processes-and-pubsub.rb

require 'httparty'
require 'redis'
require 'json'
require 'timeout'

$publisher  = Redis.new
$subscriber = Redis.new

CHANNEL = 'omg'

URLS  = %w(https://google.com http://yahoo.com https://www.mobilecommons.com)

start = Time.now
pids = URLS.map do |url|
  fork do
    result = HTTParty.get(url)
    sleep 3 # pretend the result was hard to get

    data = result.headers.to_a.to_json

    $publisher.publish CHANNEL, data.to_json
  end
end

results = []

begin
  Timeout.timeout(5) do
    $subscriber.subscribe(CHANNEL) do |on|
      on.message do |channel, msg|
        data = JSON.load(JSON.load(msg)) # hack

        results << data
      end
    end
  end
rescue
  done = Time.now - start
  puts "Done in #{done}"
  puts results.inspect
end

threads.rb

require 'httparty'

URLS = %w(https://google.com http://yahoo.com https://www.mobilecommons.com)

results = []

start = Time.now
URLS.map do |url|
  Thread.new(results) do |results|
    results << HTTParty.get(url).response
    sleep 3
  end
end.each &:join
done = Time.now - start

puts results.inspect
puts "Done in #{done}"