Nagios Passenger memory check

gistfile1.rb

#!/usr/local/bin/ruby

require 'rubygems'
gem 'passenger'
require 'phusion_passenger'
require 'phusion_passenger/platform_info'
require 'phusion_passenger/admin_tools/memory_stats'
require 'optparse'

include PhusionPassenger

def pluralize(str, count)
  if count > 1 
    "#{str}s"
  else
    str
  end
end

def singularize(str, count)
  if count > 1
    str
  else
    "#{str}s"
  end
end

options = {:warning_threshold => 80, :critical_threshold => 100}
OptionParser.new do |opts|
  opts.banner = "Usage: check_passenger [options]"
  opts.on("-w N", "--warning", "Warning threshold in MB") do |w|
    options[:warning_threshold] = w.to_i
  end
  opts.on("-c N", "--critical", "Critical threshold in MB") do |c|
    options[:critical_threshold] = c.to_i
  end
end.parse!

procs = AdminTools::MemoryStats.new.passenger_processes

msg, exit_code = if procs.find { |p| p.rss > options[:critical_threshold]*1000 }
  count = procs.count {|p|p.rss > options[:critical_threshold]*1000 }
  ["CRITICAL - #{count} #{pluralize('instance', count)} #{singularize('exceed', count)} #{options[:critical_threshold]} MB", 2]
elsif procs.find {|p| p.rss > options[:warning_threshold]*1000 }
  count = procs.count {|p|p.rss > options[:warning_threshold]*1000 }
  ["WARNING - #{count} #{pluralize('instance', count)} #{singularize('exceed', count)} #{options[:warning_threshold]} MB", 1]
else
  ["OK - No processes exceed #{options[:warning_threshold]} MB", 0]
end

puts "PASSENGER #{msg}"
exit exit_code