JRuby 10: Ruby 3.3 on the Modern JVM

JRuby is the most widely deploy alternative Ruby in the world. Up through JRuby 9.4, we have maintained compatibility with old JVM versions, focusing on compatibility and support for legacy platforms. With JRuby 10, we're making a huge leap forward, with support for the latest JVM features (native functions and memory, true lightweight fibers, fast startup and warmup) and a complete set of Ruby 3.3 features (including the fiber scheduler, ractors, IO buffers, the prism parser, and more). We're pushing performance beyond anything we've done before. And we need your help to make this journey. Come see how JRuby brings the best of the modern JVM to Ruby, and how you can get involved.

Delivered at RubyKaigi 2024 in Naha, Okinawa

Transcript

1. JRuby 10! Ruby 3.3 on the Modern JVM
2. Who Am I • Charles Oliver Nutter • @headius(@mastodon.social) • headius@headius.com • JRuby developer for 20 years • Seeking new sponsorship for JRuby
4. What is JRuby? • Ruby on the Java Virtual Machine (JVM) • Ruby implementation fi rst, JVM language second • Many bene fi ts from JVM ecosystem • Ruby code should "just work" • Different extension API, no forking, parallel threads • Thousands of production users, 17 years of real-world use
5. JVM Advantage • World class garbage collectors (many choices) • Native JIT (JRuby was the fi rst JIT for Ruby) • Also inlines JRuby extensions, JVM libraries • Monitoring and pro fi ling tools (many choices, most are Free) • Deploy anywhere (no compiling, no C code, many platforms) • Thousands of JVM developers making it better
6. JRuby 9.4 • Stable release, supported until 2026(?) • Ruby 3.1 compatible • Java 8+ compatible • rvm, ruby-install, ruby-build, OS packages, Windows installer, Docker images, tarballs, zips, whatever • Thousands of users, billions of requests worldwide
7. Example Users • Kami: homework app for teachers, students • Millions of PDFs processed by JRuby every day • Datek: point-of-sale, airplane refueling terminals, ad kiosks • Looker: business analytics platform from Google • Kinetic Data: business portal and automation platform • Let us know if you use JRuby!
8. JRuby Compiler Pipeline Ruby (.rb) JIT Java Instructions (java bytecode) Ruby Instructions (IR) parse interpret interpreter interpret C1 compile native code better native code java bytecode interpreter execute C2 compile Java Virtual Machine JRuby Internals
9. Composition of CRuby Ruby parser Compiler and IR Core classes Standard library Native/C Ruby Rust
10. Native/C Ruby Composition of JRuby Ruby parser Compiler and IR Core classes Standard library Java
11. Better Extension Performance 0M 0.3M 0.6M 0.9M 1.2M small medium large 0.13 0.29 1.1 0.06 0.11 0.72 MRI (oj) JRuby (oj) Millions of loads per second (higher is better)
12. Better Scaling requests per second per MB of memory (16-way concurrency) 0rps/mb 0.45rps/mb 0.9rps/mb 1.35rps/mb 1.8rps/mb 1.72 rps/MB 0.92 rps/MB 0.8 rps/MB CRuby CRuby + YJIT JRuby 300MB heap One JRuby process can run your entire site
13. Graphics GUIs and Games Shoes 4 Glimmer Minecraft
14. JRuby on Android ruboto.org
15. JRuby 10
16. JRuby 10! • Major leap forward • Ruby 3.3 3.4 support, Java 17 (or 21) minimum • New Prism parser with complete language features • Targeted optimization across the board • Our biggest jump since JRuby 9000 (9.0.0.0) • Now is the time to contribute! 𝕏
17. Ruby 3.4 Support
18. Ruby 3.4 Compatible • Language specs: 98.6% passing • Core specs: 97% passing • Same default and bundled gems, some with JRuby extensions • Releasing right after CRuby 3.4 • And preview releases maybe?
19. Ruby Parser • Two parsers: Java (port of C version) and Prism (new C-based) • Future is Prism by default • Ship native library for most platforms • Ship WASM build that runs on JVM without native code • Prism already integrated in JRuby 9.4!
20. Optimization
21. Compatibility Before Optimization • Compatibility fi rst • Keep up with Ruby features • Support users and fi x bugs • Now: caught up with CRuby, more compatible than ever • Finally doing long-planned optimizations!
