Introducing JRuby

Given at Surrey Ruby Users Group in Guildford - Jan 2013
References other talks and videos throughout. Borrows benchmarks and material from the Torquebox team so apologies for the blatant plagiarism.

1. Introducing Surrey Ruby Users Group - 29th Jan 2013
4. mRuby
5. mRuby threads extendable lightweight
7. He who does not know foreign languages, knows nothing of his own - Goethe
8. • WTF? Clear up FUD • Why? Advantages of JRuby • How? Code Demo • When? Use cases
9. WTF? The Ruby Programming Language on the JVM
10. WTF? The Ruby Programming Language on the JVM tracks MRI 1.9.3+ rubyspec.org fully tested CI server
11. WTF? The Ruby Programming Language on the JVM
12. WTF? Java Virtual Machine • Java - write once, run anywhere • Split into Java API, and JVM • Handles compatibility with host OS • 256 bytecodes*, Java standard classes • Exceptions, GC, memory and threads *of which, only 10 matter
13. WTF? source: wikipedia http://en.wikipedia.org/wiki/ Java_virtual_machine
14. Why? Towards a better implementation... • Faster • More efficient • Reach
15. Why? What's wrong with MRI? • C extension API • Inefficient GC* • GIL / no real threads / poor multicore • The “80/20” interpreter * (better in 2.0 and 1.9.3-perf)
16. Why? What's wrong with processes? • Complete copy of app = more memory • More “complex” • Communication is hard • Cars v train • 100 core CPUs - what then? 100 VMs?
17. Why? What's wrong with processes? * However, they’re not all bad. See Unicorn, Linux and Passenger for examples...
18. Why? Scream if you want to go faster... Two options 1. Write your own VM eg. YARV, Rubinius 2.Use an existing VM JRuby, MagLev, IronRuby
19. Why? Scream if you want to go faster... The JVM •15 years engineering by whole teams • Free, Open Source • Fastest VM - comparable with C • Best GCs to choose from • All JVMs full parallel threaded • All platforms JRuby • started in 2001! • sponsored by RedHat • Free, Open Source • same memory model / threading as the JVM • Constantly refined for speed and efficiency
20. Why? Scream if you want to go faster... The JVM •15 years engineering by whole teams • Free, Open Source • Fastest VM - comparable with C • Best GCs to choose from • All JVMs full parallel threaded • All platforms JRuby • started in 2001! • sponsored by RedHat • Free, Open Source • same memory model / threading as the JVM • Constantly refined for speed and efficiency GoGaRuCo 2012- High Performance Ruby - Charles Nutter
21. Why? But Ruby is slow...
22. Why? But Ruby is slow... No, it’s not - but the applications are “the way you write your code is far more important than the runtime” - Charles Nutter
23. Why? But Ruby is slow... • Node - 3500 req/s single process, single thread • Latest Padrino ( 0.11.0 ) ???
24. Why? But Ruby is slow... • Node - 3500 req/s single process, single thread • Latest Padrino, ( 0.11.0 ) 3000 req/s
25. Why? Benchmarks - Rails / Spree Torquebox - 6th Oct 2011 • TorqueBox on JRuby 1.6.4 • Trinidad 1.2.3 on JRuby 1.6.4 • Passenger 3.0.9 standalone on REE and Ruby 1.9.2 • Unicorn 4.1.1 on REE and Ruby 1.9.2
26. Why? Benchmarks - Rails / Spree
27. Why? Benchmarks - Rails / Spree
28. Why? Benchmarks - Rails / Spree
29. Why? Benchmarks - Rails / Spree It’s a shame that the benchmarks are old 1.9.3-p194-perf and JRuby 1.7 .2 will be very different...
30. Why?
31. How? Interop #  This  is  the  'magical  Java  require  line'. require  'java' #  With  the  'require'  above,  we  can  now  refer  to  things  that  are  part  of   the #  standard  Java  platform  via  their  full  paths. frame  =  javax.swing.JFrame.new("Window")  #  Creating  a  Java  JFrame label  =  javax.swing.JLabel.new("Hello") #  We  can  transparently  call  Java  methods  on  Java  objects,  just  as  if  they   were  defined  in  Ruby. frame.getContentPane.add(label)    #  Invoking  the  Java  method   'getContentPane'. frame.setDefaultCloseOperation(javax.swing.JFrame::EXIT_ON_CLOSE) frame.pack frame.setVisible(true)
32. How? Interop #  This  is  the  'magical  Java  require  line'. require  'java' require  'path/to/mycode.jar' Java:  org.foo.department.Widget Ruby:  Java::OrgFooDepartment::Widget These two calls are equivalent java.lang.System.currentTimeMillis java.lang.System.current_time_millis x.getSomething                        becomes      x.something x.setSomething(newValue)    becomes      x.something  =  new_value x.isSomething                          becomes      x.something? JavaClass.new or JavaClass.new(x,y,z) generally works as expected
