This document summarizes Rubinius, an implementation of the Ruby programming language that includes a bytecode virtual machine written in C++ and Ruby. Some key points: - Rubinius compiles Ruby code to bytecode that runs on its built-in virtual machine. This provides performance improvements over interpreting Ruby code. - The virtual machine is implemented in both C++ and Ruby to provide flexibility. It can inline methods, perform just-in-time compilation, and garbage collect memory. - Rubinius aims to be a complete Ruby implementation while also improving performance through techniques like inline caching, profiling, and garbage collection optimizations.

1. Rubinius
Use Ruby

2. Dirkjan Bussink
d.bussink@gmail.com

4. 2008

5. Dynamic
vs.
Static

6. x = 10
x = 'a'
int x = 10
string x = 'a' => ERROR

7. Strong
vs.
Weak

8. x = 10
y = "20"
x + y
# Javascript
=> 1020
# PHP
=> 30

9. Ruby

10. puts "Hello world!"

11. class MyAwesomeObject
def initialize
puts "Running constructor"
end
def cool_method(arg1, arg2)
arg1 + arg2
end
end

12. [1, 2, 3, 4].each do |e|
puts e
end

13. module Person
def name
puts "Every person has name"
end
end
class Student
include Person
end
Student.new.name

14. Rubinius

15. Virtual Machine

16. Kernel

17. 2006
Evan Phoenix
Brian Ford

18. Virtual Machine

19. C++

20. Ruby

21. 0000: meta_push_0
0001: set_local 0 # i
0003: pop
0004: push_local 0 # i
0006: push_literal 1000
0008: meta_send_op_lt :<
0010: goto_if_false 23
i = 0
0012: push_local 0 # i
while i < 1000 do 0014: meta_push_1
i = i + 1 0015: meta_send_op_plus :+
0017: set_local 0 # i
end 0019: pop
0020: check_interrupts
0021: goto 4
0023: push_nil
0024: pop
0025: push_true
0026: ret

22. Fancy
class Person {
read_write_slots: ['name, 'age, 'city]
def initialize: @name age: @age city: @city {
}
def go_to: city {
if: (city is_a?: City) then: {
@city = city
}
}
def to_s {
"Person: #{@name}, #{@age} years old, living in #{@city}"
}
}

24. JavaScript

25. JavaScript
Python

26. JavaScript
Python
Brainfuck

28. Ruby in Ruby

29. def each
return to_enum(:each) unless block_given?
i = @start
total = i + @total
tuple = @tuple
while i < total
yield tuple.at(i)
i += 1
end
self
end

30. Ruby for Rubyists

31. Improve
everything

32. Compiler

33. class FixnumLiteral < NumberLiteral
def initialize(line, value)
@line = line
@value = value
end
def bytecode(g)
pos(g)
g.push @value
end
def defined(g)
g.push_literal "expression"
end
end

34. Ruby is slow!

35. Flexibility

36. class Array
def sum
inject(0) {|total, e| total + e.to_i}
end
end

37. class Bignum
def +(other)
self - other
end
end

38. "The edges of the sword are life and death,
no one knows which is which"
Ikkyu Sojun, 15th Century Zen master

39. Hard, but not
impossible

40. Inline caching

41. p = Person.new
...
p.name

43. class Person
def name
"me"
end
end

44. module Named
def name
class Person
"named"
def name
end
"me"
end
end
class Person
end
include Named
end

45. module Named
def name class Person
class Person
"named" end
def name
end
"me"
end def p.name
end
class Person "specific"
end
include Named end
end

46. class Person
attr_accessor :name
end
10000.times do
p = Person.new
p.name
end

47. There are only two hard
problems in Computer Science:
cache invalidation,
naming things
and off-by-one errors

49. module Naming
def name
"me2"
end
end
class Person
include Naming
end
10000.times do
p = Person.new
p.name
end

50. module Naming
def name
"me2" class Person
end def name
end "new_name"
end
class Person end
include Naming
end 10000.times do
p = Person.new
10000.times do p.name
p = Person.new end
p.name
end

51. p = OtherObject.new
...
p.name

52. JIT

53. “...we finally managed to get our Linux (...) builds to use
GCC 4.5, ... and profile guided optimization enabled”
Mike Hommey - on Firefox 6 performance

54. def method1
1 + 1
end
def method2
2 + 1
end
10000.times do
method1
end

55. members of rubinius::VMMethod:
total_args = 0,
call_count = 21,
llvm_function_ = 0x0,
name_ = 0x6306,

56. static const int default_jit_call_til_compile = 4000;

57. pushl %ebp
movl %esp, %ebp
subl $4, %esp
movl $10, -4(%ebp)
leal -4(%ebp), %eax
addl $66, (%eax)
leave
ret

