dns_resolution_stress.rb

require "benchmark"
require "logger"
require "resolv"

module Script
  def self.run(process_name, resolv_kind, dns_server_ip, nameserver_to_resolv)
    file = File.open("/tmp/dns_resolution_stress.log", File::WRONLY | File::APPEND)
    logger = Logger.new(file)
    logger.level = Logger::DEBUG

    if resolv_kind == "ruby"
      dns_resolv = Resolv::DNS.new(:nameserver => [dns_server_ip])
    end

    max = 0

    while(true)
      time =
        Benchmark.realtime do
          if resolv_kind == "ruby"
            dns_resolv.getaddress(nameserver_to_resolv)
          else
            `nslookup #{nameserver_to_resolv} #{dns_server_ip}`
          end
        end

      message = "[#{Time.now.strftime("%Y%m%d%H%M%s")}] [#{process_name}] [#{(1/time).round(1)}] [#{time}]"
      message += " **************" if time > 1

      logger.debug message
    end
  end
end

if ARGV.length != 4
  puts "use $ ruby dns_resolution_stress.rb <process_name> <resolv_kind(ruby|nslookup)> <dns_server_ip> <nameserver_to_resolv>"
  puts "exa $ ruby dns_resolution_stress.rb 001 ruby 8.8.8.8 google.com"
  exit 1
end

Script.run(ARGV[0], ARGV[1], ARGV[2], ARGV[3])