33. How? Interop ~ 50,000 libraries on Maven Clojure, Scala, Python, Javascript interop available too...
34. Why? Deployment
35. Why? Deployment WAR file Trinidad Torquebox
36. Why? Deployment WAR file Trinidad Torquebox good for a Java shop
37. Why? Deployment WAR file Trinidad Torquebox good for easy Rails deploys
38. Why? Deployment Torquebox
39. Why? Deployment Torquebox
40. Why? Torquebox
41. Why? Torquebox Rack TorqueBox supports Rack, including Rails 2.3.x, Rails 3.x, Sinatra, and others. Rack applications are served as first-class resources within the web container. The web container is clusterable, and web sessions may be shared between nodes without any additional configuration. JDBC High-performance tried-and-true Java Database Connectivity (JDBC) database drivers power your ActiveRecord and other database access. Daemons TorqueBox provides the framework to manage your daemon-like Ruby components. TorqueBox makes sure it starts and stops with your application. What you do in the middle is up to you. Scheduled Jobs Cron-like functionality is provided by the TorqueBox server. Job classes implemented in Ruby have full access to to your Ruby environment and are managed by a durable job scheduler. Messaging Your simple Ruby components can both produce and consume messages from clustered and distributed asynchronous messaging fabric powered by HornetQ. Asynchronous Tasks Leveraging the messaging system, TorqueBox makes it easy to execute simple tasks and methods asynchronously, allows your application to quickly return control to the user.
42. How? Torquebox - setup $ cd ~/torquebox_examples/rails_example $ torquebox rails apply /Users/someone/torquebox-2.3.0/share/rails/template.rb gemfile torquebox (2.3.0) remove config/initializers/session_store.rb initializer session_store.rb initializer active_record_backgroundable.rb rakefile torquebox.rake
43. How? Torquebox - background jobs class Post < ActiveRecord::Base attr_accessible :body, :title after_create :publish_to_social_network always_background :publish_to_social_network def publish_to_social_network puts "Publishing '#{title}' to twitter" sleep(5) puts "Post published" end end
44. How? Torquebox - built in cron --- # This is the TorqueBox configuration file. Refer to the TorqueBox # documentation at http://torquebox.org/documentation/current/ # for all configuration options. web: context: "/" jobs: post_counter: job: PostCounter cron: "*/10 * * * * ?" ~/torquebox_examples/rails_example/config/torquebox.yml
45. How? Torquebox - daemons class PostIdeaGrabber def initialize(options) @queue = TorqueBox::Messaging::Queue.new(options['queue_name']) end def start puts "******** Starting PostIdeaGrabber ********" Thread.new do until @done @queue.publish("Random idea #{rand(100)}") sleep 2 end end end def stop @done = true end end
46. How? Torquebox - built in cron --- # This is the TorqueBox configuration file. Refer to the TorqueBox # documentation at http://torquebox.org/documentation/current/ # for all configuration options. web: context: "/" jobs: post_counter: job: PostCounter cron: "*/10 * * * * ?" services: post_idea_grabber: service: PostIdeaGrabber config: queue_name: "/queue/post_ideas" queues: /queue/post_ideas: durable: false ~/torquebox_examples/rails_example/config/torquebox.yml
47. How? Torquebox - and the rest... • Infinispan caching •Built in clustering •Distributed transactions
48. How? Torquebox - and the rest... • Check out sample app (“Poorsmatic”) • Watch “Deploy, scale and sleep at night” GoGaRuCo 2012 - Joe Kutner
49. How? Diving in $ rvm get head $ rvm install jruby $ gem install jruby-lint $ jrlint
50. How? Diving in $ rvm get head $ rvm install jruby $ gem install jruby-lint $ jrlint
51. How? Diving in replace gems with jdbc equivalents declare pool (configure postgres) “xa:false” for torquebox
52. How? Diving in export JAVA_OPTS="-Xmx1024m -XX:MaxPermSize=256m -Djruby.compile.invokedynamic=true"
53. When?
54. When? Java shop Performance sensitive Single Product Large infrastructure Complex app (torquebox) now - just run jrlint
55. PS Threads + concurrency - Celluloid, EM-Synchrony What about the Heroku effect? Economics, worse-is-better etc. Is Ruby the right choice for parallel/concurrent apps?
56. PS Thanks! @xavriley