59. #include <stdio.h>
int func() {
int i = 0;
i += 10;
return i;
}

60. ; ModuleID = '<stdin>'
target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-
i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-
v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64"
target triple = "x86_64-apple-darwin10.7"
define i32 @func() nounwind ssp {
entry:
%retval = alloca i32
%0 = alloca i32
%i = alloca i32
%"alloca point" = bitcast i32 0 to i32
store i32 0, i32* %i, align 4
%1 = load i32* %i, align 4
%2 = add nsw i32 %1, 10
store i32 %2, i32* %i, align 4
%3 = load i32* %i, align 4
store i32 %3, i32* %0, align 4
%4 = load i32* %0, align 4
store i32 %4, i32* %retval, align 4
br label %return
return: ; preds =
%entry
%retval1 = load i32* %retval
ret i32 %retval1
}

61. ; ModuleID = '<stdin>'
target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-
i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-
v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-
n8:16:32:64"
target triple = "x86_64-apple-darwin10.7"
define i32 @func() nounwind readnone ssp {
entry:
ret i32 10
}

62. Go JIT!
RBX LLVM
thread(s) thread
Here it is!

63. members of rubinius::VMMethod:
total_args = 0,
call_count = 21,
llvm_function_ = 0x102c07b30,
name_ = 0x6306,

64. Code inlining

65. array = [1] * 1000000
array.each do |element|
puts "element: #{element}"
end

67. def method1
1 + 1
end
def method2
method1
end
100.times do
method2
end

68. def method1 def method1
1 + 1 1 + 1
end end
def method2 def method2
method1 method1
end end
100.times do 100.times do
method2 method1
end end

69. def method1 def method1
1 + 1 1 + 1
end end
def method2 def method2
method1 method1
end end
100.times do 100.times do
method2 method1
end end

70. def method1 def method1 def method1
1 + 1 1 + 1 1 + 1
end end end
def method2 def method2 def method2
method1 method1 method1
end end end
100.times do 100.times do 100.times do
method2 method1 1 + 1
end end end

71. def method1 def method1 def method1
1 + 1 1 + 1 1 + 1
end end end
def method2 def method2 def method2
method1 method1 method1
end end end
100.times do 100.times do 100.times do
method2 method1 1 + 1
end end end

73. def awesome(x)
return 0 if x == 0
x + 1
end
def use_awesomeness_regular
a = awesome(0)
b = awesome(1)
a + b
end

74. def use_awesomeness_inlined
a = begin
return 0 if 0 == 0
0 + 1
end
b = begin
return 1 if 1 == 0
1 + 1
end
a + b
end

76. array = [1] * 1000000
array.each do |element|
puts "element: #{element}"
end

77. array = [1] * 1000000
array = [1] * 1000000
i = 0
size = array.size
array.each do |element|
while i < size
puts "element: #{element}"
puts "element: #{array[i]}"
end
i += 1
end

78. array = [1] * 1000000
array = [1] * 1000000
i = 0
array.each do |element|
puts "element: #{element}"
== size = array.size
while i < size
puts "element: #{array[i]}"
end
i += 1
end

80. array = [1] * 100
array.each do |element|
puts "element: #{element}"
b = 2
end
puts b

81. array = [1] * 100
array = [1] * 100
i = 0
size = array.size
array.each do |element|
while i < size
puts "element: #{element}"
puts "element: #{array[i]}"
b = 2
b = 2
end
i += 1
end
puts b
puts b

82. array = [1] * 100
array = [1] * 100
i = 0
size = array.size
array.each do |element|
while i < size
puts "element: #{element}"
b = 2 != puts "element: #{array[i]}"
b = 2
end
i += 1
end
puts b
puts b

84. Control flow issues

85. Control flow issues
Scoping issues

86. Control flow issues
Scoping issues
Too big piece of code

87. Garbage
Collection

89. Mark
Sweep

91. Generational
Garbage
Collection

92. Young
Mature
Large

93. Young
Semi Space
collector

108. Mature
Immix

113. Large
Mark - sweep

114. Creating less
garbage

115. class Address
attr_reader :street
attr_reader :number
attr_reader :city
end

116. class Address
attr_reader :street
attr_reader :number
attr_reader :city
end
Address.instance_variable_get("@seen_ivars")
=> [:@street, :@number, :@city]

117. a = Address.new
a.street = "Street"
a.number = "1"
a.city = "Enschede"
Rubinius.memory_size(a) => 56
VS
Rubinius.memory_size(a) => 160

118. What else?

119. http://rubini.us/
https://github.com/evanphx/rubinius

120. 1 patch == commit access

121. Questions?