JRuby 9000 - Taipei Ruby User's Group 2015

JRuby 9000 - Taipei Ruby User's Group 2015

• 1.
  JRuby 9000 Charles O.Nutter JRuby; Red Hat
• 2.
  JRuby is Ruby… (onthe JVM...shhhh!)
• 3.
  Why the JVMis great for Ruby!
• 4.
  Shoulders of Giants JVMJ.RoseJ. RoseJ. RoseJ. RoseJ. RoseJ. RoseJ. RoseJ. RoseJ. Rose Hiro Marcin Nahi Subbu Douglas Christian Dmitry Tom Charlie JRuby
• 5.
  All the stuff! JVMJ.RoseJ. RoseJ. RoseJ. RoseJ. RoseJ. RoseJ. RoseJ. RoseJ. Rose Garbage Collection Native JIT Profiled Optimizations Native Threading Tooling Cross Platform
• 6.
  Can leverage Java Ecosystem 47klibraries in Maven Hadoop EHCache Selenium Sitemesh Lucene Neo4j JMonkeyEngine
• 7.
  Polyglot Clojure Scala Groovy Jython Rhino/Nashorn/ DynJS (JavaScript) MicroFocus JVMVisual COBOL Java
• 8.
  red/black tree, pureRuby versus native ruby-2.0.0 + Ruby ruby-2.0.0 + C ext jruby + Ruby Runtime per iteration 0 0.75 1.5 2.25 3 0.29s 0.51s 2.48s
• 9.
  GC
• 10.
  GC Matters • Applicationsgrow over time • Ruby is very object-heavy • Multiprocess multiplies the problem • You will eventually have issues
• 11.
  gc_demo.rb • Heavy GC,mix of old and young • Steadily growing heap use
• 12.
  class Simple   attr_accessor :next end top= Simple.new puts Benchmark.measure {   outer = 10   total = 100000   per = 100   outer.times do     total.times do       per.times { Simple.new }       s = Simple.new       top.next = s       top = s     end   end }
• 13.
  0 750 1500 2250 3000 GC count Ruby 2.1.1JRuby
• 14.
  1 10 100 1000 10000 GC count Ruby 2.1.1JRuby
• 15.
  0s 0.45s 0.9s 1.35s 1.8s GC time % Ruby2.2.2 JRuby
• 16.
  Threads
• 17.
  Real Parallellism • Rubythread = JVM thread = native thread • One process can use all cores • One server can handle all requests
• 18.
  Ruby 2.2 unthreaded Ruby 2.2 threaded JRuby unthreaded JRuby threaded
• 19.
  Per-iteration time versusthread count 0.2s 0.35s 0.5s 0.65s 0.8s one thread two threads three threads four threads threaded_reverse
• 20.
  Tools
• 21.
  Profiling • Java profilers •VisualVM,YourKit, NetBeans, JXInsight • jruby [--profile | --profile.graph] • JVM command-line profilers
• 22.
  VisualVM • CPU, memory,thread monitoring • CPU and memory profiling • VisualGC • Heap analysis
• 26.
  Scripting Java
• 27.
  Purugin • Nearly 100%Ruby wrapper • Thin shim makes Java feel very Ruby-like • It’s Minecraft!
• 28.
  Egg Madness
• 29.
  Egg Madness class EggMadnessPlugin includePurugin::Plugin description 'EggMadness', 0.1 def on_enable event(:player_egg_throw) do |e| e.hatching = true e.num_hatches = 50 e.hatching_type = :chicken end end end
• 30.
  1.7.23 JRuby Roadmap mastermaster 1.7.3 1.7.41.7.5 1.7.6 ... 1.7.7 1.7.22 ... 9.0.4 2.2 1.8, 1.9 jruby-1_7jruby-1_7jruby-1_7 master 2.2 1.8, 1.9 End of week Last Friday
• 31.
  JRuby 9000 • Ruby2.2 • New runtime (IR) • Major IO and Encodings overhaul
• 32.
  “It’s over 9000!!!!”
• 33.
  Now What?
• 34.
  PERFORMANCE WORK topic of thistalk Now and into not so distant future!
• 35.
  Recent Wins • JITableblocks • define_method performance • Reduced-cost transient exceptions
• 36.
