Ruby & JVM: A (JRuby) Love Story

Transcript

1. Ruby & JVM: A (Jruby) Love Story Yarden Laifenfeld @yardenlaif
2. 2 Who Am I? • Software Engineer at Rookout • Background in low level C programming in linux IOT environments • Ruby, Java, Go • C#, Python, JavaScript, C++
3. What is JRuby? 3 “ JRuby is a 100% Java implementation of the Ruby programming language. It is Ruby for the JVM. ” - the JRuby wiki
4. 4 Should you use JRuby?
5. JRuby Advantages 5 • Integration with Java libraries • Running atop the JVM ◦ Threads ◦ Long running applications
6. Why JRuby.md - Jordan Sissel, 2010 https://gist.github.com/jordansissel/978956 6 • core and stdlib ruby changes violently and without notice and without backwards compatibility. I want nothing of that. • need a cross-ruby date library that isn't part of stdlib (see previous point) and is also good. • need an easy way to use multiple cpus that is cross-ruby (threads are not it)
7. CRuby Advantages 7 • Larger community • More features
8. 8 Should you use JRuby? I don’t know, you choose.
9. Supporting JRuby in one of Rookout’s debuggers 9
10. Supporting JRuby 10 ❏ Running an app ❏ Adding a breakpoint ❏ Collecting data
11. Decision Time 11 Java or Ruby
12. Decision Time 12 Java or Ruby
13. Running an app 13 • rails server -p 8080 -e development
14. Running an app 14 rvm install jruby rvm use jruby bundle install
15. Running an app 15
16. Running an app 16 3 business days later…
17. Running an app 17 bundle config unset force_ruby_platform
18. Running an app 18 ➜ tutorial-ruby git:(master) ✗ jruby -S rails server -p 8080 -e development => Booting Puma => Rails 6.0.3.4 application starting in development => Run `rails server --help` for more startup options Puma starting in single mode... * Version 4.3.7 (jruby 9.2.9.0 - ruby 2.5.7), codename: Mysterious Traveller * Min threads: 5, max threads: 5 * Environment: development * Listening on tcp://[::1]:8080 * Listening on tcp://127.0.0.1:8080 Use Ctrl-C to stop
19. Running an app 19 ➜ tutorial-ruby git:(master) ✗ jruby -S rails server -p 8080 -e development => Booting Puma => Rails 6.0.3.4 application starting in development => Run `rails server --help` for more startup options Puma starting in single mode... * Version 4.3.7 (jruby 9.2.9.0 - ruby 2.5.7), codename: Mysterious Traveller * Min threads: 5, max threads: 5 * Environment: development * Listening on tcp://[::1]:8080 * Listening on tcp://127.0.0.1:8080 Use Ctrl-C to stop
20. Running an app 20 ➜ tutorial-ruby git:(master) ✗ jruby -S rails server -p 8080 -e development => Booting Puma => Rails 6.0.3.4 application starting in development => Run `rails server --help` for more startup options Puma starting in single mode... * Version 4.3.7 (jruby 9.2.9.0 - ruby 2.5.7), codename: Mysterious Traveller * Min threads: 5, max threads: 5 * Environment: development * Listening on tcp://[::1]:8080 * Listening on tcp://127.0.0.1:8080 Use Ctrl-C to stop
21. Supporting JRuby 21 ? Running an app ❏ Adding a breakpoint ❏ Collecting data
22. Running an app 22 • bundle add rookout • require 'rookout' ::Rookout.start
23. Running an app 23 ➜ tutorial-ruby git:(master) ✗ jruby -S rails server -p 8080 -e development
24. Running an app 24 ➜ tutorial-ruby git:(master) ✗ jruby -S rails server -p 8080 -e development [Rookout] Successfully connected to controller.