22. Frame-aware Methods • Some methods can read/write the caller frame • __method__/__callee__ need called method's name • block_given? needs passed block • JVM does not let us access frame (security etc) • Put frame on heap, expensive and breaks optimizations • Optimized: pass frame data on stack, special call site
23. __method__ performance 0M iter/s 2.25M iter/s 4.5M iter/s 6.75M iter/s 9M iter/s __method__ 8.4M 4.4M 2.5M CRuby JRuby 9.4 CRuby YJIT JRuby 10
24. ALOAD 0 ALOAD 4 ALOAD 5 ALOAD 2 GETSTATIC org/jruby/runtime/Visibility.PUBLIC : Lorg/jruby/runtime/Visibility; ALOAD 3 INVOKEVIRTUAL org/jruby/runtime/ThreadContext.preMethodFrameOnly (Lorg/jruby/RubyModul ALOAD 0 ALOAD 2 INVOKEDYNAMIC callVariable:__method__(Lorg/jruby/runtime/ThreadContext;Lorg/jruby/runt // handle kind 0x6 : INVOKESTATIC org/jruby/ir/targets/indy/SelfInvokeSite.bootstrap(Ljava/lang/invoke/MethodHandles$L // arguments: 0, 0, "-e", 1 ] Load method name on stack Update frame on heap Normal call to __method__
25. InvokeDynamic • JVM's special sauce for dynamic languages • De fi ne a new "instruction" • Write code to connect call site to instruction logic • JIT optimizes like static JVM bytecode • Most JRuby optimizations use InvokeDynamic
26. ALOAD 0 ALOAD 2 ALOAD 5 INVOKEDYNAMIC callVariable:__method__(Lorg/jruby/runtime/ThreadContext;Lorg/jruby/runt // handle kind 0x6 : INVOKESTATIC org/jruby/ir/targets/indy/FrameNameSite.frameNameBootstrap(Ljava/lang/invoke/MethodH // arguments: "-e", 1 ] Load method name on stack Special call to name-aware instruction FrameNameSite calls frameless __method__ with name or makes normal method call
27. __method__ performance 0M iter/s 2.25M iter/s 4.5M iter/s 6.75M iter/s 9M iter/s __method__ 8.4M 4.4M 2.5M CRuby JRuby 9.4 CRuby YJIT JRuby 10
28. __method__ performance 0M iter/s 10M iter/s 20M iter/s 30M iter/s 40M iter/s __method__ 36.30M 8.40M 4.40M 2.50M CRuby JRuby 9.4 CRuby YJIT JRuby 10
29. block_given? performance 0M iter/s 5M iter/s 10M iter/s 15M iter/s 20M iter/s block_given? 18.9M 6.4M 2.6M CRuby JRuby 9.4 CRuby YJIT JRuby 10
30. block_given? performance 0M iter/s 75M iter/s 150M iter/s 225M iter/s 300M iter/s block_given? 241.5M 18.9M 6.4M 2.6M CRuby JRuby 9.4 CRuby YJIT JRuby 10
31. String Interpolation • Too much bytecode to compile interpolated string • Harder to inline, slower to warm up • Optimized: special call site with static string and pattern • Small bytecode, better optimization
32. "foo#{a}bar#{b}baz#{c}"
33. ALOAD 0 INVOKEDYNAMIC bufferString(Lorg/jruby/runtime/ThreadContext;)Lorg/jruby/RubyStr ALOAD 0 INVOKEDYNAMIC frozen(Lorg/jruby/runtime/ThreadContext;)Lorg/jruby/RubyString; INVOKEVIRTUAL org/jruby/RubyString.cat19 (Lorg/jruby/RubyString;)Lorg/jruby/Rub ALOAD 8 INVOKEVIRTUAL org/jruby/RubyString.appendAsDynamicString (Lorg/jruby/runtime/bu ALOAD 0 INVOKEDYNAMIC frozen(Lorg/jruby/runtime/ThreadContext;)Lorg/jruby/RubyString; INVOKEVIRTUAL org/jruby/RubyString.cat19 (Lorg/jruby/RubyString;)Lorg/jruby/Rub ALOAD 9 INVOKEVIRTUAL org/jruby/RubyString.appendAsDynamicString (Lorg/jruby/runtime/bu ALOAD 0 INVOKEDYNAMIC frozen(Lorg/jruby/runtime/ThreadContext;)Lorg/jruby/RubyString; INVOKEVIRTUAL org/jruby/RubyString.cat19 (Lorg/jruby/RubyString;)Lorg/jruby/Rub ALOAD 10 INVOKEVIRTUAL org/jruby/RubyString.appendAsDynamicString (Lorg/jruby/runtime/bu ASTORE 11
34. 0001 putobject "foo" 0003 getlocal_WC_0 a@0 0005 dup 0006 objtostring <calldata!mid:to_s, argc:0, FCALL|ARGS_SIMPLE> 0008 anytostring 0009 putobject "bar" 0011 getlocal_WC_0 b@1 0013 dup 0014 objtostring <calldata!mid:to_s, argc:0, FCALL|ARGS_SIMPLE> 0016 anytostring 0017 putobject "baz" 0019 getlocal_WC_0 c@2 0021 dup 0022 objtostring <calldata!mid:to_s, argc:0, FCALL|ARGS_SIMPLE> 0024 anytostring 0025 concatstrings 6