  Block Jitting • JRuby1.7 only jitted methods • Not free-standing procs/lambdas • Not define_method blocks • Easier to do now with 9000's IR • Blocks JIT now in 9.0.4.0
• 37.
  Jitting is Winning Performanceof define_method in loaded file 0k iters/s 750k iters/s 1500k iters/s 2250k iters/s 3000k iters/s MRI JRuby 9.0.1.0 JRuby 9.0.4.0 normal method define_method method ruby -e 'load "bench_define_method.rb"'
• 38.
  define_method Convenient for metaprogramming, butblocks have more overhead than methods. define_method(:add) do |a, b|
 a + b
 end names.each do |name|
 define_method(name) { send :"do_#{name}" }
 end
• 39.
  :-( 0k iters/s 1000k iters/s 2000kiters/s 3000k iters/s 4000k iters/s MRI JRuby 9.0.1.0 def define_method define_method w/ capture
• 40.
  Optimizing define_method • Noncapturing •Treat as method in compiler • Ignore surrounding scope • Capturing (future work) • Lift read-only variables as constant
• 41.
  Getting Better! 0k iters/s 1000kiters/s 2000k iters/s 3000k iters/s 4000k iters/s MRI JRuby 9.0.1.0 JRuby 9.0.4.0 def define_method define_method w/ capture
• 42.
  Reduced-cost Exceptions • Backtracecost isVERY high on JVM • Heavily optimized, lots of work to build • Exceptions frequently ignored • ...or used as flow control (shame!) • If ignored, backtrace is not needed!
• 43.
  Postfix Antipattern foo rescuenil Exception raised StandardError rescued Exception ignored Result is simple expression, so exception is never visible.
• 44.
  csv.rb Converters Converters ={ integer: lambda { |f|
 Integer(f.encode(ConverterEncoding)) rescue f
 },
 float: lambda { |f|
 Float(f.encode(ConverterEncoding)) rescue f
 },
 ... All trivial rescues, no traces needed.
• 45.
  Simple rescue Improvement 0 150000 300000 450000 600000 Iters/second 524,475 10,700
• 46.
  Nearly Two Magnitudes! 1 10 100 1000 10000 100000 1000000 Iters/second 524,475 10,700
• 47.
  New Runtime? • ASTto semantic representation • Traditional Compiler Design • Wanted Architectural longevity

• 48.
  Lexical Analysis Parsing Semantic Analysis Optimization Bytecode Generation Interpret AST IR Instructions CFG DFG... JRuby 1.7.x 9000+ Dalvik Generation ...
• 49.
  def foo(a, b) c= 1 d = a + c end 0 check_arity(2, 0, -1) 1 a = recv_pre_reqd_arg(0) 2 b = recv_pre_reqd_arg(1) 3 %block = recv_closure 4 thread_poll 5 line_num(1) 6 c = 1 7 line_num(2) 8 %v_0 = call(:+, a, [c]) 9 d = copy(%v_0) 10 return(%v_0) Register-based 3 address format IR InstructionsSemantic Analysis
• 50.
  -Xir.passes=LocalOptimizationPass, DeadCodeElimination def foo(a, b) c= 1 d = a + c end 0 check_arity(2, 0, -1) 1 a = recv_pre_reqd_arg(0) 2 b = recv_pre_reqd_arg(1) 3 %block = recv_closure 4 thread_poll 5 line_num(1) 6 c = 1 7 line_num(2) 8 %v_0 = call(:+, a, [c]) 9 d = copy(%v_0) 10 return(%v_0) Optimization
• 51.
  def foo(a, b) c= 1 d = a + c end 0 check_arity(2, 0, -1) 1 a = recv_pre_reqd_arg(0) 4 thread_poll 5 line_num(1) 6 c = 1 7 line_num(2) 8 %v_0 = call(:+, a, [c]) 9 d = copy(%v_0) 10 return(%v_0) 0 check_arity(2, 0, -1) 1 a = recv_pre_reqd_arg(0) 4 thread_poll 5 line_num(1) 6 c = 7 line_num(2) 8 %v_0 = call(:+, a, [ ]) 9 d = copy(%v_0) 10 return(%v_0) 1 0 check_arity(2, 0, -1) 1 a = recv_pre_reqd_arg(0) 4 thread_poll 5 line_num(1) 7 line_num(2) 8 %v_0 = call(:+, a, [1]) 9 d = copy(%v_0) 10 return(%v_0) Optimization -Xir.passes=LocalOptimizationPass, DeadCodeElimination
• 52.
