Ruby benchmarking

fib.rb

#!/usr/bin/env ruby

def slow_fib(n)
  case n
  when 0, 1
    1
  else
    slow_fib(n-1) + slow_fib(n-2)
  end
end

puts slow_fib ARGV[0].to_i
puts RUBY_RELEASE_DATE

rand.rb

#!/usr/bin/env ruby

require 'benchmark'
require 'fileutils'

tmp_file = 'hello_world.txt'
File.open(tmp_file, "w") {|f| f << "hello world\n" }

res = Benchmark.measure do
  500000.times { rand; File.read(tmp_file) }
end

puts res.format

FileUtils.rm tmp_file

# A "slow" system will report high user times:
# user	0m6.750s
# sys	0m8.650s

# A "fast" system:
# user	0m4.640s
# sys	0m11.380s

rand.sh

#!/bin/bash

n=0
until [ $n -eq 100000 ]
do
  #read -n 1 < /dev/random
  #read < text

  n=$(( $n + 1))
done

stats.rb

#!/usr/bin/env ruby

def curl(url)
  `curl -s #{url}`
end

pub_host = curl "instance-data/lapublic-hostname"
id = curl "instance-data/latest/meta-data/instance-id"
priv_host = `hostname`.strip
az = curl "instance-data/latest/meta-data/placement/availability-zone"
cpu = `cat /proc/cpuinfo |grep GHz`.split.last
puts [priv_host, id, az, cpu].join(',')