Monit not restarting stalled programs - how to troubleshoot?

I have Monit running on my CentOS 5.2 VPS. Due to probably lack of RAM (and probably some memory hogs in my VPS range) some programs stall sometimes.

Management software is Webmin/Virtualmin.

So far Monit restarted them. However, since a short while Monit will no restart Postfix and Dovecot. Monit itself sometimes stalls too, but when I restart it my understanding is that will autostart other apps that are down - and it doesn't.

How can I troubleshoot that?

/etc/monit.d/monitrc :

Code:

set daemon  60
set logfile syslog facility log_daemon
set mailserver localhost
set mail-format { from: abuse@****.com }
set alert admin@**********.com
#set httpd port 2812 and
#     SSL ENABLE
#     PEMFILE  /var/certs/monit.pem
#     allow admin:test

check process postfix with pidfile /var/spool/postfix/pid/master.pid
   group mail
   start program = "/etc/init.d/postfix start"
   stop  program = "/etc/init.d/postfix stop"
   if failed port 25 protocol smtp then restart
   if 5 restarts within 5 cycles then timeout

check process dovecot with pidfile /var/run/dovecot/master.pid
   group mail
   start program = "/etc/init.d/dovecot start"
   stop  program = "/etc/init.d/dovecot stop"
   if failed port 25 protocol smtp then restart
   if 5 restarts within 5 cycles then timeout

check process usermin with pidfile /var/usermin/miniserv.pid
   start program = "/etc/init.d/usermin start"
   stop  program = "/etc/init.d/usermin stop"
   group misc
   if failed host 127.0.0.1 port 20000 type tcp then restart
   depends usermin_init
	
check file usermin_init with path /etc/init.d/usermin
group misc

check process webmin with pidfile /var/webmin/miniserv.pid
start program = "/etc/init.d/webmin start"
stop  program = "/etc/init.d/webmin stop"
group misc
if failed host 127.0.0.1 port 10000 type tcp then restart
depends webmin_init
	
check file webmin_init with path /etc/init.d/usermin
group misc

 

Which virtualization technique do you use? Do you have access to the host system?