  0 check_arity(2, 0,-1) 1 a = recv_pre_reqd_arg(0) 4 thread_poll 5 line_num(1) 7 line_num(2) 8 %v_0 = call(:+, a, [1]) 9 d = copy(%v_0) 10 return(%v_0) 0 check_arity(2, 0, -1) 1 a = recv_pre_reqd_arg(0) 4 thread_poll 7 line_num(2) 8 %v_0 = call(:+, a, [1]) 9 d = copy(%v_0) 10 return(%v_0) Optimization -Xir.passes=LocalOptimizationPass, DeadCodeElimination
• 53.
  Inlining • 500 poundgorilla of optimizations • shove method/closure back to callsite • eliminate stack frame • eliminate parameter passing/return • eliminate additional allocation Optimization
• 54.
  Today’s Inliner def decrement_one(i) i- 1 end i = 1_000_000 while i > 0 i = decrement_one(i) end def decrement_one(i) i - 1 end i = 1_000_000 while i < 0 if guard_same? self i = i - 1 else i = decrement_one(i) end end
• 55.
  Numeric Specialization • Everything'san object • JVM has only references and primitives • Not compatible in bytecode • Need to optimize numerics as primitive
• 56.
  def looper(n)
 i =0
 while i < n
 do_something(i)
 i += 1
 end
 end Cached object Call with i New Fixnum i + 1 Probably a Fixnum?
• 57.
  def looper(n)
 i =0
 while i < n
 do_something(i)
 i += 1
 end
 end def looper(long n)
 long i = 0
 while i < n
 do_something(i)
 i += 1
 end
 end Specialize n, i to long def looper(n)
 i = 0
 while i < n
 do_something(i)
 i += 1
 end
 end Deopt to object version if n or i + 1 is not Fixnum
• 58.
  JVM Futures • We'regood friends with OpenJDK folks • Working to improve JVM as well • FFI being added at JVM level • AOT compilation for startup perf
• 59.
  FFI in JVM •Project Panama (JEP-191) • Native support for FFI • Code generators for binding • JIT support for calling • API support for userland
• 60.
  User Code JNI call JNIimpl Target Library Java C/native
• 61.
  User Code JNR stub JNIcall JNI impl libffi Target Library Java C/native
• 62.
  User Code Panama Target Library Java C/native JITknows about both sides
• 63.
  JIT Magic callq <getpidaddress> ; - libSystem.B.dylib ;*invokeinterface getpid ; - GetPidJNRExample::benchGetPid@13 (line 26) ; {optimized virtual_call} Direct call from JITed Ruby code
• 64.
  Startup Time • Byfar our greatest challenge • Everything starts cold: parser, interpreter, compiler, core classes, boot logic • Increasing amount of Ruby in JRuby • Aggravates the problem
• 65.
  JRuby Startup C Ruby JRuby Timein seconds (lower is better) 0s 3.5s 7s 10.5s 14s -e 1 gem --list rake -T in Rals app
• 66.
  --dev • Disables JRubyJIT • Sets JVM to reduced optimization mode • 50% reduction in startup time • Much lower peak perf
• 67.
  JRuby --dev C Ruby JRuby JRuby--dev Time in seconds (lower is better) 0s 3.5s 7s 10.5s 14s -e 1 gem --list rake -T in Rals app
• 68.
  AOT • Precompile JVMbytecode to native • Focus on hot code • Save original structure for optimization • Get JRuby running native right away • AOT compile Ruby to native in future
• 69.
  Getting There C Ruby JRuby JRuby--dev Non-opto AOT Opto AOT Time in seconds (lower is better) 0s 3.5s 7s 10.5s 14s rake -T in Rails app
• 70.
  AOT Future • AOTmight be available in Java 9 • Many tweaks we can make to help it • Ideal: all code run at boot runs native • Should get closer to MRI
• 73.
  ThankYou • @headius • @tom_enebo •http://jruby.org