My typical monit + Upstart combination.

foobar.monit.conf

check process foobar with pidfile /var/run/foobar.pid

  start program = "/sbin/start foobar"
  stop program = "/sbin/stop foobar"
  
  if mem usage > 2%
    for 2 cycles
    then restart

  if failed host 127.0.0.1 port 8000 protocol HTTP
    request /
    timeout 20 second
    then restart

  if 2 restarts within 30 cycles then alert

foobar.upstart.conf

description "foobar"

start on filesystem or runlevel [2345]
stop on runlevel [!2345]

respawn
respawn limit 10 5

# hack to create a pid file for monit, for mem and pid checks
post-start script
  echo `status foobar | sed 's/.*process //'` > /var/run/foobar.pid
end script

exec /var/apps/foobar/current/bin/foobar