bitset.rb

require 'hiredis'
require "redis/connection/hiredis"
require 'redis'

$redis = Redis.new(:host => "127.0.0.1", :port => 6379)

unless $redis.exists 'SanDiego'
  puts "Creating 35 million entries"
  start = Time.now
  idx = 0
  3_500.times do |n|
    $redis.pipelined do 
      10_000.times {|m| $redis.setbit('SanDiego', idx, rand(2)); idx += 1}
    end
  end
  finish = Time.now
  puts "took #{finish - start} to create 35M entries"
end

100.times do
  user_id = rand(35_000_000)
  subscribed = $redis.getbit('SanDiego', user_id) == 1
  puts "User #{user_id} is #{subscribed ? 'subscribed' : 'not yet subscribed'}"
end