fork-it.rb

require 'logger'
require 'mongo_mapper'

MongoMapper.database = 'tmp'

class Foo
  include MongoMapper::Document
  key :id, Integer
end

Foo.collection.remove

forks = 4
a = 0
b = 650000 # 649976

forks.times do |i| 
  Kernel.fork do
    log = Logger.new("/Users/#{`whoami`.strip}/tmp/log-#{i}.log")
    count = (b-a) / forks
    # puts "#{count * i} - #{count * i + count}"
    c = ((count * i)..(count * i + count))
    c.each do |n|
      log.info n
      Foo.create(:name => n)
    end
  end
end

Process.waitall