Celluloid & DCell

Transcript

1. Celluloid DCell &

2. @vanstee github.com/vanstee Patrick Van Stee highgroove.com

3. @tarcieri Revactor Reia nio4r Cryptosphere cool.io

4. brew install zeromq gem install dcell Setup

5. Celluloid General purpose concurrency framework for Ruby built on the

   Actor Model

6. class Counter attr_reader :count def initialize @count = 0 end

   def increment @count += 1 end end

7. class Counter attr_reader :count def initialize @count = 0 @mutex

   = Mutex.new end def increment @mutex.synchronize do @count += 1 end end end

8. Threads are hard!

9. class Counter include Celluloid attr_reader :count def initialize @count =

   0 end def increment @count += 1 end end

10. Actor Model

11. •No shared state •Communicate with messages •Process messages sequentially

12. class Counter include Celluloid def increment(count, actor) return count if

    count < 10000 actor.increment( count + 1, Actor.current ) end end

13. & Asynchronous Method Calls Futures

14. counter = Counter.new # returns immediately counter.increment! puts counter.count #

    returns immediately future = counter.future :increment puts future.value

15. module Enumerable def map(&block) futures = map do |item| Celluloid::Future.new(

    item, &block ) end futures.map(&:value) end end

16. Caveats

17. • The GIL in MRI does not allow parallelism •

    Threads and Fibers are expensive • Concurrency is still a hard problem [not really]

18. DCell

19. Celluloid General purpose concurrency framework for Ruby built on the

    Actor Model DCell Distributed Celluloid over 0MQ

20. “I thought of objects being like biological cells or individual

    computers on a network, only able to communicate with messages. Alan Kay

21. • Exposes Actors on the Network • Send messages as

    you normally would

22. DRb DCell Threads Actors

23. Demo

24. Also Checkout Sidekiq

25. github.com celluloid/celluloid celluloid/dcell

26. Hack Night