Passenger and Apache Memory Munin Plugin

passenger_memory_stats.rb

#!/usr/bin/ruby
# Passenger and Apache Memory Munin Plugin

# put in /usr/share/munin/plugins/ and link into /etc/munin/plugins then restart munin-node
# by Dan Manges, http://www.dcmanges.com/blog/rails-application-visualization-with-munin
# small changes by jfqd 2010-03-25
# NOTE: you might need to add munin to allow passwordless sudo for passenger-memory-stats

def output_config
  puts <<-END
graph_category App
graph_title Passenger and Apache Memory
graph_vlabel MB
apache.label apache
passenger.label passenger
END
  exit 0
end

def output_values
  apache = nil
  passenger = nil

  `/usr/bin/passenger-memory-stats`.each_line do |line|
    next unless /### Total private dirty RSS: (\d+\.\d+) MB/.match(line)
    passenger = $~[1] unless apache.nil?
    apache ||= $~[1]
  end

  puts "apache.value #{apache}"
  puts "passenger.value #{passenger}"
end

if ARGV[0] == "config"
  output_config                                                
else
  output_values
end