35. ALOAD 0 INVOKEDYNAMIC bufferString(Lorg/jruby/runtime/ThreadContext;)Lorg/jruby/RubyStr ALOAD 0 INVOKEDYNAMIC frozen(Lorg/jruby/runtime/ThreadContext;)Lorg/jruby/RubyString; INVOKEVIRTUAL org/jruby/RubyString.cat19 (Lorg/jruby/RubyString;)Lorg/jruby/Rub ALOAD 8 INVOKEVIRTUAL org/jruby/RubyString.appendAsDynamicString (Lorg/jruby/runtime/bu ALOAD 0 INVOKEDYNAMIC frozen(Lorg/jruby/runtime/ThreadContext;)Lorg/jruby/RubyString; INVOKEVIRTUAL org/jruby/RubyString.cat19 (Lorg/jruby/RubyString;)Lorg/jruby/Rub ALOAD 9 INVOKEVIRTUAL org/jruby/RubyString.appendAsDynamicString (Lorg/jruby/runtime/bu ALOAD 0 INVOKEDYNAMIC frozen(Lorg/jruby/runtime/ThreadContext;)Lorg/jruby/RubyString; INVOKEVIRTUAL org/jruby/RubyString.cat19 (Lorg/jruby/RubyString;)Lorg/jruby/Rub ALOAD 10 INVOKEVIRTUAL org/jruby/RubyString.appendAsDynamicString (Lorg/jruby/runtime/bu ASTORE 11
36. ALOAD 0 ALOAD 8 ALOAD 9 ALOAD 10 INVOKEDYNAMIC buildDynamicString(Lorg/jruby/runtime // handle kind 0x6 : INVOKESTATIC org/jruby/ir/targets/indy/BuildDynamicStringSite. // arguments: "foo", "UTF-8",
37. BuildDynamicString • Allocate large enough buffer for all elements • Pro fi le to pick "right size"? • Static strings copy directly into buffer • "Appendable" objects copy directly into buffer • Only non-String objects create temporary strings
38. 0 7.5 15 22.5 30 "#{n}" "foo#{n}" "#{n}bar" "#{n}#{n}" "foo#{n}bar" "#{n}bar#{n}" "#{n}#{n}bar" "foo#{n}#{n}" "#{n}#{n}#{n}" "foo#{n}bar#{n}baz" "foo#{n}bar#{n}baz#{n}" "#{x}#{x}#{x}#{x}#{x}" "#{x}#{x}#{x}#{x}#{x}#{x}#{x}#{x}#{x}#{x}" CRuby 3.4 YJIT JRuby 10
39. Many Opportunities • Special variables like $~ and $_ • Read-only closure variables passed on stack • Block-receiving methods inlined with block • Smarter object shapes for instance variables, strings, arrays • Inline super calls, metaprogramming, and many others • JRuby 10 will be faster and warm up more quickly!
40. Modern JVM
41. Better Fibers
42. Fibers with Project Loom • Thread-based fi bers don't scale • Enumerators use fi bers • Structured concurrency is coming • Loom brings fi bers to JVM • Easily handles thousands of fi bers • Faster context-switching
43. Faster FFI
44. FFI With Project Panama • Foreign function interface (FFI) • With JVM help to make direct calls • Foreign memory API • JVM-assisted access, lifecycle • Make FFI calls as fast as C ext • Time to get rid of C extensions!
45. Faster Startup and Warmup
46. JRuby Compiler Pipeline Ruby (.rb) JIT Java Instructions (java bytecode) Ruby Instructions (IR) parse interpret interpreter interpret C1 compile native code better native code java bytecode interpreter execute C2 compile Java Virtual Machine JRuby Internals
47. Startup Time • Very hard for JRuby, due to JVM design • Project CRaC: checkpoint a running JVM and restore it • Warm up JRuby and start running immediately! • Linux and Docker for now, more platforms later • Project Leyden: ahead-of-time compile for OpenJDK • JVM JIT server: start with JIT code from previous run
48. ruby -e 1 0s 0.45s 0.9s 1.35s 1.8s -e 1 0.21s 1.271s 1.686s 0.053s CRuby 3.2 JRuby 9.4 JRuby 9.4 --dev JRuby 9.4 CRaC
49. rails new testapp --skip-bundle 0s 1.5s 3s 4.5s 6s rails new testapp --skip-bundle 0.89s 2.7s 5.918s 0.314s CRuby JRuby JRuby --dev JRuby CRaC
50. Future of JRuby
51. JRuby Future • JRuby 9.4 continues to stabilize, moving to maintenance mode • JRuby 10 this year bringing 3.4, faster execution, new JVM stuff • Big announcement for the fi rst time today...
52. A New Path for JRuby! • JRuby's time at Red Hat is coming to an end • We are grateful for 12 years of funding • Nothing to do with JRuby, just new priorities at Red Hat • We want to keep working on JRuby for you! • Seeking sponsors, patrons to keep project going • Commercial support offering coming soon!
53. JRuby Support! • Working on a support company for JRuby • Various tiers from "supporter" to "enterprise" levels • Prioritized bug fi xes, optimizations • Help with pro fi ling, deployment, and more • Please contact us at support@jruby.org for more information!
54. Thank You! • Charles Oliver Nutter • headius@headius.com • @headius(@mastodon.social) • Please email support@jruby.org! • https://github.com/jruby/jruby • https://www.jruby.org • JRuby room on [matrix]