bandwidth.
You can change the global process limit by specifying a
non-default
default_process_limit in the main.cf file. For example,
to run up to 10 smtp client processes, 10 smtp server processes,
and so on:
/etc/postfix/main.cf:
default_process_limit = 10
You need to execute "postfix reload" to make the change effective.
The limits are enforced by the Postfix
master(8) daemon which does
not automatically read main.cf when it changes.
You can override the process limit for specific Postfix daemons
by editing the master.cf file. For example, if you do not wish to
receive 100 SMTP messages at the same time, but do not want to
change the process limits for local mail deliveries, you could
specify:
/etc/postfix/master.cf:
# ====================================================================
# service type private unpriv chroot wakeup maxproc command + args
# (yes) (yes) (yes) (never) (100)
# ====================================================================
. . .
smtp inet n - - - 10 smtpd
. . .