25. Running an app 25 ➜ tutorial-ruby git:(master) ✗ jruby -S rails server -p 8080 -e development [Rookout] Successfully connected to controller. => Booting Puma => Rails 6.0.6 application starting in development => Run `rails server --help` for more startup options Puma starting in single mode... * Version 4.3.12 (jruby 9.3.8.0 - ruby 2.6.8), codename: Mysterious Traveller * Min threads: 5, max threads: 5 * Environment: development * Listening on tcp://[::1]:8080 * Listening on tcp://127.0.0.1:8080 Use Ctrl-C to stop
26. Supporting JRuby 26 ✓ Running an app ❏ Adding a breakpoint ❏ Collecting data
27. TracePoints 27
28. TracePoints 28 tracepoint = Tracepoint.new(:line) do ... end
29. TracePoints 29 tracepoint = Tracepoint.new(:line) do ... end tracepoint.enable
30. TracePoints 30 tracepoint = Tracepoint.new(:line) do ... end tracepoint.enable(target: method(:m1), target_line: 14)
31. TracePoints in JRuby 31
32. Workaround 32 tracepoint.enable
33. Supporting JRuby 33 ✓ Running an app ✗ Adding a breakpoint ❏ Collecting data
34. Decision Time 34 Java or Ruby
35. Decision Time 35 Java or Ruby
36. Supporting JRuby 36 ❏ Running an app ❏ Adding a breakpoint ❏ Collecting data
37. Running an app - Java Agents 37 • -javaagent flag • premain entrypoint • Instrumentation API App JavaAgent Instrumentation API
38. Running an app 38 ➜ tutorial-ruby git:(master) ✗ jruby -J-javaagent:rook.jar -S rails server -p 8080 -e development
39. Running an app 39 ➜ tutorial-ruby git:(master) ✗ jruby -J-javaagent:rook.jar -S rails server -p 8080 -e development [Rookout] Successfully connected to controller.
40. Running an app 40 ➜ tutorial-ruby git:(master) ✗ jruby -J-javaagent:rook.jar -S rails server -p 8080 -e development [Rookout] Successfully connected to controller. => Booting Puma => Rails 6.0.6 application starting in development => Run `rails server --help` for more startup options Puma starting in single mode... * Version 4.3.12 (jruby 9.3.8.0 - ruby 2.6.8), codename: Mysterious Traveller * Min threads: 5, max threads: 5 * Environment: development * Listening on tcp://[::1]:8080 * Listening on tcp://127.0.0.1:8080 Use Ctrl-C to stop
41. Supporting JRuby 41 ✓ Running an app ❏ Adding a breakpoint ❏ Collecting data
42. Adding a breakpoint - Class Loaders 42 JVM Compiler Code Bytecode
43. Adding a breakpoint - Class Loaders 43 JVM 32 | … 33 | new Item() 34 | … Class Loader Get Item class bytecode Return Item class bytecode
44. Adding a breakpoint - Class Loaders 44 JVM 32 | … 33 | new Item() 34 | … Class Loader Get Item class bytecode Return Item class bytecode Class Transformer Return transformed Item class bytecode
45. Adding a breakpoint 45 Expectation: Works straight away! Reality: Doesn’t work at all.
53. 53 A few, spaced out invocations Many, rapid invocations Class isn’t loaded Class is loaded
54. 54 A few, spaced out invocations Many, rapid invocations Class isn’t loaded Class is loaded JIT
55. JRuby Compilation Modes 55 • Interpretation • JIT • Compilation
56. JRuby Compilation Modes 56 compile.mode=FORCE
60. Supporting JRuby 60 ✓ Running an app ✓ Adding a breakpoint ❏ Collecting data
61. Collecting data 61 class TasksController def create params.require(:task).permit(:task) task = Task.new(params[:task][:title]) $tasks_storage.push(task) redirect_back(fallback_location: 'tasks') end end
62. Collecting data 62 class TasksController def create params.require(:task).permit(:task) task = Task.new(params[:task][:title]) $tasks_storage.push(task) redirect_back(fallback_location: 'tasks') end end
63. Collecting data 63 class TasksController def create params.require(:task).permit(:task) task = Task.new(params[:task][:title]) $tasks_storage.push(task) redirect_back(fallback_location: 'tasks') end end
64. Collecting data 64
65. Collecting data - self 65
66. Collecting data - locals 66
67. Supporting JRuby 67 ✓ Running an app ✓ Adding a breakpoint ✓ Collecting data
68. What Next? 68 • Ruby TracePoint API • Java Agents • Class Loaders @yardenlaif
69. Thank You! @yardenlaif 69