kill_all_rails.rb

#!/usr/bin/env ruby

pids = %x[ps ax|grep rails|grep -v grep].split("\n").map{|line| line.strip.scan(/^\d+/).first.to_i} - [Process.pid]

if pids.any?
  system "kill #{pids.join(' ')}"
  puts "killed #{pids.size} rails instance(s)"
else
  puts "no rails processes found"
end